Factors associated with the persistence of medically unexplained symptoms in later life
van Driel-de Jong, Dorine
DOI:
10.33612/diss.136429372
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Publication date: 2020
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van Driel-de Jong, D. (2020). Factors associated with the persistence of medically unexplained symptoms in later life. University of Groningen. https://doi.org/10.33612/diss.136429372
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General introduction
Based on:
Diagnostiek en behandeling bij ouderen.
Driel, D. van, & Oude Voshaar, R.C. (2017).
Handboek behandeling van somatisch onvoldoende
verklaarde lichamelijke klachten (pp 263-273).
J. Spaans, J. Rosmalen, Y. van Rood, H. van der Horst,
& S. Visser (red.). Houten, Lannoo Campus.
Introduction
Medically unexplained symptoms (MUS) are defined as ‘physical symptoms that exist for more than several weeks and for which adequate medical examination has not revealed a condition that sufficiently explains the symptoms’ 1. Most MUS resolve spontaneously but in a number of cases the symptoms persist, seriously hindering patients in their daily lives. Persistent MUS are common among older persons and are associated with a lower quality of life (QoL). Their physical and mental functioning tends to be more impaired than is the case in peers with medically explained symptoms (MES) 2. The health costs for MUS are estimated to be twice as high as those for MES 3.
The reported prevalence of MUS in people over 65 years of age in the general and primary-care populations combined ranges from 4.8 to 18% 4. The large variability in reported prevalence rates of MUS in later life is, among other factors, explained by the confusion about the definitions used in the literature. Different specialisms use different terms for such symptoms, including functional somatic 5 and psychosomatic symptoms 6. In the Diagnostic Statistical Manual of Mental Disorders-IV-TR, the precursor of the DSM-5 7, MUS constituted the core criterion for the category of ‘Somatoform disorders’, which became the umbrella term for all inexplicable physical symptoms that caused significant suffering and/or limitations in the social and/or professional functioning of its sufferers. However, with the focus being shifted to the presence of positive criteria, such as disproportionate thoughts, behaviours, and emotions in relation to the physical symptoms, the DSM-5 7, implemented in the Netherlands in 2017, implied a radical change. Now classified as ‘Somatic symptom and related disorders’, it no longer mattered whether a symptom was declared ‘unexplained’, ‘insufficiently explained’ or ‘explained’. The artificial and dualistic separation between body and mind was thus abandoned 8. This new approach was deemed especially important for older patients as in later life puzzling, debilitating symptoms seldom present as exclusively unexplained physical symptoms 9. Since the research described in this thesis was initiated before the new classification of the DSM-5 was implemented in Dutch clinical practice and research, we will be using the various terms used in the literature interchangeably to describe the symptoms, including MUS.
Comorbidities in patients with MUS in later life
For a comprehensive assessment of MUS, it is crucial to understand MUS as well as any somatic and psychiatric comorbidities. There is a large positive correlation between MUS and psychiatric disorders. Charting the 12-month prevalence of common (comorbid) mental disorders in the general population, van Eck van der Sluijs and colleagues (2015) 10 indeed found comorbidity to be higher in patients reporting MUS (13.5% for mood disorders and 19% for anxiety disorders) than in peers with explained symptoms (7.4% and 13.3% respectively). In general practice, there is an overlap between somatoform disorders and anxiety and/or depressive disorders, with a weighted prevalence of 26% being reported 11. In tertiary care, even 49% of 340 patients with somatoform disorders was also diagnosed with a mood disorder, 62%
with an anxiety disorder, and 51% with a personality disorder 12.
Also in older patients with MUS (age range: 60-92 years) psychiatric comorbidity is high. In a pilot study of 32 older adults (mean age: 75 years) with confirmed MUS at our specialised mental-health centre, 69% were found to have a comorbid psychiatric disorder, with 56% suffering from depression, 31% from an anxiety disorder, and 19% from a substance use disorder 13. There is also evidence that psychiatric comorbidity complicates treatment and reduces the likelihood of recovery 14-16.
The difficulty in older patients suspected of MUS centres around the issue whether the reported physical symptoms can be shown to be medically founded or not. But when do medical experts reach the decision that there is no known condition that sufficiently explains the symptoms? Doctors are often hesitant to diagnose MUS out of fear of overlooking an underlying somatic disease. A systematic review and meta-analysis showed that in diagnostic evaluation studies 8.8% of MUS diagnoses were later revised and 0.5% in follow-up studies 17. But what does this mean for the older patient presenting with MUS when we consider that as people grow older, the number of physical diseases increases? 18. In another pilot study, we found a medical explanation for the symptoms in three (8.1%) of the 37 older patients originally referred with suspected MUS 9. Moreover, a comprehensive geriatric assessment revealed that in half of the patients with MUS their physical symptoms could still be partially explained by a known somatic condition, again emphasising that in older adults the distinction between explained and unexplained symptoms is complicated. The section on somatic symptom disorders in the DSM-5 offers a starting point for the classification of ‘unexplained’ or ‘partly unexplained’ syndromes, where the definitive diagnosis should focus on maladaptive cognitions, emotions, or behaviours related to a physical symptom, irrespective of whether that symptom can be medically explained or not. This change in the DSM classification may then support clinicians in their diagnosis and treatment of older persons presenting with MUS.
Older patients with MUS: professionals’ perspective
MUS and patients with MUS are often labelled as ‘difficult’, with professionals using the adjective to describe their often emotional experiences with diagnosing, explaining, communicating about, and managing the great variety of conditions in this population. Structural shortcomings in the healthcare system and the conceptual basis for MUS were other factors they frequently cited that could hamper them in their ability to provide the best possible care 19. Although not yet specifically studied, this is likely to be no different for older patients with MUS. In general, therapists have little interest in this older patient group 20. Also in research, the older age group is often ignored 21-24. Koenig, among others, concluded that professionals have certain (pre) judgments with regard to the therapeutic possibilities for change in this population 25. In conclusion, there are two main reasons why the care for older patients with MUS is suboptimal. Many health professionals find their health problems difficult to manage, while their more advanced age is deemed to limit therapeutic options. As a result, many of these older patients remain deprived of an adequate diagnosis and fitting, evidence-based treatment.Factors associated with the persistence of MUS in later life
Since MUS in older adults is associated with (seriously) impaired QoL, high comorbidity of psychiatric disorders, and a bias of health professionals towards this patient group, there is an urgent need for both the patient and the therapist to better understand MUS and regain control over the symptoms. For this reason, a number of models have been formulated to explain the development and maintenance of MUS 26, 27, all building on the biopsychosocial model that assumes that biological, psychological, and social factors play a role in every disorder 28. One such model is the cognitive-behavioural model of MUS 29, 30 where the fundamental assumption is that symptoms are maintained by “a self-perpetuating, multifactorial cycle encompassing cognitive, behavioural and physiological factors”. The model makes a distinction between predisposing, precipitating, and perpetuating factors. Since it is presumed that predisposing and precipitating factors are often difficult to change 31-35, it is deemed more useful to focus on biological, psychological, and social factors associated with the persistence of the symptoms 29, 36. The key mechanism in the cognitive behavioural model is based on the premise that the individual factors become locked in a vicious cycle that thus maintains the symptom(s). Psychological distress and psychiatric comorbidity are such factors implicated in the persistence of MUS. Also, the personal meanings patients give to somatic symptoms may help maintain them 37. The way people think about their illness impacts their health-related QoL and way of living 38, with maladaptive cognitions being important contributors to the persistence of MUS 29.
Cognitive-behavioural therapy (CBT) aimed at reducing the disease burden of MUS accordingly focuses on the individual factors associated with the potential origin and continuation of the symptoms and has proven effective in adults up to 65 years 39-41. Although the research into CBT protocols targeting older patients with MUS is limited to uncontrolled studies, the results show their feasibility 42, 43. After completing their treatment, the patients reported less psychological distress and improved Qol. In the Older Persons with Unexplained Symptoms (OPUS) study, in-depth interviews with the participants after a group CBT intervention were conducted to gain insight into their personal experiences with the treatment and its outcome. More than half of the interviewees reported notable amelioration of their symptoms and improvement in their daily functioning. However, the number of patients who were willing to attend the CBT sessions was relatively small, which was partly due to their limited mobility, with some participants reporting to have been prevented from attending due to physical discomfort or problems travelling to and from the treatment centre. Given these obstacles, we became interested in the potential of ‘treatment-at-home’ formats such as e-health for older patients with MUS.
A case description (part 1)
John (pseudonym) is a 79-year-old man who has repeatedly visited his GP and various specialists (internist, pulmonologist, orthopaedist, pain specialist) for a specific complaint but to no avail. He complains his right shoulder feels “bad”. He does not feel any pain but insists the shoulder just does not feel right at all. He also complains of fatigue and a shortness of breath (“lack of air”). John suffers from COPD but claims he is much less bothered by this than by the bad shoulder, which controls his life. He wants to do everything to get rid of the distressing sensation and is willing to see any doctor who could possibly relieve him from it. He has asked his GP for help multiple times, saying: “This is no way to live your life; I sometimes want this life to end. I plead you to help me get rid of this awful feeling in my shoulder”. John eventually stopped seeing his GP because “he does not know what to do with my complaints”. He has also not been to see his relatives for a long time because of his physical limitations. With this bad shoulder, he prefers to stay home. His wife and children understand his plight and decisions, especially since because of his COPD he has “little air”. His granddaughter now comes to visit them to celebrate her birthday with her grandfather.
John’s cognitions are mainly about helplessness. He misses the things he used to love doing and often feels helpless and useless. He does not go out much and mostly sits in his chair, pressing his shoulder up against the back of the chair to “push away the bad feeling”. His overall condition is deteriorating and he needs increasingly more oxygen. In view of this exacerbation of his COPD symptoms, his GP decides to admit him to hospital to have this seen to.
In the absence of any medical explanation of the reported shoulder symptoms, the case description above prompts various questions:
- How do we explore the possibility of MUS?
- Are there any indications of psychiatric comorbidity?
- Are there evident factors that help perpetuate the shoulder symptoms? - Does John have any maladaptive illness cognitions?
- How can we help improve John’s daily functioning? - How can we help improve John’s quality of life?
Aims and outline of this thesis
Especially in the care for older adults with medically unexplained symptoms (MUS) there is still much to be improved. As a first step towards the development and implementation of tailored evidence-based CBT, we need to understand the underlying mechanisms of the maintenance of factors associated with the persistence of MUS in this population. The overall aim of the studies reported in this thesis then is to expand our knowledge of the factors
associated with the persistence of MUS and inform CBT as an approach for older patients, with the following three fundamental questions guiding the research:
1. How can we assess MUS in later life (Chapter 2)?
2. Which factors are associated with the persistence of MUS in older patients (Chapters 3, 4,
5, and 6)?
3. What is the feasibility of internet-based CBT for older patients with MUS (Chapters 7 and 8)? 1. How can we assess MUS in later life?
Assessment of somatization and medically unexplained symptoms in later life (Chapter 2)
In this systematic review of the literature, current questionnaires for MUS (n=46) are evaluated for their usability in older age groups.
2. Which factors are associated with the persistence of MUS in older patients?
Psychiatric characteristics of older persons with medically unexplained symptoms; a comparison with older patients suffering from medically explained symptoms (Chapter 3)
The OPUS (Older Persons with medically Unexplained Symptoms) study was designed as a case-control study and included a total of 272 older patients reporting or diagnosed with physical symptoms and/or diseases, with 118 cases suffering from MUS and 154 controls from MES. The main objective of the OPUS study was to examine clinical and care characteristics, as well as the consequences of late-life MUS.
Since psychiatric comorbidity generally affects the treatment outcome of the primary somatic symptom under study, we decided to start by describing psychiatric comorbidities among patients with late-life MUS and compare their prevalence to those recorded for older patients with MES. Based on an earlier pilot study in which 69% of 32 older patients with MUS had a comorbid affective, anxiety disorder 13, we expected significantly higher rates of mood, anxiety, and substance use disorders in the MUS group.
Perpetuating factors of medically unexplained symptoms in specialized care: a comparison of three age groups and both sexes (Chapter 4)
In Chapter 4 we report on the interviews we conducted with 160 patients with MUS to explore whether the biological, behavioural, cognitive, emotional, and social factors assumed to be contributed to the persistence of MUS differ by age and sex.
Illness cognitions in later life: development and validation of the extended illness cognition questionnaire (ICQ-plus) (Chapter 5)
Maladaptive illness cognitions, i.e. dysfunctional thoughts people have about their disease, may obstruct recovery. In Chapter 5 we describe the development of the Illness Cognition Questionnaire-plus, (ICQ-plus), extending the ICQ to also take into account the illness cognitions of older patients with MUS. In a case control study in 240 patients it is investigated whether the illness cognitions of older patients with MUS and MES differ.
Illness cognitions in older patients with physical symptoms: natural course and determinants of change (Chapter 6)
Being ill is a personal experience, with sensations, emotions, and perceptions differing among persons with the same diseases, while illness cognitions may also change during the course of an illness. Knowledge about the natural course of patients’ cognitions and the factors influencing their change over time may provide a better insight into the persistence or amelioration of physical symptoms in older patients. Chapter 6 comprises a cohort study in which the natural course of illness cognitions and the determinants of change over time are charted in 154 patients with late-life MUS and/or MES.
3. Feasibility of internet-based CBT for older patients with MUS
The role of age, education, and digital health literacy in usability of internet-based Cognitive Behavioural Therapy for chronic pain: mixed methods study (Chapter 7)
E-health interventions might be a cost-effective strategy to deliver treatment targeting perpetuating factors of MUS. Using a mixed method design, in the study presented in
Chapter 7, we explore the usability of ‘Master Your Pain’, a dedicated Dutch-language iCBT
for chronic pain that we derived from an evidence-based iCBT platform for chronic conditions. We adapted six modules from the original treatment modules that now specifically focus on coping with chronic pain. We additionally examined the relationship between its usability outcomes and the factors age, educational level, and digital-health literacy skills in 32 psychiatric patients (aged 22-75 years).
Feasibility of an internet-based Cognitive Behavioural Therapy for older treatment-seeking patients
(Chapter 8)
Although computer and Internet use steadily increases among older persons, it remains unknown whether older treatment-seeking patients in specialized care are motivated for and able to use iCBT. In Chapter 8, we examine what older treatment-seeking patients think about e-health treatments (n=52) using a specially designed questionnaire. By means of interviews and observations we subsequently gauge which problems they encounter during iCBT (n=10). Lastly, in Chapter 9 the findings of the combined studies are summarised, discussed and put into context, with implications and recommendations for clinical (mental-health) care and future research concluding the thesis.
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