University of Groningen
Living with chronic headache
Ciere, Yvette
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Ciere, Y. (2018). Living with chronic headache: A personal goal and self-regulation perspective. University of Groningen.
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Momentary pain intensity, negative affect, and
energy predict daily activity interference in
chronic migraine: a prospective
smartphone-based diary study
Yvette Ciere, Evelien Snippe, Mariëlle Padberg, Bram Jacobs,
Annemieke Visser, Robbert Sanderman, Joke Fleer
Revision
Chapter
ABSTRACT
Background: In addition to head pain, negative affect (e.g., sadness, frustration) and a lack
of energy are symptoms that may interfere with daily functioning in chronic migraine. The aim of this study was to examine the independent and additive effects of momentary pain intensity, negative affect, and energy on the interference of daily activities in chronic migraine. We further examined the moment-to-moment interaction between these symptoms.
Methods: 61 adults with chronic migraine completed smartphone-based assessments of
symptoms and activity interference at 9 semi-random moments per day, during 7 consecutive days. Data were analysed using time-lagged multilevel models.
Result: Pain intensity (.19, p < .01), negative affect (.23, p < .01), and energy (-.15, p < .01)
were associated with next-moment activity interference. Activity interference was not greater when symptoms co-occurred. Symptoms were significantly interrelated; largest effects were found for the time-lagged association between negative affect and energy (-.17, p < .01), negative affect and pain intensity (.11, p < .01), and pain intensity and energy (-.14, p < .01).
Discussion: This is the first study to provide insight into the moment-to-moment associations
between symptoms and activity interference in chronic migraine. Results suggest that, in addition to pain intensity, negative affect may be an important target for interventions aimed at improving daily functioning in chronic migraine.
Activity interference in chronic migraine _________________________________________________________________________
INTRODUCTION
Not only frequent episodes of intense pain, but also concomitant symptoms may interfere with daily functioning in chronic migraine (CM) (Raggi et al., 2012). Negative affect (e.g., sadness, frustration) and a lack of energy are particularly common symptoms and could occur both during a migraine attack, as well as in between attacks (Buse, Rupnow, & Lipton, 2009; Dahlof & Solomon, 1998). Individuals with frequent migraine have been found to report higher negative affect as compared to individuals with less frequent or no migraine (Louter et al., 2015). Between 13 and 42% of CM patients meet criteria for a mood disorder (Buse, Silberstein, Manack, Papapetropoulos, & Lipton, 2013). Elevated fatigue, which is closely related to low energy, has been reported by as many as 84% of individuals with CM (Peres, Zukerman, Young, & Silberstein, 2002). Pain, negative affect, and low energy may independently and interactively interfere with the engagement in daily activities, such as work, school, or household activities. As such activities are vital for a sense of purpose and meaning in life, their interference may have negative implications for well-being (Emmons, 1999; Little & Chambers, 2004). This study aimed to gain insight into the daily dynamics among pain intensity, negative affect, energy, and their association with activity interference in chronic migraine
Previous evidence in headache and other chronic conditions suggests that pain intensity, negative affect, and a lack of energy may each interfere with the engagement in daily activities.(Buse et al., 2012; Holroyd, Drew, Cottrell, Romanek, & Heh, 2007; Oncu, Basoglu, & Kuran, 2013; Pittion-Vouyovitch et al., 2006; Romberg-Camps et al., 2010; van de Port, Kwakkel, Schepers, Heinemans, & Lindeman, 2007).Alarge population-based study in chronic migraine for instance found that higher pain intensity was related to greater perceived interference of usual daily activities such as work, school and social
activities.(Buse et al., 2012) Similarly, another study found that episodic and chronic migraine patients with higher pain intensity reported greater emotional and functional disability (Magnusson & Becker, 2003b). Furthermore, in a study in frequent migraine, the diagnosis of a mood disorder predicted a greater impact of migraine on daily living
(Holroyd et al., 2007). The association between energy and activity interference has thus far not been studied in chronic migraine, nor in any other headache type. However, fatigue has been associated with poorer perceived daily functioning in other chronic somatic conditions (Oncu et al., 2013; Pittion-Vouyovitch et al., 2006; Romberg-Camps et al., 2010; van de Port et al., 2007).
Importantly, pain intensity, negative affect, and energy may interact in their influence on daily activities. At least two interactive processes are plausible. First, studies in other chronic conditions have shown that pain, negative affect, and fatigue often co-occur (Fox & Lyon, 2006; Motl & McAuley, 2010). When symptoms co-occur, their effect on the perceived interference of daily activities could be additive (Lenz, Pugh, Milligan, Gift, & Suppe, 1997). Second, pain, negative affect, and energy may be interrelated. For instance,
ABSTRACT
Background: In addition to head pain, negative affect (e.g., sadness, frustration) and a lack
of energy are symptoms that may interfere with daily functioning in chronic migraine. The aim of this study was to examine the independent and additive effects of momentary pain intensity, negative affect, and energy on the interference of daily activities in chronic migraine. We further examined the moment-to-moment interaction between these symptoms.
Methods: 61 adults with chronic migraine completed smartphone-based assessments of
symptoms and activity interference at 9 semi-random moments per day, during 7 consecutive days. Data were analysed using time-lagged multilevel models.
Result: Pain intensity (.19, p < .01), negative affect (.23, p < .01), and energy (-.15, p < .01)
were associated with next-moment activity interference. Activity interference was not greater when symptoms co-occurred. Symptoms were significantly interrelated; largest effects were found for the time-lagged association between negative affect and energy (-.17, p < .01), negative affect and pain intensity (.11, p < .01), and pain intensity and energy (-.14, p < .01).
Discussion: This is the first study to provide insight into the moment-to-moment associations
between symptoms and activity interference in chronic migraine. Results suggest that, in addition to pain intensity, negative affect may be an important target for interventions aimed at improving daily functioning in chronic migraine.
Activity interference in chronic migraine _________________________________________________________________________
INTRODUCTION
Not only frequent episodes of intense pain, but also concomitant symptoms may interfere with daily functioning in chronic migraine (CM) (Raggi et al., 2012). Negative affect (e.g., sadness, frustration) and a lack of energy are particularly common symptoms and could occur both during a migraine attack, as well as in between attacks (Buse, Rupnow, & Lipton, 2009; Dahlof & Solomon, 1998). Individuals with frequent migraine have been found to report higher negative affect as compared to individuals with less frequent or no migraine (Louter et al., 2015). Between 13 and 42% of CM patients meet criteria for a mood disorder (Buse, Silberstein, Manack, Papapetropoulos, & Lipton, 2013). Elevated fatigue, which is closely related to low energy, has been reported by as many as 84% of individuals with CM (Peres, Zukerman, Young, & Silberstein, 2002). Pain, negative affect, and low energy may independently and interactively interfere with the engagement in daily activities, such as work, school, or household activities. As such activities are vital for a sense of purpose and meaning in life, their interference may have negative implications for well-being (Emmons, 1999; Little & Chambers, 2004). This study aimed to gain insight into the daily dynamics among pain intensity, negative affect, energy, and their association with activity interference in chronic migraine
Previous evidence in headache and other chronic conditions suggests that pain intensity, negative affect, and a lack of energy may each interfere with the engagement in daily activities.(Buse et al., 2012; Holroyd, Drew, Cottrell, Romanek, & Heh, 2007; Oncu, Basoglu, & Kuran, 2013; Pittion-Vouyovitch et al., 2006; Romberg-Camps et al., 2010; van de Port, Kwakkel, Schepers, Heinemans, & Lindeman, 2007).Alarge population-based study in chronic migraine for instance found that higher pain intensity was related to greater perceived interference of usual daily activities such as work, school and social
activities.(Buse et al., 2012) Similarly, another study found that episodic and chronic migraine patients with higher pain intensity reported greater emotional and functional disability (Magnusson & Becker, 2003b). Furthermore, in a study in frequent migraine, the diagnosis of a mood disorder predicted a greater impact of migraine on daily living
(Holroyd et al., 2007). The association between energy and activity interference has thus far not been studied in chronic migraine, nor in any other headache type. However, fatigue has been associated with poorer perceived daily functioning in other chronic somatic conditions (Oncu et al., 2013; Pittion-Vouyovitch et al., 2006; Romberg-Camps et al., 2010; van de Port et al., 2007).
Importantly, pain intensity, negative affect, and energy may interact in their influence on daily activities. At least two interactive processes are plausible. First, studies in other chronic conditions have shown that pain, negative affect, and fatigue often co-occur (Fox & Lyon, 2006; Motl & McAuley, 2010). When symptoms co-occur, their effect on the perceived interference of daily activities could be additive (Lenz, Pugh, Milligan, Gift, & Suppe, 1997). Second, pain, negative affect, and energy may be interrelated. For instance,
Activity interference in chronic migraine
_________________________________________________________________________ greater pain intensity has been found to be associated with higher negative affect
(Magnusson & Becker, 2003a). If pain, negative affect, and energy indeed mutually influence each other, this may be even more aversive for the ability to engage in daily life activities. If one of these symptoms is triggered, this may set a downward spiral in motion by both directly and indirectly impacting engagement in activities.
Nevertheless, previous studies in CM have typically used retrospective methods (e.g., questionnaires) to assess symptoms and daily functioning. Such methods involve participant recall of average experience over a given period of time (e.g., average interference in the past week). In addition to being susceptible to recall bias (Schwarz, 2007), retrospective methods do not allow investigation of the associations that may take place within the day, or their temporal order. As a result, there is limited insight into the daily dynamics among pain, negative affect and energy, and their effect on daily functioning in chronic migraine. Yet, such evidence is needed to determine which symptoms are the starting point of the temporal flow of changes. These symptoms may be the most promising targets for intervention in order to improve daily functioning. For example, if low energy precedes increases in pain intensity and negative affect, managing low levels of energy may be an important target for intervention.
The Experience Sampling Method (ESM) (Csikszentmihalyi & Larson, 1987; de Vries, 1992) is a method that enables the examination of within-subject variability and temporal precedence, because of the repeated and frequent measures of experiences over the flow of everyday life (e.g., by using a diary) (Myin-Germeys et al., 2009). This study employed the ESM to study the within-day, temporal associations between pain intensity, negative affect, energy, and activity interference in chronic migraine. First, we examined the independent and additive effects of pain, affect and energy on activity interference. We hypothesized that higher pain intensity, higher negative affect, and lower energy would be independently associated with higher next-moment activity interference. Furthermore, the co-occurrence of symptoms was expected to contribute to greater activity interference. Second, we explored the temporal associations among pain intensity, negative affect, and energy to explore whether they all reinforce each other, or whether one of these symptoms is a more important predictor of the other symptoms.
METHODS Participants
Adults with chronic migraine were recruited between September 2015 and June 2016. Patients were informed on the study via information letters sent by two neurology outpatient clinics, via advertisements posted by the Dutch Society for Headache Patients, and through advertisements in local newspaper. Patients could indicate their interest in the study by directly contacting the research team or filling out a contact form. Patients were
Activity interference in chronic migraine _________________________________________________________________________ called by the researcher (YC) for further information. Those who were still interested after receiving additional information, were screened for eligibility.
Following ICHD-III criteria for chronic migraine (Headache Classification Committee of the International Headache Society (IHS, 2013), patients were eligible when first onset of headache was longer than a year ago and headache was present on at least 15 days per month in the past 3 months, of which at least 8 days with migraine. Patients were excluded if they reported a secondary headache disorder (e.g., cluster headache; with exception of medication-overuse headache) or when migraine had not been previously diagnosed by a physician.Other exclusion criteria were pregnancy in the past year, acute medication withdrawal in the past 3 months, changes in prophylactic or psychological treatment in the past 2 months, a history of severe mental illness (e.g., psychosis), severe memory deficits, or language difficulties. In addition, patients could not participate when they did not have a smartphone with internet connection or were not willing to use it for the study.
A total number of 159 patients was screened for eligibility, of which 71 were eligible for the study. Of these, 67 patients provided informed consent. Six patients dropped out during the study, resulting in a final sample of 61 participants. Sample characteristics are presented in Table 1. The majority of participants was female, completed middle level or higher education, was in a relationship, and was (self-) employed. Most participants used only acute medication and no preventative medication for their chronic migraines and did not currently receive any additional non-pharmacological treatment.
Activity interference in chronic migraine
_________________________________________________________________________ greater pain intensity has been found to be associated with higher negative affect
(Magnusson & Becker, 2003a). If pain, negative affect, and energy indeed mutually influence each other, this may be even more aversive for the ability to engage in daily life activities. If one of these symptoms is triggered, this may set a downward spiral in motion by both directly and indirectly impacting engagement in activities.
Nevertheless, previous studies in CM have typically used retrospective methods (e.g., questionnaires) to assess symptoms and daily functioning. Such methods involve participant recall of average experience over a given period of time (e.g., average interference in the past week). In addition to being susceptible to recall bias (Schwarz, 2007), retrospective methods do not allow investigation of the associations that may take place within the day, or their temporal order. As a result, there is limited insight into the daily dynamics among pain, negative affect and energy, and their effect on daily functioning in chronic migraine. Yet, such evidence is needed to determine which symptoms are the starting point of the temporal flow of changes. These symptoms may be the most promising targets for intervention in order to improve daily functioning. For example, if low energy precedes increases in pain intensity and negative affect, managing low levels of energy may be an important target for intervention.
The Experience Sampling Method (ESM) (Csikszentmihalyi & Larson, 1987; de Vries, 1992) is a method that enables the examination of within-subject variability and temporal precedence, because of the repeated and frequent measures of experiences over the flow of everyday life (e.g., by using a diary) (Myin-Germeys et al., 2009). This study employed the ESM to study the within-day, temporal associations between pain intensity, negative affect, energy, and activity interference in chronic migraine. First, we examined the independent and additive effects of pain, affect and energy on activity interference. We hypothesized that higher pain intensity, higher negative affect, and lower energy would be independently associated with higher next-moment activity interference. Furthermore, the co-occurrence of symptoms was expected to contribute to greater activity interference. Second, we explored the temporal associations among pain intensity, negative affect, and energy to explore whether they all reinforce each other, or whether one of these symptoms is a more important predictor of the other symptoms.
METHODS Participants
Adults with chronic migraine were recruited between September 2015 and June 2016. Patients were informed on the study via information letters sent by two neurology outpatient clinics, via advertisements posted by the Dutch Society for Headache Patients, and through advertisements in local newspaper. Patients could indicate their interest in the study by directly contacting the research team or filling out a contact form. Patients were
Activity interference in chronic migraine _________________________________________________________________________ called by the researcher (YC) for further information. Those who were still interested after receiving additional information, were screened for eligibility.
Following ICHD-III criteria for chronic migraine (Headache Classification Committee of the International Headache Society (IHS, 2013), patients were eligible when first onset of headache was longer than a year ago and headache was present on at least 15 days per month in the past 3 months, of which at least 8 days with migraine. Patients were excluded if they reported a secondary headache disorder (e.g., cluster headache; with exception of medication-overuse headache) or when migraine had not been previously diagnosed by a physician.Other exclusion criteria were pregnancy in the past year, acute medication withdrawal in the past 3 months, changes in prophylactic or psychological treatment in the past 2 months, a history of severe mental illness (e.g., psychosis), severe memory deficits, or language difficulties. In addition, patients could not participate when they did not have a smartphone with internet connection or were not willing to use it for the study.
A total number of 159 patients was screened for eligibility, of which 71 were eligible for the study. Of these, 67 patients provided informed consent. Six patients dropped out during the study, resulting in a final sample of 61 participants. Sample characteristics are presented in Table 1. The majority of participants was female, completed middle level or higher education, was in a relationship, and was (self-) employed. Most participants used only acute medication and no preventative medication for their chronic migraines and did not currently receive any additional non-pharmacological treatment.
Activity interference in chronic migraine
_________________________________________________________________________
Procedure
ESM diary questionnaires measuring momentary pain intensity, negative affect, energy, and activity interference were administered nine times a day, during seven consecutive days. In addition, an end-of-day diary was used to assess the presence of potential confounding variables during the day (e.g., the occurrence of negative events). Before starting the diary procedure, participants completed a baseline questionnaire including questions about demographic and medical characteristics. The study protocol (NL49506.042) was approved by the medical ethical committees of the participating hospitals. All participants provided written informed consent.
Diary questionnaires were completed via a web-based diary application on the participant’s own smartphone (Sorbi, Mak, Houtveen, Kleiboer, & van Doornen, 2007). Paper-and-pencil diaries were available to use in case of technical problems.ESM diary assessments were scheduled at random moments during the day, within 90-minute time-frames, to obtain a representative sample of moments in a participant’s life. To limit recall bias, questionnaires could be completed up to a maximum of 30 minutes after they were received. Participants were instructed on the procedure in a telephonic briefing session. They were rewarded with €50,- upon completing at least 80% of the diaries.
Measures
Pain intensity – Pain intensity was rated in response to the item: ‘At this moment, I have a headache’. All diary items were answered on a similar 7-point Likert scale, ranging from
0 ‘not at all’ to 6 ‘very much’. Similar items have been used in previous studies involving diary assessment of pain intensity in migraine (Houtveen & Sorbi, 2013; Park, Chu, Kim, Park, & Cho, 2016).
Negative affect – Negative affect was rated in response to the statement ‘At this moment, I feel...’. We selected negative affect items that 1) measured relevant dimensions of affect
(i.e., high and low arousal as well as hedonic and tense arousal), (Matthews, Jones, & Chamberlain, 1990; Watson, Clark, & Tellegen, 1988) and 2) showed sufficient within-person variation over time (as indicated by a Mean Squared Successive Difference (MSSD) higher than 0.80). Selected items included ‘sad’, ‘gloomy’, ‘irritable’, ‘tense’, and
‘worried’. As a factor analysis indicated that these items all loaded onto one factor, a mean score across all items was calculated.
Energy - Energy level was rated in response to the item ‘At this moment, I feel
energetic’. Previous research showed that fatigue could be validly measured using a single
item, which suggests that a single item is also sufficient to assess energy (Van Hooff, Geurts, Kompier, & Taris, 2007).
Activity interference –Activity interference was measured with the item: ‘Since the last beep, I was hindered in my activities’. The experience of pain was not included in this item
Activity interference in chronic migraine _________________________________________________________________________ so that participants could also report a higher score when activities were hindered by other factors than pain (e.g., by fatigue).
Medication use – Since medication use is a contextual variable that may influence the
association between symptoms and activity interference, we included the following item in the ESM diary: ‘Since the last beep, did you use any acute medication for your headache?’. This item was answered with ‘yes’ or ‘no’.
Daily contextual variables - A number of contextual variables that may influence the
association between symptoms and activity interference were assessed once a day at the end of the day. These variables included menstruation (‘yes’ or ‘no’), sleep quality in the previous night (0-6), the severity of negative events during the day (0-6), and whether that day’s headache was perceived as migraine (‘yes’ or ‘no’).
Statistical analyses
The ESM-data had a two-level hierarchical structure (i.e., assessments nested within individuals), data were therefore analyzed with multilevel regression analyses using the XTMIXED command in Stata version 14 (StataCorp, 2015). In all multilevel models, time-varying predictors were first grand-mean centered and then person-mean centered to separate within-subject effects from between-subject effects (Bolger & Laurenceau, 2013). All models included a random intercept for participants. Random slopes for time-varying variables were included when they were larger than zero and when their inclusion improved model fit (as indicated by AIC and BIC). Models with different co-variance structures were compared; the best fitting model was selected based on AIC and BIC criteria.
First, we used univariate models to assess the time-lagged associations between each of the symptoms (i.e., pain, negative affect, energy) and next-moment activity interference as well as the potentially reciprocal time-lagged association between each of the symptoms. In these models, the dependent variable was measured at time ‘t’. Predictors were time in observations, one of the symptoms at ‘t-1’, and the dependent variable at ‘t-1’ to remove autocorrelation. In addition, we controlled for contextual variables that were significantly related (p < .05) to both the dependent variable and the predictor of interest.
Second, we examined the relative effect of each of the symptoms using a multivariate model in which all three symptoms were modelled as predictors of next-moment activity interference. The interactive effect of symptoms was examined by evaluating the significance of the following interaction terms: pain*energy, pain*negative affect, and energy*negative affect. Again, we controlled for the influence of relevant contextual variables.
Activity interference in chronic migraine
_________________________________________________________________________
Procedure
ESM diary questionnaires measuring momentary pain intensity, negative affect, energy, and activity interference were administered nine times a day, during seven consecutive days. In addition, an end-of-day diary was used to assess the presence of potential confounding variables during the day (e.g., the occurrence of negative events). Before starting the diary procedure, participants completed a baseline questionnaire including questions about demographic and medical characteristics. The study protocol (NL49506.042) was approved by the medical ethical committees of the participating hospitals. All participants provided written informed consent.
Diary questionnaires were completed via a web-based diary application on the participant’s own smartphone (Sorbi, Mak, Houtveen, Kleiboer, & van Doornen, 2007). Paper-and-pencil diaries were available to use in case of technical problems.ESM diary assessments were scheduled at random moments during the day, within 90-minute time-frames, to obtain a representative sample of moments in a participant’s life. To limit recall bias, questionnaires could be completed up to a maximum of 30 minutes after they were received. Participants were instructed on the procedure in a telephonic briefing session. They were rewarded with €50,- upon completing at least 80% of the diaries.
Measures
Pain intensity – Pain intensity was rated in response to the item: ‘At this moment, I have a headache’. All diary items were answered on a similar 7-point Likert scale, ranging from
0 ‘not at all’ to 6 ‘very much’. Similar items have been used in previous studies involving diary assessment of pain intensity in migraine (Houtveen & Sorbi, 2013; Park, Chu, Kim, Park, & Cho, 2016).
Negative affect – Negative affect was rated in response to the statement ‘At this moment, I feel...’. We selected negative affect items that 1) measured relevant dimensions of affect
(i.e., high and low arousal as well as hedonic and tense arousal), (Matthews, Jones, & Chamberlain, 1990; Watson, Clark, & Tellegen, 1988) and 2) showed sufficient within-person variation over time (as indicated by a Mean Squared Successive Difference (MSSD) higher than 0.80). Selected items included ‘sad’, ‘gloomy’, ‘irritable’, ‘tense’, and
‘worried’. As a factor analysis indicated that these items all loaded onto one factor, a mean score across all items was calculated.
Energy - Energy level was rated in response to the item ‘At this moment, I feel
energetic’. Previous research showed that fatigue could be validly measured using a single
item, which suggests that a single item is also sufficient to assess energy (Van Hooff, Geurts, Kompier, & Taris, 2007).
Activity interference –Activity interference was measured with the item: ‘Since the last beep, I was hindered in my activities’. The experience of pain was not included in this item
Activity interference in chronic migraine _________________________________________________________________________ so that participants could also report a higher score when activities were hindered by other factors than pain (e.g., by fatigue).
Medication use – Since medication use is a contextual variable that may influence the
association between symptoms and activity interference, we included the following item in the ESM diary: ‘Since the last beep, did you use any acute medication for your headache?’. This item was answered with ‘yes’ or ‘no’.
Daily contextual variables - A number of contextual variables that may influence the
association between symptoms and activity interference were assessed once a day at the end of the day. These variables included menstruation (‘yes’ or ‘no’), sleep quality in the previous night (0-6), the severity of negative events during the day (0-6), and whether that day’s headache was perceived as migraine (‘yes’ or ‘no’).
Statistical analyses
The ESM-data had a two-level hierarchical structure (i.e., assessments nested within individuals), data were therefore analyzed with multilevel regression analyses using the XTMIXED command in Stata version 14 (StataCorp, 2015). In all multilevel models, time-varying predictors were first grand-mean centered and then person-mean centered to separate within-subject effects from between-subject effects (Bolger & Laurenceau, 2013). All models included a random intercept for participants. Random slopes for time-varying variables were included when they were larger than zero and when their inclusion improved model fit (as indicated by AIC and BIC). Models with different co-variance structures were compared; the best fitting model was selected based on AIC and BIC criteria.
First, we used univariate models to assess the time-lagged associations between each of the symptoms (i.e., pain, negative affect, energy) and next-moment activity interference as well as the potentially reciprocal time-lagged association between each of the symptoms. In these models, the dependent variable was measured at time ‘t’. Predictors were time in observations, one of the symptoms at ‘t-1’, and the dependent variable at ‘t-1’ to remove autocorrelation. In addition, we controlled for contextual variables that were significantly related (p < .05) to both the dependent variable and the predictor of interest.
Second, we examined the relative effect of each of the symptoms using a multivariate model in which all three symptoms were modelled as predictors of next-moment activity interference. The interactive effect of symptoms was examined by evaluating the significance of the following interaction terms: pain*energy, pain*negative affect, and energy*negative affect. Again, we controlled for the influence of relevant contextual variables.
Activity interference in chronic migraine
_________________________________________________________________________
RESULTS
Descriptive statistics
A total of 3349 ESM observations was collected. Participants completed on average 89% of the ESM measures (range = 37% - 100%). Table 2 presents the means and variability of the ESM measures. Average scores on all measures were relatively low, in particular for negative affect. As demonstrated by the within-person standard deviations and Mean Squared Successive Differences (MSSD), there was considerable variation in the ESM measures over time (see Table 2).
Table 2 – Means and SDs of ESM measures
MSSD: Mean Squared Successive Difference
Independent and additive effects of symptoms on activity interference
As shown by Figure 1, higher pain intensity, higher negative affect, and lower energy were significantly associated with higher next-moment activity interference. Each unit increase in pain intensity, negative affect, and energy was associated with respectively a .19 and .23 increase, and a .15 decrease, in activity interference on a scale of 0 to 6. In a multivariate model (see Table 3), pain intensity, negative affect, and energy each had an independent effect on next-moment activity interference. Pain intensity was the strongest predictor of next-moment activity interference, followed by negative affect and energy.
Neither the interaction effect between pain intensity and negative affect (.02, SE = .02, p = .18), pain intensity and energy (-.02, SE = .01, p = .07), nor the interaction effect between negative affect and energy (- .01, SE = .02, p = .51) was significant (not shown in a table). This suggests that, contrary to expectations, next-moment activity interference was not greater when symptoms co-occurred.
Activity interference in chronic migraine _________________________________________________________________________
Figure 1 – Time-lagged (univariate) associations between pain intensity, negative affect,
energy, and activity interference, controlled for medication use, sleep quality, and negative event severity.
Associations among symptoms
Pain intensity, negative affect, and energy were found to be significantly interrelated (see Figure 1). The largest effects were found for the associations between negative affect and moment energy, pain intensity and moment energy, and negative affect and next-moment pain intensity. Thus, it appears that these symptoms reinforce each other and, in turn, may interfere with daily activities.
Activity interference in chronic migraine
_________________________________________________________________________
RESULTS
Descriptive statistics
A total of 3349 ESM observations was collected. Participants completed on average 89% of the ESM measures (range = 37% - 100%). Table 2 presents the means and variability of the ESM measures. Average scores on all measures were relatively low, in particular for negative affect. As demonstrated by the within-person standard deviations and Mean Squared Successive Differences (MSSD), there was considerable variation in the ESM measures over time (see Table 2).
Table 2 – Means and SDs of ESM measures
MSSD: Mean Squared Successive Difference
Independent and additive effects of symptoms on activity interference
As shown by Figure 1, higher pain intensity, higher negative affect, and lower energy were significantly associated with higher next-moment activity interference. Each unit increase in pain intensity, negative affect, and energy was associated with respectively a .19 and .23 increase, and a .15 decrease, in activity interference on a scale of 0 to 6. In a multivariate model (see Table 3), pain intensity, negative affect, and energy each had an independent effect on next-moment activity interference. Pain intensity was the strongest predictor of next-moment activity interference, followed by negative affect and energy.
Neither the interaction effect between pain intensity and negative affect (.02, SE = .02, p = .18), pain intensity and energy (-.02, SE = .01, p = .07), nor the interaction effect between negative affect and energy (- .01, SE = .02, p = .51) was significant (not shown in a table). This suggests that, contrary to expectations, next-moment activity interference was not greater when symptoms co-occurred.
Activity interference in chronic migraine _________________________________________________________________________
Figure 1 – Time-lagged (univariate) associations between pain intensity, negative affect,
energy, and activity interference, controlled for medication use, sleep quality, and negative event severity.
Associations among symptoms
Pain intensity, negative affect, and energy were found to be significantly interrelated (see Figure 1). The largest effects were found for the associations between negative affect and moment energy, pain intensity and moment energy, and negative affect and next-moment pain intensity. Thus, it appears that these symptoms reinforce each other and, in turn, may interfere with daily activities.
Activity interference in chronic migraine
_________________________________________________________________________
Between subject variation in within-subject effects
To gain insight into heterogeneity of the estimated effects, best linear unbiased prediction (BLUP) was used to predict deviation from the fixed effects for each individual. Histograms of these predictions showed that the individual deviation from the fixed effects was not normally distributed. That is, for most coefficients, there appeared to be a subgroup of patients who demonstrated much smaller or larger effects than the estimated effect. Thus, when interpreting the results above, it should be noted that these results may not hold for every patient. As an example, Figure 2 illustrates the heterogeneity in effects for the association between pain intensity and activity interference.
Figure 2 – Histogram of best linear unbiased prediction (BLUPs) for the association
between pain intensity and activity interference.
DISCUSSION
The aim of this study was to provide insight into the daily dynamics among pain intensity, negative affect, energy, and their association with activity interference in chronic migraine. All three symptoms were found to predict next-moment activity interference, of which pain intensity was the strongest predictor. Yet, next-moment activity interference was not found to be greater when symptoms co-occurred. Finally, pain intensity, negative affect, and energy were significantly interrelated.
Our findings are in line with previous cross-sectional studies which have shown that individuals with higher pain intensity and negative affect experience greater migraine-related interference (Buse et al., 2012; Holroyd et al., 2007). However, our study was the first to show that these associations also occur within a day, and that increases in symptom severity
Activity interference in chronic migraine _________________________________________________________________________ precede increases in activity interference. This finding suggests that targeting pain intensity and negative affect may indeed result in improved daily functioning in CM. To our knowledge, our study was also the first to demonstrate that low energy contributes to daily activity interference in chronic migraine. Findings of previous studies indicate that fatigue, which is similar to a lack of energy, is a frequently reported symptom in individuals with CM (Maizels & Burchette, 2004; Peres et al., 2002). Indeed, it is one of the most common symptoms during the premonitory and postdrome phases of a migraine attack (Giffin et al., 2003; Kelman, 2006).Our findings show that, in addition to intense pain during the migraine attack, such symptoms can significantly add to the burden of CM.
The finding that symptoms did not have an additive effect on activity interference appears to contradict the ‘Theory of Unpleasant Symptoms’, (Lenz et al., 1997) which poses that co-occurring symptoms have a stronger impact on functioning than a single symptom. Earlier studies investigating this assumption have only tested whether individuals with multiple symptoms report on average poorer functioning. For instance, a study in multiple sclerosis found that patients with high scores on pain, depression, as well as fatigue reported poorer quality of life than patients who did not report all three symptoms (Motl & McAuley, 2010). To our knowledge, our study is the first to actually test the additive effect of symptoms in daily life. Although the reasons for our non-significant finding is unclear, we speculate that in the context of chronic pain, especially in migraine, pain may have such a large impact on functioning that it supersedes the effect of other symptoms. Indeed, the effects of negative affect and energy on activity interference were smaller when also accounting for the influence of pain (see Table 3).
This study was the first to explore the mutual associations among pain intensity, negative affect, and energy in CM. Although all symptoms were found to be significantly interrelated, the most pronounced effects were found for the association between negative affect and moment pain intensity and energy, and the association between pain intensity and next-moment energy. Our findings build on previous cross-sectional studies which have found that negative affect is associated with a higher prevalence of fatigue and greater pain intensity in headache (Magnusson & Becker, 2003a; Maizels & Burchette, 2004). They also concur with an earlier study in which individuals with CM reported more severe fatigue compared to those with episodic migraine (Lucchesi et al., 2016). The temporal precedence of symptoms revealed in our study further suggest a potential downward spiral of more severe pain, lower energy, and greater activity interference, fueled by high negative affect. Thus, addressing negative affect may not only have a direct, but also an indirect effect on daily functioning by preventing decreases in energy and increases in pain intensity.
Results of this study may have implications for clinical practice. The finding that pain intensity was the strongest independent predictor of activity interference suggests that it should be a starting point for interventions aimed at improving daily functioning in CM. Indeed, reducing pain intensity (e.g., with analgesics and triptans) is typically one of the primary goals of treatment of headache attacks (Goadsby & Sprenger, 2010). However, also
Activity interference in chronic migraine
_________________________________________________________________________
Between subject variation in within-subject effects
To gain insight into heterogeneity of the estimated effects, best linear unbiased prediction (BLUP) was used to predict deviation from the fixed effects for each individual. Histograms of these predictions showed that the individual deviation from the fixed effects was not normally distributed. That is, for most coefficients, there appeared to be a subgroup of patients who demonstrated much smaller or larger effects than the estimated effect. Thus, when interpreting the results above, it should be noted that these results may not hold for every patient. As an example, Figure 2 illustrates the heterogeneity in effects for the association between pain intensity and activity interference.
Figure 2 – Histogram of best linear unbiased prediction (BLUPs) for the association
between pain intensity and activity interference.
DISCUSSION
The aim of this study was to provide insight into the daily dynamics among pain intensity, negative affect, energy, and their association with activity interference in chronic migraine. All three symptoms were found to predict next-moment activity interference, of which pain intensity was the strongest predictor. Yet, next-moment activity interference was not found to be greater when symptoms co-occurred. Finally, pain intensity, negative affect, and energy were significantly interrelated.
Our findings are in line with previous cross-sectional studies which have shown that individuals with higher pain intensity and negative affect experience greater migraine-related interference (Buse et al., 2012; Holroyd et al., 2007). However, our study was the first to show that these associations also occur within a day, and that increases in symptom severity
Activity interference in chronic migraine _________________________________________________________________________ precede increases in activity interference. This finding suggests that targeting pain intensity and negative affect may indeed result in improved daily functioning in CM. To our knowledge, our study was also the first to demonstrate that low energy contributes to daily activity interference in chronic migraine. Findings of previous studies indicate that fatigue, which is similar to a lack of energy, is a frequently reported symptom in individuals with CM (Maizels & Burchette, 2004; Peres et al., 2002). Indeed, it is one of the most common symptoms during the premonitory and postdrome phases of a migraine attack (Giffin et al., 2003; Kelman, 2006).Our findings show that, in addition to intense pain during the migraine attack, such symptoms can significantly add to the burden of CM.
The finding that symptoms did not have an additive effect on activity interference appears to contradict the ‘Theory of Unpleasant Symptoms’, (Lenz et al., 1997) which poses that co-occurring symptoms have a stronger impact on functioning than a single symptom. Earlier studies investigating this assumption have only tested whether individuals with multiple symptoms report on average poorer functioning. For instance, a study in multiple sclerosis found that patients with high scores on pain, depression, as well as fatigue reported poorer quality of life than patients who did not report all three symptoms (Motl & McAuley, 2010). To our knowledge, our study is the first to actually test the additive effect of symptoms in daily life. Although the reasons for our non-significant finding is unclear, we speculate that in the context of chronic pain, especially in migraine, pain may have such a large impact on functioning that it supersedes the effect of other symptoms. Indeed, the effects of negative affect and energy on activity interference were smaller when also accounting for the influence of pain (see Table 3).
This study was the first to explore the mutual associations among pain intensity, negative affect, and energy in CM. Although all symptoms were found to be significantly interrelated, the most pronounced effects were found for the association between negative affect and moment pain intensity and energy, and the association between pain intensity and next-moment energy. Our findings build on previous cross-sectional studies which have found that negative affect is associated with a higher prevalence of fatigue and greater pain intensity in headache (Magnusson & Becker, 2003a; Maizels & Burchette, 2004). They also concur with an earlier study in which individuals with CM reported more severe fatigue compared to those with episodic migraine (Lucchesi et al., 2016). The temporal precedence of symptoms revealed in our study further suggest a potential downward spiral of more severe pain, lower energy, and greater activity interference, fueled by high negative affect. Thus, addressing negative affect may not only have a direct, but also an indirect effect on daily functioning by preventing decreases in energy and increases in pain intensity.
Results of this study may have implications for clinical practice. The finding that pain intensity was the strongest independent predictor of activity interference suggests that it should be a starting point for interventions aimed at improving daily functioning in CM. Indeed, reducing pain intensity (e.g., with analgesics and triptans) is typically one of the primary goals of treatment of headache attacks (Goadsby & Sprenger, 2010). However, also
Activity interference in chronic migraine
_________________________________________________________________________ negative affect appears to be an important target for intervention, since our findings indicate that negative affect has both a direct and an indirect influence on activity interference. Cognitive behavioral therapy has been found to be effective in reducing negative mood and is recommended as a supplement to pharmacological interventions in CM (Butler, Chapman, Forman, & Beck, 2006; Smitherman, Maizels, & Penzien, 2008). Routine screening for negative affect in headache care, using brief screening instruments such as the PHQ-9 (Kroenke, Spitzer, & Williams, 2001), may help to identify patients for whom such interventions may be most beneficial (Smitherman et al., 2008).
This study has strengths and limitations. A major strength was the use of an intensive longitudinal design, which provided insight into within-subject variability in symptoms and daily functioning, as well as into their temporal precedence. A limitation was that the large majority of our sample was female, which may limit generalizability to male CM sufferers. Furthermore, to reduce the burden on participants, we limited our follow-up period to one week. A longer follow-up period may have allowed us to sample a greater symptom variation within a person and control for factors such as the hormonal cycle. Finally, there was substantial heterogeneity in the estimated within-subject effects. Future studies should take into account other variables, such as cognitive and behavioral coping strategies, that may account for this heterogeneity.
To conclude, this study found that pain intensity, negative affect, and energy interact, and in turn predict the interference of daily activities in the context of chronic migraine. Results contribute to a more accurate understanding of the way in symptoms interfere with daily functioning in this condition and highlight promising targets for intervention.
Activity interference in chronic migraine _________________________________________________________________________
References
Bolger, N., & Laurenceau, J. (2013). Intensive longitudinal methods: An introduction to diary and experience
sampling research. New York: Guilford Press.
Buse, D. C., Rupnow, M. F., & Lipton, R. B. (2009). Assessing and managing all aspects of migraine: Migraine attacks, migraine-related functional impairment, common comorbidities, and quality of life. Mayo Clinic
Proceedings, , 84(5) 422-435.
Buse, D. C., Manack, A., Serrano, D., Reed, M., Varon, S., Turkel, C., & Lipton, R. (2012). Headache impact of chronic and episodic migraine: Results from the american migraine prevalence and prevention study.
Headache, 52(1), 3-17.
Buse, D. C., Silberstein, S. D., Manack, A. N., Papapetropoulos, S., & Lipton, R. B. (2013). Psychiatric comorbidities of episodic and chronic migraine. Journal of Neurology, 260(8), 1960-1969.
Butler, A. C., Chapman, J. E., Forman, E. M., & Beck, A. T. (2006). The empirical status of cognitive-behavioral therapy: A review of meta-analyses. Clinical Psychology Review, 26(1), 17-31.
Csikszentmihalyi, M., & Larson, R. (1987). Validity and reliability of the experience-sampling method. The
Journal of Nervous and Mental Disease, 175(9), 526-536.
Dahlof, C., & Solomon, G. (1998). The burden of migraine to the individual sufferer: A review. European Journal
of Neurology, 5(6), 525-533.
de Vries, M. W. (1992). The experience of psychopathology in natural settings: Introduction and illustration of variables. In M. W. DeVries (Ed.), The experience of psychopathology: Investigating mental disorders in their
natural settings (pp. 3-26). Cambridge, UK: Cambridge University Press.
Emmons, R. A. (1999). The psychology of ultimate concerns: Motivation and spirituality in personality. New York: Guilford Press.
Fox, S. W., & Lyon, D. E. (2006). Symptom clusters and quality of life in survivors of lung cancer. Oncology
Nursing Forum, 33(5), 931-936.
Giffin, N., Ruggiero, L., Lipton, R., Silberstein, S., Tvedskov, J., Olesen, J., . . . Macrae, A. (2003). Premonitory symptoms in migraine - an electronic diary study. Neurology, 60(6), 935-940.
Goadsby, P. J., & Sprenger, T. (2010). Current practice and future directions in the prevention and acute management of migraine. Lancet Neurology, 9(3), 285-298.
Headache Classification Committee of the International Headache Society (IHS. (2013). The international classification of headache disorders, (beta version). Cephalalgia, 33(9), 629-808.
Holroyd, K. A., Drew, J. B., Cottrell, C. K., Romanek, K. M., & Heh, V. (2007). Impaired functioning and quality of life in severe migraine: The role of catastrophizing and associated symptoms. Cephalalgia, 27(10), 1156-1165.
Houtveen, J. H., & Sorbi, M. J. (2013). Prodromal functioning of migraine patients relative to their interictal state - an ecological momentary assessment study. Plos One, 8(8), UNSP e72827.
Kelman, L. (2006). The postdrome of the acute migraine attack. Cephalalgia, 26(2), 214-220.
Kroenke, K., Spitzer, R., & Williams, J. (2001). The PHQ-9 - validity of a brief depression severity measure.
Journal of General Internal Medicine, 16(9), 606-613.
Lenz, E. R., Pugh, L. C., Milligan, R. A., Gift, A., & Suppe, F. (1997). The middle-range theory of unpleasant symptoms: An update. Advances in Nursing Science, 19(3), 14-27.
Little, B. R., & Chambers, N. C. (2004). Personal project pursuit: On human doings and well-beings. In W. M. Cox, & E. Klinger (Eds.), Handbook of motivational counseling (pp. 65-79). West Sussex, England: John Wiley & Sons, Ltd.
Louter, M., Pijpers, J., Wardenaar, K., van Zwet, E., van Hemert, A., Zitman, F., . . . Terwindt, G. (2015). Symptom dimensions of affective disorders in migraine patients. Journal of Psychosomatic Research, 79(5), 458-463.
Activity interference in chronic migraine
_________________________________________________________________________ negative affect appears to be an important target for intervention, since our findings indicate that negative affect has both a direct and an indirect influence on activity interference. Cognitive behavioral therapy has been found to be effective in reducing negative mood and is recommended as a supplement to pharmacological interventions in CM (Butler, Chapman, Forman, & Beck, 2006; Smitherman, Maizels, & Penzien, 2008). Routine screening for negative affect in headache care, using brief screening instruments such as the PHQ-9 (Kroenke, Spitzer, & Williams, 2001), may help to identify patients for whom such interventions may be most beneficial (Smitherman et al., 2008).
This study has strengths and limitations. A major strength was the use of an intensive longitudinal design, which provided insight into within-subject variability in symptoms and daily functioning, as well as into their temporal precedence. A limitation was that the large majority of our sample was female, which may limit generalizability to male CM sufferers. Furthermore, to reduce the burden on participants, we limited our follow-up period to one week. A longer follow-up period may have allowed us to sample a greater symptom variation within a person and control for factors such as the hormonal cycle. Finally, there was substantial heterogeneity in the estimated within-subject effects. Future studies should take into account other variables, such as cognitive and behavioral coping strategies, that may account for this heterogeneity.
To conclude, this study found that pain intensity, negative affect, and energy interact, and in turn predict the interference of daily activities in the context of chronic migraine. Results contribute to a more accurate understanding of the way in symptoms interfere with daily functioning in this condition and highlight promising targets for intervention.
Activity interference in chronic migraine _________________________________________________________________________
References
Bolger, N., & Laurenceau, J. (2013). Intensive longitudinal methods: An introduction to diary and experience
sampling research. New York: Guilford Press.
Buse, D. C., Rupnow, M. F., & Lipton, R. B. (2009). Assessing and managing all aspects of migraine: Migraine attacks, migraine-related functional impairment, common comorbidities, and quality of life. Mayo Clinic
Proceedings, , 84(5) 422-435.
Buse, D. C., Manack, A., Serrano, D., Reed, M., Varon, S., Turkel, C., & Lipton, R. (2012). Headache impact of chronic and episodic migraine: Results from the american migraine prevalence and prevention study.
Headache, 52(1), 3-17.
Buse, D. C., Silberstein, S. D., Manack, A. N., Papapetropoulos, S., & Lipton, R. B. (2013). Psychiatric comorbidities of episodic and chronic migraine. Journal of Neurology, 260(8), 1960-1969.
Butler, A. C., Chapman, J. E., Forman, E. M., & Beck, A. T. (2006). The empirical status of cognitive-behavioral therapy: A review of meta-analyses. Clinical Psychology Review, 26(1), 17-31.
Csikszentmihalyi, M., & Larson, R. (1987). Validity and reliability of the experience-sampling method. The
Journal of Nervous and Mental Disease, 175(9), 526-536.
Dahlof, C., & Solomon, G. (1998). The burden of migraine to the individual sufferer: A review. European Journal
of Neurology, 5(6), 525-533.
de Vries, M. W. (1992). The experience of psychopathology in natural settings: Introduction and illustration of variables. In M. W. DeVries (Ed.), The experience of psychopathology: Investigating mental disorders in their
natural settings (pp. 3-26). Cambridge, UK: Cambridge University Press.
Emmons, R. A. (1999). The psychology of ultimate concerns: Motivation and spirituality in personality. New York: Guilford Press.
Fox, S. W., & Lyon, D. E. (2006). Symptom clusters and quality of life in survivors of lung cancer. Oncology
Nursing Forum, 33(5), 931-936.
Giffin, N., Ruggiero, L., Lipton, R., Silberstein, S., Tvedskov, J., Olesen, J., . . . Macrae, A. (2003). Premonitory symptoms in migraine - an electronic diary study. Neurology, 60(6), 935-940.
Goadsby, P. J., & Sprenger, T. (2010). Current practice and future directions in the prevention and acute management of migraine. Lancet Neurology, 9(3), 285-298.
Headache Classification Committee of the International Headache Society (IHS. (2013). The international classification of headache disorders, (beta version). Cephalalgia, 33(9), 629-808.
Holroyd, K. A., Drew, J. B., Cottrell, C. K., Romanek, K. M., & Heh, V. (2007). Impaired functioning and quality of life in severe migraine: The role of catastrophizing and associated symptoms. Cephalalgia, 27(10), 1156-1165.
Houtveen, J. H., & Sorbi, M. J. (2013). Prodromal functioning of migraine patients relative to their interictal state - an ecological momentary assessment study. Plos One, 8(8), UNSP e72827.
Kelman, L. (2006). The postdrome of the acute migraine attack. Cephalalgia, 26(2), 214-220.
Kroenke, K., Spitzer, R., & Williams, J. (2001). The PHQ-9 - validity of a brief depression severity measure.
Journal of General Internal Medicine, 16(9), 606-613.
Lenz, E. R., Pugh, L. C., Milligan, R. A., Gift, A., & Suppe, F. (1997). The middle-range theory of unpleasant symptoms: An update. Advances in Nursing Science, 19(3), 14-27.
Little, B. R., & Chambers, N. C. (2004). Personal project pursuit: On human doings and well-beings. In W. M. Cox, & E. Klinger (Eds.), Handbook of motivational counseling (pp. 65-79). West Sussex, England: John Wiley & Sons, Ltd.
Louter, M., Pijpers, J., Wardenaar, K., van Zwet, E., van Hemert, A., Zitman, F., . . . Terwindt, G. (2015). Symptom dimensions of affective disorders in migraine patients. Journal of Psychosomatic Research, 79(5), 458-463.
Activity interference in chronic migraine
_________________________________________________________________________
Lucchesi, C., Baldacci, F., Cafalli, M., Dini, E., Giampietri, L., Siciliano, G., & Gori, S. (2016). Fatigue, sleep-wake pattern, depressive and anxiety symptoms and body-mass index: Analysis in a sample of episodic and chronic migraine patients. Neurological Sciences, 37(6), 987-989.
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