Fibromyalgia patients should always be screened for post-traumatic stress disorder

KEYWORDS:

• Psychosomatic disorder
• pain
• chronic pain
• comorbidity
• stress

Fibromyalgia (FM) is a chronic, painful non-progressive condition with a multifactorial etiopathogenesis [1,2]. Its prevalence varies worldwide from 2 to 6% in different studies [2,3], and constitutes an important cause of social and work disabilities. It is marked by various symptoms, as generalized skeletal muscle pain, hyperalgesia, fatigue, sleep disorders, morning stiffness, and generalised tender points, in the absence of inflammatory or structural musculoskeletal abnormalities, and is frequently accompanied by anxious and depressive symptoms [1–4]. FM is often associated with stressful situations and how the patient copes with it has been cited as a fundamental factor for therapeutic response, both during its beginning and long-term course [4,5].

Some trials indicated that there is a relationship between FM and the psychosomatic symptoms of post-traumatic stress disorder (PTSD) [6,7]. PTSD is a mental disorder that may appear after a person has been exposed to a traumatic event. PTSD is defined by symptoms including re-experiencing of the traumatic moment, avoidance and numbing, and arousal. PTSD is often associated with an increased risk for several specific and non-specific somatic illnesses [8], such as cardiovascular and autoimmune disorders, physical complaints and chronic pain, including FM [5,6,9]. So, it is easy to observe that various functional somatic syndromes such as muscle pains, migraine headaches, cystitis and irritable bowel syndrome are usual in FM patients as well as in patients with PTSD [4,10].

FM can be induced by many trigger factors, as traumatic brain injury, certain infections, such as a viral illness, Lyme disease or severe emotional stress such as childhood sexual abuse (CSA) [11–13]. The prevalence of PTSD in FM patients ranges between 56% [4,11,13]. FM patients seems to have a dysregulation of the stress response capacity, with endocrine and sympathetic hyporeactivity detected under experimentally activated stress trials [6,7]. FM patients may have an increased hyperalgesic response different from the healthy control group, and this may also be linked with poor cardiovascular response [6,7]. This reactivity feature might be a link between fibromyalgia and some etiopathogenic factor, based on an allostatic capacity of the stress response system [6,7]. These hypotheses seem to indicate a high difficulty of the physiological system for an adequate response in acute stress moments, associated with the endogenous pain and inadequate response [6]. The FM patients might have a distinctive hypothalamic–pituitary–adrenocortical (HPA) dysfunction pattern that is different to other psychiatric disorders and control subjects [7]. In FM, hypersensitivity to painful or somatic stimuli due to a decrease in the nociceptive perception threshold is what would be a special feature [7]. The presence of these differences in the perception of pain may have important implications for the evaluation of these patients, so it may be essential to search the presence of PTSD in patients with FM as these patients might have a disturbed stress response system. This association might be a predictor for psychopathology, treatment strategy, and prognosis. The total difficulty of the endogenous capacity of response found in the PTSD patients seems to indicate the presence of some features within the FM patients, mainly due to the PTSD comorbidity [6,7]. Moreover, even higher rates for what concern post-traumatic stress spectrum symptoms seem to worsen the symptoms and the quality of life of FM patients [11,12]. There may be a time-based effect of PTSD on FM and perhaps more recent PTSD episodes be more powerful and compromise the prognosis [11,12]. Anyway, lifetime PTSD have also been reported to influence negatively the quality of life and severity of pain/fatigue in patients with FM [4,5].

The association between fibromyalgia and trauma was first interpreted as the possible result of a mediating factor who would act as a trigger for PTSD in people with previous trauma [14]. A prospective cohort study subsequently indicated that PTSD was a factor that could influence the psychopathological symptoms, its short and long-term treatment response and quality of life [15,16].

FM syndrome is a condition considered to represent an example of central sensitization syndrome, can be induced by different factors including PTSD due to childhood sexual abuse (CSA) [5,11]. It is estimated that 10–64% of FMS patients have history of CSA [2,5,11]. High rates of PTSD have recently been reported in FM and increasing efforts have also been oriented towards exploring the clinical relevance of not only the full-blown disorder but also of the partial or subthreshold forms that have shown to be associated with severe impairment and need for treatment as well. FM with PTSD patients usually have a history of more traumatic events, avoidance symptoms, numbing, arousal, maladaptive situations and personality features in relation to FM patients without PTSD [5,11].

Polymorphisms in dopamine associated genes as well as dysregulation of the HPA cycle leading to abnormal cortisol secretion has been indicated in both disorders [2,7]. Recent evidence suggests PTSD individuals may have biological, physiological and neuroanatomic features that could lead to structural and functional modifications in regions of the brain associated for the enduring continuous nature of the syndrome. They may terminate in structural and functional changes in affective, limbic and prefrontal brain regions such as the amygdala, insula, anterior cingulate, and prefrontal cortex. FM patients independent of any history of PTSD have a high activity in the somatosensory cortex and reduced activity in the frontal, cingulate, medial temporal, and cerebellar cortices [7,9,11]. These data seem to imply that the pain in FM may be due primarily from changes in pain processing ways.

There is no efficient agreed upon therapy for FM [2,5,11] and the treatment involves different professionals. Pharmacotherapy, aerobic exercises and cognitive behavioural therapies, consist of symptom management [2,5]. Despite PTSD and FM seems to be individually associated with significant medical load, the increased concern of having both disorders relative to either one alone cannot be underestimated. The co-occurring PTSD/FM seems to be comorbid with many other medical illnesses, compromised physical ability, or greater disability [3,5]. The time lag for developing symptoms after the trauma exposure may have consequences in the neurobiological system that increase long-term probability for developing somatic disorders, like FM, associated with PTSD [5,9].

The comorbid PTSD/FM is a frequent and clinically significant medical comorbidity in relation to each disorder alone. Many psychosocial, behavioural and biological features may serve as important features of this comorbidity [2,5]. Patients with comorbidity PTSD and FM seem to be at a high risk for cardiovascular problems due to the association of psychosocial support, behavioral (i.e., diet, drugs, physical activity), and biological features, such as inflammation, sleep pattern, and HPA function [12,13].

The role of physical and psychological trauma precipitating FM is often encountered by physicians. About PTSD, it would also be prudent to confirm that the association found in clinical trials with rating scales could be proved by research managed with special attention to clinical and psychopathological exams. Depression might be the link to the increased risk of PTSD patients to develop FM, as depression is usual in both conditions [5].

An important aspect for any the mental health team is to understand the extent the impairment of quality of life in FM may be secondary to PTSD. The clinical picture shows that the health professional must deal with in its overall complexity [5]. FM patients usually lament that their illnesses are understood by their physicians as ‘psychogenic’, and this is interpreted as of mild significance and as the patient himself has some guilty in inducing the disorder [5]. Associated to these reasons, the diagnosis of a psychiatric disorder in FM usually results in defiance by the patient as it could be understood as a proof of the psychological genesis of the illness. The large scientific data must clearly demonstrate the complexity of its origin [5], but the suffering patient must be in first place and be respected in his/her moment. FM associated with PTSD is a severe clinical situation that can have a devastating impact on an individual’s life. This association may have a significant clinical importance: the physician ought to pay attention to the right extension of this relationship and give the better approach to the patient with FM and PTSD.

A common hypothesis states that trauma and major life stressful events are not likely to cause FM or PTSD but, in genetically susceptible people, early life events, besides acute or prolonged traumatic stress in adulthood, may affect the brain modulatory circuitries of both pain and emotions responsible for the enhanced pain responses and co-occurring symptoms that are reported by patients with FM and PTSD. Potentially traumatic events, post-traumatic stress disorder, and post-traumatic stress spectrum may be present in patients with FM. Although rates of FM and PTSD vary among studies, most reported a higher proportion of this comorbidity. The clinician and the mental health team must be prepared to treat this severe comorbidity with various protocols and understand the complex etiopathogenic factors associated.

Some special recommendations should be carefully taken in to consideration by researchers and clinicians in their daily practice with patients with FM. For example, there are many mechanistic interesting studies done looking at Hypothalamic-pituitary-adrenal and autonomic function, and many neuroimaging studies, that explore the intersection of PTSD and FM [7,17].

The use of specific and easy scales for PTSD may be very useful for investigating this association [18]. The Kessler-10 and the Generalized Anxiety Disorder-7 item scale (GAD-7) are validated and useful for anxiety disorders, while the Harvard Trauma Questionnaire and Posttraumatic Diagnostic Scale are validated tools for PTSD [18] and they can be easily used in daily practice and research.

In conclusion, it is extremely helpful to better explore the screening vs the not screening and identify different treatment approaches and its influence on prognosis. Pharmacotherapy, cognitive behaviour psychotherapy, regular physical activity, mindfulness, and some new techniques as the Lumley emotional awareness therapy might be helpful [2,19] for these patients.

Declaration of interest

No potential conflict of interest was reported by the authors.