FACULTEIT DER MAATSCHAPPIJ- EN GEDRAGSWETENSCHAPPEN Graduate School of Childhood Development and Education
MASTER ORTHOPEDAGOGIEK 2017-2018
MASTERSCRIPTIE
Comparison and Predictors of Parental Quality of Life:
A comparison of parents with children who have an autism spectrum disorder and comorbid anxiety disorder, exclusively an anxiety disorder and without psychopathology
Masterscriptie Orthopedagogiek Pedagogische en Onderwijskundige Wetenschappen Universiteit van Amsterdam W. Heller Begeleiding: Drs. E. A. Salvadori Tweede beoordelaar: Dr. F. J. A. van Steensel Amsterdam, augustus, 2018
Comparison and Predictors of Parental Quality of Life:
A comparison of parents with children who have an autism spectrum disorder and comorbid anxiety disorder, exclusively an anxiety disorder and without psychopathology
Masterscriptie Orthopedagogiek Pedagogische en Onderwijskundige Wetenschappen Universiteit van Amsterdam W. Heller Begeleiding: Drs. E. A. Salvadori Tweede beoordelaar: Dr. F. J. A. van Steensel Amsterdam, augustus 2018
Abstract
The first aim of this study was to compare the quality of life of parents with children with an autism spectrum disorder and comorbid an anxiety disorder (ASD +AD), with exclusively an anxiety disorder (AD) and without psychopathology (control group). The second aim was examining plausible predictors of parental quality of life at a child-, parent- and family-level. A total of 344 parents completed multiple questionnaires and were divided in three groups: 1) ASD + AD (N=132), 2) AD (N=123) and 3) control group (N=98). Results demonstrated that fathers’ quality of life differed significantly among the groups; with the highest quality of life in ASD + AD, and the lowest quality of life in the control group. Mothers’ quality of life did not differ significantly among the groups. Additionally, anxiety symptoms of parents were found to be a predictor of parental quality of life. In conclusion, children who have an AD or ASD positively affect fathers’ quality of life, and parents’
anxiety symptoms are associated with parental quality of life. For future studies and treatment interventions it is important to include parental- and family factors.
Samenvatting
Het eerste doel van het huidige onderzoek was om de kwaliteit van leven bij ouders die een kind hebben met een autismespectrumstoornis en comorbide angststoornis (ASS + AS), exclusief een angststoornis (AS) en zonder psychopathologie (controlegroep) te vergelijken. Het tweede doel was het onderzoeken van plausibele voorspellers van de kwaliteit van leven bij ouders op een kind-, ouder- en gezin -niveau. Een totaal van 344 ouders voltooide meerdere vragenlijsten en werden verdeeld in drie groepen 1) ASS + AS (N=132), 2) AS (N=123), en 3) controlegroep (N=89). Uit de resultaten bleek een significant verschil van de kwaliteit van leven van vader tussen de groepen; de hoogste kwaliteit van leven bij de ASS + AS groep en de laagste kwaliteit van leven bij de controlegroep. Er werd geen significant verschil gevonden van de kwaliteit van leven van moeder tussen de groepen. Tevens, bleken angstsymptomen van ouders een voorspeller te zijn voor hun eigen kwaliteit van leven. De bevindingen van de huidige studie suggereren dat kinderen met AS of ASS de kwaliteit van leven bij vaders positief beïnvloeden en dat de angstsymptomen van ouders een verband hebben met hun kwaliteit van leven. In toekomstige studies en behandelinterventies is het belangrijk dat ouderlijke en gezinsfactoren worden meegenomen.
Kernwoorden: ouderlijke kwaliteit van leven, angststoornis, autismespectrumstoornis, comorbiditeit
Introduction
The concept of quality of life is problematic, and there exists no universally accepted definition (Coghill, Danckaerts, Sonuga-Barke, & Sergeant, 2009; Eriksson & Lindström, 2007). There is a general agreement in believing that because of the multidimensionality and complexity of quality of life it is problematic to capture (Eriksson & Lindström, 2007). The World Health Organization Quality of Life group (1995) described quality of life as “the individual’s perception of their position in life, in the context of culture and value systems in which they live, and in relation to their goals, expectations, standards and concerns” (p. 1405). A decade later Cummins (2005) conceptualized quality of life as “a construct that: 1) is multidimensional and influenced by personal and environmental factors and their interactions; 2) has the same components for all people; 3) has both subjective and objective components; and 4) is enhanced by self-determinations, resources, purpose in life, and a sense of
belonging” (p. 700). Whereas, Eriksson and Lindström (2007) attempted to define quality of life as “a personal being or satisfaction with life, as well as physical and material well-being, relations with other people, social, communal, civic activities, personal development and fulfillment, positive mental health, a degree of goodness, and is related to health-related quality of life (p. 939).
Quality of life has consistently been demonstrated to be lower in parents who have children with clinical disabilities (Bode, Weidner, & Storck, 2000). Crucially, children with autism spectrum disorder (ASD)1 were found to be particularly challenging for parents, because parents of children with ASD face additional challenges not experienced by other parental groups (Falk, Norris, & Quinn, 2014). An increasing number of studies examined the quality of life in parents of children with ASD (Allik, Larsson, & Smedje, 2006; Eapen & Guan, 2016; Lee et al., 2009; Mugno, Ruta, D’Arrigo, & Mazzone, 2007; Rattaz, Michelon, Roeyers, & Baghdadli, 2016), reporting that parents of children with ASD experience higher levels of stress and significantly lower levels of adaptive coping and resources, compared to parents of typically developing children (Rao & Beidel, 2009). Findings of a cohort study showed that two-thirds of parents of young adults with ASD (66.7%) reported that their quality of life was -at least- moderately altered as a consequence of having a child with ASD, providing evidence for the suggestion that the impact of ASD on families remains strong even when children grow up and become young adults (Rattaz et al., 2016). Having a child with
1 ASD is a neurodevelopmental disorder that is characterized by impairment in social communication and
interaction, and by restricted and repetitive behavior, present in early childhood (American, Psychiatric Association, 2013)
high functioning autism negatively influences parents’ quality of life (Lee et al., 2009), not only compared to parents of typically developing children, but also to parents of children with other disabilities. For example, Mugno et al. (2007)’s study reported that parents of children with ASD, and particularly mothers, experience more stress than parents of typically
developing children or other clinical conditions, such as cystics fibrosis, Down syndrome, behavior disorder, mental retardation, learning disability. The differences in quality of life between parents of children with ASD and parents of children with other clinical diagnoses could be attributed to the environmental effects (greater stresses and burden) of having a child with such severe developmental disorders: difficult behaviors, including temper tantrum and aggressive, self-abusive, destructive, obsessive, ritualistic, impulsive and self-stimulatory behaviors; limited social skills and judgment that often resulted in being teased or rejected; the strain of not understanding their children or knowing what was wrong with them; constant needed supervision and assistance with daily living skills; financial strains; the problems associated with school and relative services; difficulty obtaining a correct diagnoses; stressful experiences with professionals; worries about the future, including living arrangements and sexuality; ineffective services and unmet needs; poor communication and coordination among services providers (Mugno et al., 2007).
Not only individual parent’s quality of life seems to be impaired when having children with ASD, but the whole family functioning is more restricted, as compared to families with children without a psychological disorder (Friedmann et al., 1997). According to Johnson & Simpson (2017) family functioning can be defined as “a set of basic attributes that describe and explain how a family system typically appraises, operates, or behaves and it includes supportive relationships among parents, family members, friends, and community members” (p. 221). As part of the biopsychosocial model of major illness, there has been a growing recognition over the past several decades that psychiatric disorders are often associated with significant higher family dysfunction (Friedmann et al., 1997).
Additionally, child-parent interactions in families with a child with ASD seem to be impaired as well. A meta-analysis by Rutgers, Bakermans- Kranenburg, van IJzendoorn and van Berckelaer-Onnes, (2004) found that children with ASD are less often securely attached to their parents than children without ASD (Rutgers et al., 2004). Attachment is a biologically based system that promotes the proximity between child and caregiver and serves the
evolutionary purpose of protecting the child from danger (Colonnesi et al., 2011). When caregivers are consistently sensitive to the infant’s attachment behaviors, the infant perceives the caregiver as a safe haven and a secure base from which to explore the environment. This
condition has been designated as secure attachment. On the contrary, when caregivers show a lack of sensitivity or inconsistent sensitivity, infants do not perceive their parents as a safe haven and secure base, and develop an insecure type of attachment (Bowlby, 1973 in Colonnesi et al., 2011).
Although many studies have been investigating the consequences of having a child with ASD in the family, examining them at several levels (e.g., parental quality of life, family functioning, attachment patterns), surprisingly little is known about ASD comorbidity. Recent research indicates that anxiety symptoms occur at higher rates in youth with ASD (de Bruin, Ferdinand, Meester, Nijs, & Verheij, 2007; Leyfer et al., 2006; van Steensel, Bögels, & Perrin, 2011). Comorbidity estimates of anxiety disorders are nearly 40% among children and adolescents with ASD (van Steensel et al., 2011). The possibility for ASD symptoms to overshadow an anxiety disorder represents an ongoing clinical and empirical challenge (Wood & Gadow, 2010). Social awkwardness and avoidance, compulsive and ritualistic behavior, communication deficits, and reduced emotional reciprocity represent areas of symptom overlap between anxiety and ASD (Wood & Gadow, 2010). Anxiety is not typically pathological as it is adaptive in many scenarios when it facilitates avoidance of danger
(Beesdo, Knappe, & Pine, 2009). However, when such reaction becomes excessive and impairs a person’s daily functioning, one is classified as having an anxiety disorder
(American Psychiatric Association, 2013). Anxiety disorders are among the most common disorders in childhood and adolescence (Costello, Egger, & Angold, 2005; Walkup et al., 2008). Despite notable variation in prevalence estimates, likely due to differing methods for obtaining these estimates, the lifetime prevalence of ‘any anxiety disorder’ in studies with children or adolescents is about 15 to 20% (Beesdo et al., 2009).
Studies found that children with anxiety disorders have a poor quality of life
(Bastiaansen, Koot, Ferdinand, & Verhulst, 2004; Olatunji, Cisler, & Tolin, 2007). Although clinicians may consider anxiety disorders less severe than other child psychiatric disorders, Bastiaansen et al. (2004) found that the impact on quality of life is being equal to children with externalizing behavior disorders and mood disorders. According to both parents and clinicians report, they even have a poorer quality of life on emotional functioning compared to other disorders. Olatunji et al. (2007) meta-analysis examined the impact of anxiety disorders on quality of life by comparing clinically anxious patients with a nonclinical control. Findings suggested that the subjective views of patients with anxiety disorders regarding the value of their life circumstances, including perceptions of health, social
relationships, occupation, home and family life, are significantly lower than the perceived quality of life in people without an anxiety disorder.
Moreover, patients with anxiety disorders are less likely to exchange information in the communication dimension. These patients showed impaired levels of family functioning, communication, affective responsiveness, affective involvement, behavior control and general function when compared to non-clinical individuals (Wang, Chen, Tan, & Zhao, 2016).
Besides family function, there is as well an association between insecure attachment and child/adolescent anxiety (Colonnesi et al., 2011). It has been shown that insecurely attached children are less able to resolve social problems and to establish and maintain friendships. They may also experience more rejections and receive less support from peers or caregivers and tend to show a low capacity for self-regulation, which is reflected in lower levels of ego-control and ego-resiliency. These characteristics could make insecurely attached children relatively vulnerable to developing anxiety disorders (Colonnesi et al., 2011).
Another characteristic for developing anxiety disorders is parental anxiety. Children of parents with anxiety disorders are more likely to develop anxiety problems than children of parents without anxiety disorders (Beidel & Turner, 1997). This can be explained by a
biological vulnerability, exposure to adverse life events and chronic stress, and different types of learning processes (McLeod, Wood, & Weisz, 2007). An example of learning processes is that children observe their parent’s behavior and may internalize their parents maladaptive cognitive. In fact, clinically anxious children interpret ambiguous situations as significantly more threatening than non-anxious children, and maternal and child threat interpretations are significantly correlated (Creswell, Schniering, & Rapee, 2005).
Anxiety disorders are common disorders with a substantial personal, social and economic burden. Anxiety disorders, along with quality of life issues have been largely neglected and less focused on (Hansson, 2002). Indeed, although the quality of life in children with anxiety disorders has been examined, surprisingly little research has been conducted to examine the parental quality of life among parents who have children with anxiety disorders. This seems essential, as parents of children with anxiety disorders often spend time and energy accommodating their child’s symptoms and such accommodation is associated with higher levels of parent stress and psychopathology (Kerns et al., 2015; Lebowitz et al., 2013), which in turn impacts parental quality of life (Eapen & Guan, 2016). Additionally, relatively few studies have assessed impairments associated with ASD comorbid anxiety disorders, particularly in domains of difficulty than can be seen across both disorders (Kerns et al., 2015). The interest in the prevalence, presentation, and treatment of anxiety disorders in
individuals with ASD has grown (Kerns et al., 2015). However, it is not yet clear if patients with anxiety disorders comorbid with psychiatric conditions have significantly poorer quality of life than those without psychiatric comorbidity (Olatunji et al., 2007). It is important to measure the impact on parental quality of life given the prolonged and multidimensional care need of children with AD or ASD and the possibility of increased levels of caregiving stress may exert negative effect on parents’ and their children’s adaption outcomes (Carona, Silva, Crespo & Canavarro, 2014; Hoefman et al., 2014).
Accordingly, the aim of the current study was to investigate parental quality of life, comparing parents who have children with 1) an ASD and comorbid AD, 2) exclusively an AD, 3) without psychopathology (i.e., control group), examining the predictors of parental quality of life at a family-, parent- and child- level. Two main research questions and hypotheses were tested:
1. Does the overall quality of life in mothers and fathers with children who have 1) an ASD and comorbid AD, 2) exclusively an AD, or 3) control group differ from each other? We expected that the overall quality of life in mothers and fathers with children who have ASD and comorbid AD would be the most impaired, followed then, in order, by parents who have a child with exclusively an AD and parents with a child without psychopathology
2. Does the child’s- autism and anxiety -symptoms, attachment of the child, parental anxiety symptoms and family functioning predict parental overall quality of life? Based on previous literature, it was expected that child’s autism and anxiety -symptoms, attachment of the child, parental anxiety symptoms and/or family functioning predict parental overall quality of life (Beidel & Turner,1997; Colonnesi et al., 201; Creswell et al., 2005; Wang et al., 2016).
Method Participants
A total of 344 parents were included in the study and divided in three groups: 1) parents of a child with an autism spectrum disorder comorbid an anxiety disorder (ASD + AD), (N = 132), 2) parents of a child with exclusively an anxiety disorder (AD, N = 123), 3) parents with a child without psychopathology (control group, N = 89). The age of the children and adolescents ranged from 7 to 18 years (M = 12.02, SD = 2.87) of whom 134 girls (39%) and 210 boys (61%) were participating in the study. Table 1 shows the demographic
Dutch mental health institutions and were participants in a study about the efficacy of cognitive behavioral therapy (CBT) (van Steensel & Bögels, 2015). The research of van Steensel and Bögels (2015) consists a pre-test (interview, questionnaires), a post-test (after CBT), follow up after three months (after CBT), follow-up after one year (after CBT) and follow-up after two years (after CBT). This current study is a part of this research and used only data of the pre-measurement. Inclusion criteria for the study were: 1) having at least one anxiety disorder, and 2) at least one parent willing to participate. Exclusion criteria were: 1) IQ level below 70, 2) untreated psychotic disorder, 3) acute suicidal risk, and 4) current sexual or physical abuse. Participants of the control group were recruited via schools, day-care facilities and convenience sampling by graduate students of the University of
Amsterdam. Exclusion criteria of the control group were: 1) IQ <70, and 2) a DSM-IV disorder. The study was approved by a Medical Ethical Committee, and written consent was obtained
Procedure
Families of children of the ASD + AD group and AD group were asked to participate in a longitudinal study which examined the treatment of anxiety disorders in children with and without ASD, as compared to a control group. The DSM-IV-TR clinical diagnoses of ASD and AD were established by a multidisciplinary team of psychologists, therapists, social workers, and psychiatrists, at the mental health care centers. As part of the research
measurements, the presence of at least one anxiety disorder was confirmed with the Anxiety Disorder Interview Schedule-Child and Parent version (ADIS-C/P) for all children. In addition, the Autism Diagnostic Interview-Revised (ADI-R) was completed by the parents. Assessment took place at the mental health care center or at the family’s home. Seven mental health-care centers throughout the Netherlands participated, and each center had an
administrator who worked and/or conducted research within that center. The administrators were independent of the staff who initially established the diagnoses.
Measures and Instruments
Parental Quality of Life. Parents were asked to complete the Survey of Self-Rated Health, Wellness and Quality of Life (SRHWQ), an instrument used to assess health-related quality of life (Blanks, Schuster, & Dobson, 1997). It consists a total of 55 items that assess wellness through patients’ self-rating different health domains and overall quality of life. The follow domains were used to assess health, wellness and overall quality of life: 1) physical state, 2) mental/emotional state, 3) stress evaluation, 4) life enjoyment, 5) overall quality of life by Woodruff and Conway (1992). Both physical state (10 items; e.g. ‘Feeling of tension
or stiffness or lack of flexibility in your spine’) and mental/emotional state (10 items; e.g. ‘Presence of negative or critical feeling about yourself’) was rated on a frequency scale of 1 to 5 (1= never, 2= rarely, 3= occasionally, 4= regularly, and 5= constantly). Stress evaluation (10 items; e.g., ‘Work’) was completed with a 5-point Likert scale (1= none, 2= slight, 3= moderate, 4= pronounced, and 5= extensive). At life enjoyment (11 items; e.g., ‘Experience of relaxation or ease or well-being’) parents were asked to rate their feelings and experiences contributing to a broad sense of inter- and intra-personal enjoyment on a 5-point degree scale (1= never, 2= rarely, 3= occasionally, 4= regularly, and 5= constantly). Finally, the overall quality of life by Woodruff and Conway (1992) was measured. These items were represented in a 7-point scale (1= terrible, 2= unhappy, 3= mostly dissatisfied, 4= mixed, 5= mostly satisfied, 6= pleased, and 7= delighted). Cronbach’s alpha coefficients are above acceptable levels (i.e., >70), indicating strong internal consistency, that is, an interpretable underlying theme for the scale items of each wellness domains and overall quality of life (Blanks, Schuster & Dobson, 1997).
Child’s Autism Spectrum Disorder. Parents completed the Dutch version of the Children’s Social Behavior Questionnaire (CBSQ), the Vragenlijst voor Inventarisatie van Sociaal Gedrag van Kinderen (VISK) (Hartman, Luteijn, Serra & Minderaa, 2006; Luteijn, Minderaa & Jackson, 2002). The VISK is a 49-item questionnaire for parents or caregivers of children with pervasive development disorders. Parents were asked whether the described behavior applied to their child’s in the preceding two months (e.g.; ‘Has little or no need for contact for contact with others’), using a 3-point scale ‘does not apply’ (score 0), ‘sometimes or somewhat applies’ (score 1), or ‘clearly or often applies’ (score 2). The items are divided into six subscales, referring to 1) behaviors not tuned to situation, 2) withdrawal, 3)
orientation problems, 4) difficulties understanding social information, 5) stereotyped behaviors, and 6) fear of and resistance to change. The VISK is a valid and reliable
instrument, with a good internal consistency of the total scale, equal to Cronbach’s alpha of .94 for the 49 items. The internal consistencies of the subscales were also good: Subscale 1 ‘‘not optimally tuned to the social situation’’ (α = .90); Subscale 2 ‘‘reduced contact and social interest’’ (α = .85); Subscale 3 ‘‘orientation problems in time, place, or activity’’ (α = .84); Subscale 4 ‘‘difficulties in understanding social information’’ (α = .85); Subscale 5 ‘‘stereotyped behavior’’ (α = .76); and Subscale 6 ‘‘fear of and resistance to changes’’ (α = .85) (Hartman, Luteijn, Serra, & Minderaa, 2006).
Child’s Anxiety Disorder. In order to measure anxiety symptoms, parents were asked to complete the Screen for Anxiety Related Emotional Disorder-71 (SCARED-71) (Bodden,
Bögels & Muris, 2009). The SCARED-71 consists of 71 descriptions of anxiety symptoms, clustered in seven subscales: 1) specific anxiety (15 items; e.g., ‘I am afraid of heights’), 2) separation anxiety (12 items; e.g., ‘I follow my mother or father wherever they go’), 3) social anxiety (9 items; e.g., ‘I’m afraid I will make a fool of myself when I’m with others’), 4) generalized anxiety (9 items; e.g., ‘I am a worrier.’ ), 5) panic disorder (13 items; e.g., ‘When I feel frightened, it is hard to breath’), 6) obsessive-compulsive disorder (9 items; e.g., ‘I do things more than twice in order to check whether I did it right’), 7) and post-traumatic stress disorder (4 items; e.g., ‘I have frightening dreams about a very aversive event I once
experienced.’). Parents were asked to rate each item in terms of how a particular symptom is endorsed, using a 3-point scale (0=almost never; 1=sometimes; 2=often). Cronbach’s alpha coefficients of the total score were generally high, indicating a high degree of homogeneity. The internal consistencies of the subscales were moderate to high, with values ranging from .64 to .93. The Cronbach’s alpha was .96 for mothers and .95 for fathers (Bodden et al., 2009).
Parental Anxiety Symptoms. The SCARED-Adult version (SCARED-A) was used to measure self-reported anxiety symptoms of fathers and mothers. This questionnaire has the same number of items and uses the same 3-point rating scale as the SCARED-71.
Psychometric properties are good and the internal consistency of the total score is high for both mothers (α = .93) as fathers (α = .93) (Bögels & van Melick, 2004).
Family Functioning. The Family Functioning Scale (FFS) measures family functioning, which is a factor-analytic version of four family questionnaires: 1) the Family Environment Scale, 2) the Family Concept Q Sort, 3) the Family Adaptability and Cohesion Evaluation Scales, and 4) the Family Assessment Measure (van Steensel, Zegers, & Bögels, 2017). The FFS is a questionnaire that was completed by both parents and children and contains 60 items rated on a 4-point scale (1=very untrue; 2 = fairly untrue; 3=fairly true; 4=very true). Two main dimensions were derived: family relationship (e.g., ‘family members really helped and supported one another’) and system maintenance/family control (e.g., ‘there was strict punishment for breaking rules in our family’). A higher score on the dimension of family relationship indicated a more cohesive, expressive outgoing and supportive family. A higher score on the dimension system maintenance/family control indicates a less organized, more hierarchical (and authoritarian) family, with a higher external locus of control and more enmeshment (van Steensel et al., 2017). Cronbach’s alpha for family relationship was .95 and .83 for system maintenance/family control (van Steensel et al., 2017).
Attachment. Both parents and children completed the Attachment Questionnaire for Children (AQ-C). The AQ is a 1-item self-report measure of children’s attachment style (Muris, Meesters, van Melick, & Zwambag, 2001). The AQ-C is based on Hazan and
Shaver’s (1987) single item measure of adult attachment style. Children and parents are given three descriptions of feelings and perceptions about relationships with other children and are asked to choose the description that best fits the child: 1) ‘I find it easy to become close friends with other children. I trust them and I am comfortable depending on them. I do not worry about being abandoned or about another child getting too close friends with me’ (secure attachment); 2) ‘I am uncomfortable to be close friends with other children. I find it difficult to trust them completely, difficult to depend on them. I get nervous when another child wants to become close friends with me. Friends often come closer to me than I want them to’ (avoidant attachment); and 3) ‘I often find that other children do not want to get as close as I would like them to be. I am often worried that my best friend doesn’t really like me and want to end our friendship. I prefer to do everything together with my best friend.
However, this desire sometimes scares other children away’ (ambivalent attachment). In this study, the AQ-C was dichotomized after parents had chosen one of the three descriptions. That is, secure attachment was recoding as 0, whereas avoidant and ambivalent attachment were both recodes as 1.
Table 1
Demographic Characteristics
Variables AD + ASD AD Control
% M (SD) % M (SD) % M (SD)
Mother age 42.25 (5.03) 43.12 (4.89) 42.30 (5.57)
Mother education level
Primary school 0 2.7 1.3 LBO 16.7 17.3 12.7 MVO 16.7 20.9 7.6 HVO 5.6 10 7.6 MBO 31.5 26.4 25.3 VWO 0 0.9 2.5 HBO 28.7 20 31.6 WO 0.9 1.8 11.4
Mother marital status
Married/living together 82.7 83.6 72.5 Unmarried/single 1.8 0.9 5 Divorced/single 8.2 6.4 17.5 Divorced/married again 7.3 3.6 5 Widow 0 5.5 0 Father age 44.02 (5.14) 45.58 (5.24) 45.68 (5.65)
Father education level
No education 1.1 1.1 0 Primary school 1.1 2.2 0 LBO 13.0 19.8 6.8 MVO 6.5 12.1 4.5 HVO 3.3 3.3 2.3 MBO 37.0 30.8 36.4 VWO 1.1 2.2 0 HBO 27.2 18.7 40.9 WO 9.8 8.8 9.1
Father marital status
Married/living together 91.4 93.5 100 Unmarried/single 0 4.3 0 Divorced/single 5.4 2.2 0 Divorced/married again 3.2 0 0 Child gender Female 23.5 49.2 47.8 Male 76.5 50.8 52.2 Child age 11.39 (2.63) 12.79 (2.72) 11.88 (3.15)
Analyses approach Statistical Strategy
The first research question, namely whether the overall quality of life in parents of children with an ASD and comorbid AD, exclusively an AD and without psychopathology differ from each other, was addressed by performing a one-way analysis for variance
(ANOVA). Expected was that the overall parental’ quality of life of these three groups differ from each other. Additionally, it was expected that the quality of life in parents who have a child with an ASD and comorbid AD was the most impaired, subsequently parents who have a child with exclusively an AD and parents with a child without psychopathology have likely a higher quality of life.
The second research question was, if the child’s- autism and anxiety -symptoms, attachment of the child, parental anxiety symptoms and family functioning predict parental overall quality of life. It was expected that the child’s- autism and anxiety -symptoms,
attachment of the child, parental anxiety symptoms and/or family functioning predict parental overall quality of life. Both ANOVA and multiple regression analyses were conducted for the quality of life of mothers and fathers. There were different outcomes of the multiple
regression analyses before and after the multiple imputation and transforming outliers. It was chosen to include these results before these statistical techniques as well, to provide
comprehensive data interpretation.
Missing values and outliers
All data were analyzed using Statistical Package for the Social Sciences (SPSS). Preliminary investigations indicated a total of 22.4% missing data on 16 variables. Multiple Imputation (MI) was performed to estimate them. MI is a general statistical method for the analysis of incomplete data sets. A MI procedure replaces each missing value with a set of plausible values that represent the uncertainty about the right value to impute. To perform five imputations is adequate (Rubin, 1996). Therefore, in this study five imputations were
executed and subsequently pooled estimates were calculated and used for the analyses. Detections of univariate outliers (i.e., those extreme values that deviate from 3 SD from the mean), revealed the presence of outliers on 11 variables. To deal with outliers, all the values were transformed into standardized Z scores; when the standardized Z score falls outside the confidence interval bounded by -3.29 and +3.29, then the value is possibly an outlier (Field, 2009). These outliers were transformed into the highest (or lowest) acceptable value, within their own group.
Assumptions
The one-way analyses of variance (ANOVA) is robust to violate assumptions.
Nevertheless, to draw conclusions about a population based on a regression analysis done on a sample, several assumptions must be met (Field, 2009). The parental quality of life was normally distributed for the ASD comorbid anxiety group, as assessed by Shapiro-Wilk’s test (p >.05), the control group and only anxiety group were not (p < .05). The assumption of homogeneity of variances was met, as assessed by Levene’s test for equality of variances (p = .635). Not all of the assumptions of the ANOVA were met, i.e. violations of normality. No statistical transformations were applied to the data, because of the large sample size and ANOVA is robust for violating assumptions.
Two multiple regression analyses were conducted, separated for mothers and fathers’ overall quality of life (dependent variables), with method ‘Enter’, which means the predictor variables are simultaneously included in the analyses. The independent variables were: 1) attachment, 2) anxiety symptoms child, 3) autism symptoms child, 4) anxiety symptoms of the parent, 5) family functioning: relationship dimension and 6) family functioning: family control. All the independent variables were continuous except for attachment. The
assumptions relate to the measurement where the multiple regression should have one continuous dependent variable and two or more independent variables that are measured at either continuous or nominal level. This study design met these two assumptions, because the dependent variable of both multiple regression analyses is continuous (scale) and there were six independent variables. There was independence of residuals in the original database, as assessed by a Durbin-Watson test (for mothers a statistic of 2.176 and fathers 2.321). Linearity was met as well, assessed by partial regression plots and a plot of studentized residuals against the predicted values. There was no evidence of multicollinearity, determined by tolerance values greater than 0.1. The assumption of normality and homoscedasticity of residuals was met. This means that all assumptions have been met. When the assumptions of regression are met, the model can be accurately applied to the population of interest (Field, 2009).
Results Mothers’ overall quality of life
A one-way ANOVA was conducted to determine whether the overall quality of life of mothers was different with respect to the three groups: 1) having a child with an autism spectrum disorder and comorbid anxiety disorder (ASD + AD), 2) having a child with
group). Pooled estimates were calculated, based on the missing value multiple imputations, and used for the final analyses. The results of the one-way ANOVA where mothers’ overall quality of life was investigated revealed nonsignificant difference between the groups in all of the five imputations (p > .05).
In order to investigate into the impact of different independent variables on one dependent variable, a multiple regression analysis was conducted. The results of the multiple regression of all of the five imputations were significant and the pooled estimated showed that mothers’ anxiety symptoms were a significant predictor of maternal quality of life (p < .01). In addition, a marginal negative effect for a dimension of family functioning, namely the relationship dimension, was spotted, suggesting that the less family members supported each other, the more mothers experienced an impaired quality of life. Results of the multiple regression without transforming outliers, nor imputating missingness showed a significant effect of relationship dimension. However, this is still a marginal effect and should be investigated further. Regression coefficients and standard errors can be found in Table 2 and Table 3.
Table 2
Summary of Pooled Estimates Multiple Regression Mothers’ Overall Quality of Life
Variable B SEB Sig
Intercept 48.594 15.521 .008
Attachment -1.265 1.859 .503
Anxiety symptoms child .007 .034 .849
Autism symptoms child -.036 .038 .357
Anxiety symptoms mother .159 .043 .000*
Relationship dimension -.203 .095 .053**
Family control .127 .135 .359
Table 3
Results of the Multiple Regression Without Transforming Outliers, Nor Imputating Missingness
Variable B SEB Sig
Intercept 67.030 13.700 .000
Attachment -1.194 1.417 .401
Anxiety symptoms child -.010 .042 .811
Autism symptoms child -.027 .057 .637
Anxiety symptoms mother .249 .049 .000*
Relationship dimension -.401 .086 .000*
Family control .107 .129 .407
Note. * p < .05; ** p < .10; B = unstandardized regression coefficient; SEB = Standard error of the coefficient Fathers’ overall quality of life
The results of the one-way ANOVA where fathers’ overall quality of life was analyzed revealed significant differences among the groups (p < .005). In order to further explore such differences, Tukey post hoc test were used because the Tukey post hoc test is powerful when testing large numbers of means (Field, 2009). The Tukey post hoc test revealed that the difference between the groups AD and ASD +AD was statistically
significant (p < .044) alongside with ASD +AD and the control group (p < .024) in all of the five imputations. Figure 1 showed the results of the one-way ANOVA, whereas the higher the score, the higher parental quality of life.
Note. * p < .05
The results of the multiple regression of fathers’ overall quality of life were not found significant at a p of .05. Nevertheless, a marginally significant effect of the parents’ anxiety symptoms was also spotted for fathers, indicating that the more anxiety fathers experience, the higher their overall quality of life is. None of the other variables tested in this study (i.e., attachment, anxiety symptoms child, autism symptoms child, relationship dimension and family control) were not predictive of fathers ‘overall quality of life. The results of the multiple regression without transforming outliers, nor imputating missingness showed two significant predictors; i.e. fathers’ anxiety symptoms and the relationship dimension of family functioning. Regression coefficients and standard errors are reported in Table 4 and 5.
Table 4.
Summary of Pooled Estimates Multiple Regression Fathers’ Overall Quality of Life
Variable B SEB Sig
Intercept 37.641 12.273 .007
Attachment -.91 1.163 .937
Anxiety symptoms child -.006 .031 .845
Autism symptoms child .009 .049 .851
Anxiety symptoms father .098 .053 .074**
Relationship dimension -.128 .076 .105
Family control .174 .141 .244
Note. * p < .05; ** p < .10; B = unstandardized regression coefficient; SEB = Standard error of the coefficient Table 5.
Results of the Multiple Regression Without Transforming Outliers, Nor Imputating Missingness
Variable B SEB Sig
Intercept 48.337 15.177 .002
Attachment -2.791 1.525 .701
Anxiety symptoms child -.031 .046 .510
Autism symptoms child -.048 .075 .522
Anxiety symptoms father .194 .068 .005*
Relationship dimension -.257 .094 .007*
Family control .253 .168 .135
Discussion
Despite the increasing interest in quality of life of children with disabilities, in
particular with autism spectrum disorder (ASD), studies have only recently begun to focus on parental quality of life. The first aim of this study was to explore whether there is a difference in parental quality of life, depending on the child’s condition. Specifically, the present study investigated differences among parents of children with an autism spectrum disorder and comorbid anxiety disorder (AD +ASD) and parents of children with exclusively an anxiety disorder (AD), confronting their perceived quality of life with those of parents who had children without psychopathology (control group). The second aim was to gain insight in those child-, parent- and family- related factors that could be predictive of parental quality of life.
Recent research indicates that anxiety symptoms occur at higher rates in youth with ASD. Comorbidity estimates of anxiety disorders are nearly 40% among children and
adolescents with ASD (van Steensel, Bögels, & Perrin, 2011). Although previous studies have been investigating the consequences of having a child with ASD in the family, examining family-related factors at several levels (e.g., attachment patterns, parental anxiety symptoms, family functioning), surprisingly little is known about the specific consequences of having a child with ASD comorbidity (Allik, Larsson, & Smedje, 2006; Eapen & Guan, 2016; Lee et al., 2009; Mugno, Ruta, D’Arrigo, & Mazzone, 2007; Olatunji, Cisler, & Tolin, 2007; Rattaz, Michelon, Roeyers, & Baghdadli, 2016). Furthermore, despite the fact that there is a high rate of comorbid AD in individuals with ASD, little is known about the effect of such comorbidity as well on maternal and paternal quality of life. Studies comparing children with ASD to clinically anxious children are sparse. Children with AD and ASD demand prolonged and multidimensional care possibly increasing levels of caregiving stress which may exert a negative effect on parents’ and their children’s adaptions outcomes (Carona, Silva, Crespo & Canavarro, 2014; Hoefman et al., 2014). Therefore, to identify this effect and possible causes, we found it meaningful to investigate the differences between the conditions and explore the underlying predictors of parental quality of life.
Based on previous findings, we expected that: a) the overall quality of life of parents with children who have an ASD and comorbid AD, exclusively an AD, and when compared to children without psychopathology (control group), would differ; with the quality of life of parents who have a child with an ASD and comorbid AD being the most impaired, followed then, in order, by parents who have a child with exclusively an AD and parents with a child without psychopathology; b) children-related factors, such as symptoms of anxiety and autism
and attachment style, parental anxiety symptoms, and family functioning would predict parental overall quality of life. These hypotheses were investigated for fathers and mothers separately, so to include gender differences in this study as well.
With regards to the first hypothesis, the current study found that fathers’, but not mothers’ overall quality of life, was significantly lower when having a child without psychopathology, subsequently fathers with a child with AD and the highest quality of life when the child had a comorbidity condition with ASD. These findings are inconsistent with previous literature suggesting that parents of children with an ASD have a poorer quality of life compared to parents of typically developing children, as well as compared to parents of children with other disabilities (Allik et al., 2006; Eapen, & Guan, 2016; Lee et al., 2009; Mugno et al., 2007; Rattaz et al., 2016). Moreover, Watson, Swan and Nathan (2011) found that quality of life worsens with increasing comorbidities. Two or more comorbidities show additional burden relative to the principal diagnosis alone. Surprisingly, this study found contradictory findings and indicate that fathers with a child with an ASD and comorbid an AD have a higher quality of life then those with a child without psychopathology. An explanation for these findings could be the adaptation and resilience of the parents in our study. There is increasing evidence that families of children with disabilities demonstrate a great degree of strength, expressing the positive contribution of disability to their family’s life and wellbeing (Skinner et al. 1999; Scorgie & Sobsey, 2000; Taunt & Hastings, 2002;
Hastings et al. 2005). Parents who have children with special needs appear to cope well with added demands, and remain relatively resilient. Many parents raising children with chronic health conditions and developmental disabilities report high satisfaction and enjoyment of their role (Barnett, Clements, Kaplan-Estrin & Fialka, 2003). Bayat (2007) provides evidence that, despite extraordinary challenges faced by families of children with autism, a number of these families show evidence of resilience. Another explanation of these findings could be the measurement of quality of life. Perhaps the items of the questionnaire are not affected by a child having an ASD and comorbid an AD, suggesting that other factors that are not measured relate to quality of life as well. There exists no universally accepted definition of quality of life and the measurement of this concept is various. Quality of life is a broad domain and multiple factors are involved. When looking into the items of the overall quality of life domain there were no questions about their children specifically (e.g. ‘How do you feel about your job?’ or ‘How do you feel about your physical appearance- the way you look to
others?’). Quality of life may be less intertwined with child psychopathology, but more with other factors. Alternatively, these findings can be explained by a self-selecting bias in fathers;
that is, not all fathers participated and more mothers participated then fathers. Current findings did not support our first hypothesis. However, the findings of this study are consistent with previous literature which suggests that mothers of children with disabilities have a greater potential to be affected by their child’s behavior (Jones, Totsika, Hastings & Petalas, 2013) and therefore experience lower quality of life and wellbeing than fathers (Mugno et al., 2007; Vasilopoulou & Nisbet, 2016).
In addition, even though no statistically significant differences among mothers’ quality of life in the three groups was found, in-depts explorations suggested that the presence of mother’s anxiety symptoms was a significant predictor of mothers’ quality of life.
Furthermore, the relationship dimension of family functioning was found to be marginally significant in the pooled data and significant in the data before transforming outliers and multiple imputation. In addition, anxiety symptoms were found to be marginally significant for fathers’ quality of life. However, anxiety symptoms and the relationship dimension of family functioning was found to be significant in the data before transforming outliers and multiple imputations. These results indicate the same trend of predictors (i.e., anxiety symptoms parents and family functioning) for mothers and fathers. The same trend can be confirmed with a moderate correlation between mothers- and fathers’ quality of life (r = .471) Moreover, these results suggest that factors at a parent- and family- level have more impact on their quality of life than factors at a child-level. Nevertheless, in this study the relationship of anxiety symptoms and quality of life is positive, indicating that more anxiety symptoms predict a higher quality of life. There is no previous literature supporting our finding and to prove the validity of our counterintuitive finding similar future studies are needed.
Besides anxiety symptoms in parents we found some evidence (marginal significance) that family functioning is more impaired with a lower parental quality of life (i.e., in
mothers). This is consistent with the study of Bögels and Brechman-Toussaint (2006) who found evidence for a specific relationship between maternal anxiety disorders and family dysfunction. This can also be explained with parenting stress which affects family factors such as having little time for family activities, lack of spontaneity or flexibility and stress surrounding the marital relationship (Rao & Beidel, 2009).
Limitations of this study also need to be addressed. First, the number of outliers in this dataset and therefore the results should be interpreted with caution. It was chosen to transform the values of the outliers into the highest or lowest value which was not an outlier (of its own group). Second, no sample of children with exclusively an ASD diagnosis was included, so it was not possible to investigate the individual effect of a child with an ASD diagnosis on
parental quality of life. Meaning that we could not identify if parental quality of life is
determined by the co-occurrence of an ASD and AD or exclusively an ASD. In our defense it is difficult to have a transparent group of children with an ASD only, because there is a reasonable chance of bias by overshadowing of un(der)diagnosed anxiety symptoms (Wood & Gadow, 2010). Our final limitation comprehends the definition and conceptualization of quality of life as there are many different definitions of quality of life conceptualizations across studies and the measurement of quality of life is various.
Strengths were that this study provides preliminary insights into what affects (i.e., family functioning) the quality of life of parents with children with clinical disabilities as anxiety and autism, exploring factors at the child-, parent-, and family- level. Moreover, this study is the first to investigate parental quality of life of exclusively an AD and comorbidity of AD in children with ASD. Furthermore, reports were included of both mothers and fathers of each measure. Crucially, this study proved the high quality of life among parents (i.e. fathers) with children with ASD and AD. It is important to focus more on families who successfully meet the challenge of a child with a disability, so that we may provide support to those who are struggling.
Future studies should aim to include an additional group of parents and their child exclusively diagnosed with an ASD (with no AD) and investigate if parental quality of life is determined by the co-occurrence of ASD and AD or exclusively an ASD. Moreover, this study only investigated predictors of parental quality, however it may be interesting as well to examine if the predictors are the same among the three groups. It may be that the predictors are for parental quality of life are different between parents who have a child with a clinical condition and parents with a child with no psychopathology. Additionally, it is important to further investigate the quality of life concept as integrating research to understand the effect of comorbidity on quality of life is challenging due to the many differences across studies in quality of life conceptualizations. Furthermore, future studies of quality of life in parents with psychopathology should not only investigate child factors but include parent- and family- related factors as well.
The quality of life concept may be beneficial in clinical practice at several levels (child-, parental- and family level). This study provides new valuable insights as it points out that fathers’ overall quality of life significantly decreased when having a child without a clinical condition. Moreover, anxiety symptoms in parents were found to be a predictor for parental quality of life. Improved understanding of the relationship between quality of life dysfunction in families with a child diagnosed with an ASD and/or AD may suggest new
directions to improve treatment interventions. Our findings suggest that parental- and family factors need to be considered in child treatment. Using parental quality of life can provide a sense of the wider impact of the treatment on the family. Most important, parents have a critical role in obtaining positive outcomes for their children.
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