The concept of affective spectrum disorder: relationship to fibromyalgia and other syndromes of chronic fatigue and chronic muscle pain

Contribution of central sensitization to stress-induced spreading hyperalgesia in rats with orofacial inflammation

Temporomandibular disorder (TMD) is commonly comorbid with fibromyalgia syndrome (FMS). The incidence of these pain conditions is prevalent in women and prone to mental stress. Chronic pain symptoms in patients with FMS and myofascial TMD (mTMD) are severe and debilitating. In the present study, we developed a new animal model to mimic the comorbidity of TMD and FMS. In ovariectomized female rats, repeated forced swim (FS) stress induced mechanical allodynia and thermal hyperalgesia in the hindpaws of the 17β-estradiol (E2) treated rats with orofacial inflammation. Subcutaneous injection of E2, injection of complete Freund’s adjuvant (CFA) into masseter muscles or FS alone did not induce somatic hyperalgesia. We also found that the somatic hyperalgesia was accompanied by upregulation of GluN1 receptor and serotonin (5-hydroxytryptamine, 5-HT)_3A receptor expression in the dorsal horn of spinal cord at L4-L5 segments. Intrathecal injection of N-methyl-D-aspartic acid receptor (NMDAR) antagonist 2-amino-5-phosphonovaleric acid (APV) or 5-HT₃ receptor antagonist Y-25130 blocked stress-induced wide-spreading hyperalgesia. These results suggest that NMDAR-dependent central sensitization in the spinal dorsal horn and 5-HT-dependent descending facilitation contribute to the development of wide-spreading hyperalgesia in this comorbid pain model.

The ALPIM (Anxiety, Laxity, Pain, Immune, and Mood) Syndrome in Adolescents and Young Adults: A Cohort Study

OBJECTIVE

ALPIM (anxiety, laxity, pain, immune, and mood) syndrome has been previously described in adults. The authors aimed to identify its occurrence in adolescents and confirm its existence in adults. Given the association of the disorder with somatic symptoms, separation anxiety disorder (SAD) was explored as an ALPIM comorbidity.

METHODS

Medical records of patients aged 11-34 with a diagnosis of depression or anxiety (panic disorder, SAD, social anxiety or generalized anxiety disorder) seen during a 1-year period were reviewed. Data were collected on the presence of ALPIM comorbidities. Analyses were conducted to detect their co-occurrence and evaluate possible predictors of the ALPIM syndrome.

RESULTS

Inclusion criteria were met by 185 patient charts. A significant association was observed between the ALPIM comorbidities with 20 study subjects (10.8%) meeting criteria for ALPIM syndrome (patients with one or more diagnoses from each ALPIM domain). Patients with SAD had increased odds of being diagnosed with ALPIM (odds ratio=7.14, 95% CI=2.48-20.54, p<0.001). Neither major depression nor generalized anxiety disorder was found to be predictive of ALPIM syndrome. There was no difference in the prevalence of ALPIM-related comorbidities between study subjects <18 years old compared with those ≥18 years old.

CONCLUSIONS

These findings reestablish the association of distinct psychiatric and nonpsychiatric conditions described as the ALPIM syndrome. Furthermore, the syndrome may present during adolescence. SAD may be an independent predictive factor for the occurrence of ALPIM syndrome. Patients with individual ALPIM comorbidities should be assessed for the syndrome, especially if they have a history of SAD.

A Subgroup of Chronic Low Back Pain Patients With Central Sensitization

BACKGROUND

Our knowledge of central sensitization (CS) in chronic low back pain (CLBP) is limited. 2011 fibromyalgia criteria and severity scales (2011 FM survey) have been used to determine FM positive as a surrogate of CS. The major features of CS including widespread hyperalgesia and dysfunction of the descending inhibitory pathways can be identified by pressure pain threshold (PPT) and conditioned pain modulation (CPM) tests. The purpose of the study was to examine neurophysiological characteristics and psychosocial symptoms in a subgroup of FM-positive CLBP compared with FM-negative CLBP patients.

METHODS

A total of 46 participants with CLBP and 22 pain-free controls completed outcome measures of the 2011 FM survey, PPT and CPM tests, and psychosocial questionnaires. Differences between FM-positive and FM-negative CLBP participants on these measures and correlations were analyzed.

RESULTS

The 2011 FM survey identified 22 (48%) participants with CLBP as FM positive. FM-positive CLBP participants showed lower PPT values of the thumbnail (P=0.011) and lower back (P=0.003), lower CPM values of the thumbnail (P=0.002), and more severe pain catastrophizing, anxiety, and depression symptoms (P<0.05) than FM-negative CLBP participants. The 2011 FM scores were significantly correlated with the PPT and CPM values of the thumbnail and with psychosocial symptoms (P<0.001).

DISCUSSION

Our findings suggest a subgroup of CLBP patients exhibiting with signs and symptoms of CS. Associations between subjective and objective CS measures indicate that the 2011 FM survey can be utilized to identify the presence of CS in CLBP in clinical practice.

Obstructive sleep apnea co-morbidity in patients with fibromyalgia: a single-center retrospective analysis and literature review

Background: Fibromyalgia (FM) is a chronic medical condition characterized by widespread pain, sleep disturbance, and cognitive dysfunction. Sleep disorders are thought to play a prominent role in the etiology and symptomatic management of FM, specifically obstructive sleep apnea (OSA). In order to provide collaborative care, we need a better understanding of any overlapping presentation of FM and OSA. We conducted a site-wide review of patients from 2012-2016 to identify FM patients diagnosed with OSA. Methods: Charts were reviewed in patients aged 18 and above from 2012-2016 using ICD codes from a clinical data repository. Intersection of patients with a diagnosis of FM and OSA in clinics of psychiatry, sleep, rheumatology, and other outpatient clinics was compared. Polysomnography order patterns for FM patients were investigated. Results: Co-morbidity was highest in the sleep clinic (85.8%) compared to psychiatry (42.0%), rheumatology (18.7%), and other outpatient clinics (3.6%) (p<0.001). In the rheumatology and other outpatient clinics, 93.5% and 96% of patients respectively, had no polysomnography ordered. Pairwise comparison of co-morbidity in clinics: sleep vs psychiatry, sleep vs rheumatology, sleep vs other clinics, psychiatry vs rheumatology, psychiatry vs other clinics, and rheumatology vs other clinics were statistically significant after applying a Sidak adjustment to the p-values (all p<0.001). Conclusion: Our analysis suggests that there could be a correlation between FM and OSA, and referral to sleep studies is recommended in the management of patients with FM. The varying prevalence of FM patients with co-morbid OSA in sleep clinics when compared to other outpatient clinics suggests a discrepancy in the identification of FM patients with OSA. When properly screened, OSA co-morbidity has the potential to be higher in other outpatient clinics.

Prevalence of depressive disorder among patients with fibromyalgia: Systematic review and meta-analysis

BACKGROUND

It is acknowledged that fibromyalgia (FM) as a medical (rheumatological) disorder and major depressive disorder (MDD) as a mental disorder often co-occurs, but the inconsistency is prevailing at study-level and no overall estimate of the co-occurrence exist.

AIMS

This systematic review and meta-analysis aimed to estimate the overall point- and life-time prevalence of MDD among FM patients based on structured clinical interviews (SCI); and to estimate the point-prevalence of MDD among FM patients based on screening symptom scales (SSS).

METHOD

The electronical databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and PsycINFO were searched for papers that reported on prevalence of MDD among FM patients. Eligible studies were included in a random effects meta-analysis pooling the prevalence of depression.

RESULTS

The literature search identified 11 eligible studies for the meta-analysis. For SCI, the overall pooled point-prevalence (PP) was 25% (95% CI 19 to 31%), and life-time prevalence (LP) was 65% (95% CI 59 to 71%). When estimating the PP with self-administered SSS the overall pooled PP was 45% (95% CI 32 to 59%), and a single clinician-administered SSS yielded a PP of 23% (95% CI 10 to 41%). There was low inconsistency for the SCI and high inconsistency for the SSS.

CONCLUSION

One fourth of all FM patients had MDD, and more than half experienced MDD during their life-time according to clinician-administered instruments. Prevalence of MDD was almost twice as high when using self-administered symptom scales and may be likely to overestimate the co-occurrence.

Association Between Predeployment Optimism and Onset of Postdeployment Pain in US Army Soldiers

IMPORTANCE

Pain after deployment is a major health care concern. While risk factors have been previously studied, few studies have explored protective factors.

OBJECTIVE

To examine the prospective association between predeployment optimism and the onset of new pain after deployment in US Army soldiers.

DESIGN, SETTING, AND PARTICIPANTS

This prospective longitudinal cohort study examined US Army soldiers (active duty, Reserve, and National Guard) who deployed to Afghanistan or Iraq between February 12, 2010, and August 29, 2014, and completed the necessary psychological and health assessments before and after deployment. Analyses were performed in the Person-Event Data Environment between July 2016 and November 2018. This study relied exclusively on existing, secondary Army data. Of the 413 763 Army soldiers who met the specified deployment criteria, 385 925 soldiers were missing 1 or more of the required assessment forms. Of the remaining 27 838 soldiers who were examined for eligibility, 7104 soldiers were excluded because of preexisting back pain, joint pain, or frequent headaches. These exclusions resulted in a final analytic sample of 20 734 eligible soldiers.

MAIN OUTCOMES AND MEASURES

This study examined new reports of pain after deployment, including new back pain, joint pain, and frequent headaches.

RESULTS

Among 20 734 US Army soldiers (87.8% male; mean [SD] age, 29.06 [8.42] years), 37.3% reported pain in at least 1 new area of the body after deployment: 25.3% reported new back pain, 23.1% reported new joint pain, and 12.1% reported new frequent headaches. As a continuous measure, each 1-U increase in optimism was associated with 11% lower odds of reporting any new pain after deployment, even while adjusting for demographic, military, and combat factors (odds ratio, 0.89; 95% CI, 0.86-0.93). Tertile analyses revealed that compared with soldiers with high optimism (lowest odds of new pain) soldiers with low optimism had 35% greater odds of reporting new pain in any of the 3 sites evaluated (odds ratio, 1.35; 95% CI, 1.21-1.50). In addition, a larger increase in risk of new pain was observed when comparing the moderate-optimism and low-optimism groups rather than the high-optimism and moderate-optimism groups.

CONCLUSIONS AND RELEVANCE

Higher levels of optimism were associated with lower odds of reporting new pain after deployment, over and above other common determinants of pain, including demographic and military characteristics and combat experiences. Soldiers with low levels of optimism before deployment could benefit from programs geared toward enhancing optimism.

Facts and myths pertaining to fibromyalgia

Fibromyalgia (FM) is characterized by chronic widespread pain, unrefreshing sleep, physical exhaustion, and cognitive difficulties. It occurs in all populations throughout the world, with prevalence between 2% and 4% in general populations. Definition, pathogenesis, diagnosis, and treatment of FM remain points of contention, with some even contesting its existence. The various classification systems according to pain medicine, psychiatry, and neurology (pain disease; persistent somatoform pain disorder; masked depression; somatic symptom disorder; small fiber neuropathy; brain disease) mostly capture only some components of this complex and heterogeneous disorder. The diagnosis can be established in most cases by a general practitioner when the symptoms meet recognized criteria and a somatic disease sufficiently explaining the symptoms is excluded. Evidence-based interdisciplinary guidelines give a strong recommendation for aerobic exercise and cognitive behavioral therapies. Drug therapy is not mandatory. Only a minority of patients experience substantial symptom relief with duloxetine, milnacipran, and pregabalin.

Addressing Opioid-Related Chemical Coping in Long-Term Opioid Therapy for Chronic Noncancer Pain: A Multicenter, Observational, Cross-Sectional Study

Opioid consumption has increased worldwide, which carries the risk of opioid use disorder (OUD). However, the literature on OUD and opioid-related chemical coping (OrCC) in chronic noncancer pain (CNCP) is heterogeneous, with most studies conducted in the United States. We performed a multicenter, observational, cross-sectional study to address OrCC in long-term opioid therapy (LtOT) for CNCP in South Korea. The objectives were to determine the frequency and predictors of OrCC. We included 258 patients. Among them, fifty-five (21%) patients showed OrCC. The sample had high pain catastrophizing (≥30 points; 66%), moderate-severe insomnia (≥15 points; 63%), low resilience (68 points), and high suicidal ideation (67%). OrCC patients had greater pain interference (85.18% vs. 58.28%, p = 0.017) and lower satisfaction with the LtOT (56.4% vs. 78.3%, p = 0.002). In multivariable analysis, alcohol abuse (OR = 6.84, p = 0.001), prescription drugs abuse (OR = 19.32, p = 0.016), functional pain (OR = 12.96, p < 0.001), head and neck pain (OR = 2.48, p = 0.039), MEDD (morphine equivalent daily dose) ≥ 200 mg/day (OR = 3.48, p = 0.006), and ongoing litigation (OR = 2.33, p = 0.047) were significant predictors of OrCC. In conclusion, the break-out of OrCC in CNCP in South Korea was comparable to those in countries with high opioid consumption, such as the United States, regardless of the country's opioid consumption rate.

Psychiatry and Pain Management: at the Intersection of Chronic Pain and Mental Health

PURPOSE OF REVIEW

Chronic pain impacts millions of people in the USA. At the heart of the problem of chronic pain remains the complex psychosocial aspects associated with living with chronic pain. Given the overlap between chronic pain and mental health, a promising treatment approach is to improve how we integrate psychiatry into pain management.

RECENT FINDINGS

Treatment of chronic pain and comorbid mental health issues requires a multidisciplinary approach. Advancements in how pain is understood, especially centralized pain, have helped inform both pharmacological and behavioral interventions for pain. Given the growing concerns about the opioid epidemic and the lack of data supporting the use of opioids for long-term pain management, new treatment approaches are needed. Psychiatrist may be uniquely suited to help address comorbid mental health disorders and addiction in the context of chronic pain management. Addressing the psychiatric needs of chronic pain patients remains challenging and there is much room to improve how we address the complex issues associated with living with chronic pain. We believe psychiatrists are an important piece of the pain management puzzle.

Controversies and challenges in fibromyalgia: a review and a proposal

Fibromyalgia (FM) is the most commonly encountered chronic widespread pain (CWP) condition in rheumatology. In comparison to inflammatory arthritis (IA), it can seem ill defined with no clear understanding of the pathology and therefore no specific targeted treatment. This inevitably raises controversies and challenges. However, this is an outdated view perpetuated by poor teaching of pain at undergraduate and postgraduate levels, and the perennial problem of advances in relevant cross-speciality knowledge penetrating speciality silos. Research has provided a better understanding of the aetiopathology and FM is now regarded as a centralized pain state. Effective treatment is possible utilizing a multidisciplinary approach combining nonpharmacologic and pharmacologic treatments rooted in a biopsychosocial model. This article will provide a review of the mechanisms, diagnosis and treatment of FM, focus on some ongoing contentious issues and propose a change to the diagnostic terminology.

Depressive Disorder, Anxiety Disorder and Chronic Pain: Multiple Manifestations of a Common Clinical and Pathophysiological Core

INTRODUCTION

A high proportion of depressive disorders are accompanied by anxious manifestations, just as depression and anxiety often present with many painful manifestations, or conversely, painful manifestations cause or worsen depressive and anxious expressions. There is increasingly more evidence of the pathophysiological, and neurophysiological and technical imaging similarity of pain and depression.

METHODS

Narrative review of the pathophysiological and clinical aspects of depression and chronic pain comorbidity. Research articles are included that emphasise the most relevant elements related to understanding the pathophysiology of both manifestations.

RESULTS

The pathological origin, physiology and clinical approach to these disorders have been more clearly established with the latest advances in biochemical and cellular techniques, as well as the advent of imaging technologies. This information is systematised with comprehensive images and clinical pictures.

CONCLUSIONS

The recognition that the polymorphism of inflammation-related genes generates susceptibility to depressive manifestations and may modify the response to antidepressant treatments establishes that the inflammatory response is not only an aetiopathogenic component of pain, but also of stress and depression. Likewise, the similarity in approach with images corroborates not only the structural, but the functional and pathophysiological analogy between depression and chronic pain. Knowledge of depression-anxiety-chronic pain comorbidity is essential in the search for effective therapeutic interventions.

The impact of depressive and bipolar symptoms on socioeconomic status, core symptoms, function and severity of fibromyalgia

AIM

To evaluate the prevalence of depressive and bipolar symptoms in a cohort of consecutive fibromyalgia (FM) patients seen in a tertiary care center and to determine the relationship between depressive and manic symptoms with FM symptoms, socioeconomic status, severity and function.

METHODS

Three hundred and five FM patients were enrolled; demographic, clinical and questionnaire data were collected. Depressive symptoms were measured by the Patient Health Questionnaire (PHQ-9), manic symptoms by the Mood Disorders Questionnaire (MDQ).

RESULTS

The FM cohort had the following characteristics: age 43.53 (11.7) years; 86.5% white; 82.7% female; PHQ-9 ≥ 10, 59.7%, mean 11.9 (7.3); no depression 11.4%, mild 29.1%, moderate 27.5%, moderate severe 17.7%, severe 14%; anxiety 41.6%; 21.3% had either an MDQ score ≥ 7 and/or reported a past diagnosis of bipolar disorder (BD). Increasing levels of depression severity, as well as a positive screen for BD were significantly associated with increasing prevalence and severity of FM symptoms, longer duration of morning stiffness, and increased severity of FM. Increasing levels of depression were significantly associated with increase in prevalence of reported past sexual abuse, and a decline in socioeconomic status, including higher disability and unemployment rates.

CONCLUSION

Patients with severe FM disease activity, high load of symptoms, prolonged morning stiffness, increased disability, lower socioeconomic status and those who take a lot of medications for FM should be evaluated for depressive and manic symptoms.

The Iceberg Nature of Fibromyalgia Burden: The Clinical and Economic Aspects

This review has focused on important but less visible aspects of fibromyalgia (FM) with respect to the high impact of this disorder on patients and societies. FM is a common but challengeable illness. It is characterized by chronic widespread pain, which can be accompanied by other symptoms including fatigue, sleep disturbances, cognitive dysfunction, anxiety and depressive episodes. While our understanding of this debilitating disorder is limited, diagnosis and treatment of this condition is very difficult, even in the hands of experts. Due to the nature of disease, where patients experience invalidation by medical services, their families and societies regarding the recognition and management of disease, direct, indirect and immeasurable costs are considerable. These clinical and economic costs are comparable with other common diseases, such as diabetes, hypertension and osteoarthritis, but the latter usually receives much more attention from healthcare and non-healthcare resources. Present alarming data shows the grave and "iceberg-like" burden of FM despite the benign appearance of this disorder and highlights the urgent need both for greater awareness of the disease among medical services and societies, as well as for more research focused on easily used diagnostic methods and target specific treatment.

Diagnosing and treating chronic musculoskeletal pain based on the underlying mechanism(s)

Until recently, most clinicians considered chronic pain to be typically due to ongoing peripheral nociceptive input (i.e., damage or inflammation) in the region of the body where the individual is experiencing pain. Clinicians are generally aware of a few types of pain (e.g., headache and phantom limb pain) where chronic pain is not due to such causes, but most do not realize there is not a single chronic pain state where any radiographic, surgical, or pathological description of peripheral nociceptive damage has been reproducibly shown to be related to the presence or severity of pain. The primary reason for this appears to be that both the peripheral and central nervous systems play a critical role in determining which nociceptive input being detected by sensory nerves in the peripheral tissues will lead to the perception of pain in humans. This manuscript reviews some of the latest findings regarding the neural processing of pain, with a special focus on how clinicians can use information gleaned from the history and physical examination to assess which mechanisms are most likely to be responsible for pain in a given individual, and tailors therapy appropriately. A critical construct is that, within any specific diagnostic category (e.g., fibromyalgia (FM), osteoarthritis (OA), and chronic low back pain (CLBP) are specifically reviewed), individual patients may have markedly different peripheral/nociceptive and neural contributions to their pain. Thus, just as low back pain has long been acknowledged to have multiple potential mechanisms, so also is this true of all chronic pain states, wherein some individuals will have pain primarily due to peripheral nociceptive input, whereas in others peripheral (e.g., peripheral sensitization) or central nervous system factors ("central sensitization" or "centralization" of pain via augmented pain processing in spinal and brain) may be playing an equally or even more prominent role in their pain and other symptoms.

Mood and Anxiety Disorders in Chronic Fatigue Syndrome, Fibromyalgia, and Irritable Bowel Syndrome: Results From the LifeLines Cohort Study

OBJECTIVE

Functional somatic syndromes (FSSs) have often been linked to psychopathology. The aim of the current study was to compare prevalence rates of psychiatric disorders among individuals with chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS).

METHODS

This study was conducted in 94,516 participants (mean [standard deviation] age = 44.6 [12.5] years, 58.7% women) of the general-population cohort LifeLines. FSSs were assessed by self-reports. Mood disorders (i.e., major depressive disorder and dysthymia) and anxiety disorders (i.e., generalized anxiety disorder, social phobia, panic disorder with/without agoraphobia, and agoraphobia) were assessed by means of the Mini International Neuropsychiatric Interview. Risks on psychiatric disorders were compared for individuals with CFS, FM, and IBS by using logistic regression analyses adjusted for age and sex.

RESULTS

Prevalence rates of CFS, FM, and IBS were 1.3%, 3.0%, and 9.7%, respectively. Individuals with CFS, FM, and IBS had significantly more mood (odds ratios [ORs] = 1.72-5.42) and anxiety disorders (ORs = 1.52-3.96) than did individuals without FSSs, but prevalence rates were low (1.6%-28.6%). Individuals with CFS more often had mood (ORs = 2.00-4.08) and anxiety disorders (ORs = 1.63-2.32) than did individuals with FM and IBS. Major depressive disorder was more common in FM than in IBS (OR = 1.58, 95% confidence interval = 1.24-2.01), whereas these groups did not differ on dysthymia or anxiety disorders.

CONCLUSIONS

Mood and anxiety disorders are more prevalent in individuals with FSSs, and particularly CFS, than in individuals without FSSs. However, most individuals with FSSs do not have mood or anxiety disorders.

Fibromyalgia and related conditions

Fibromyalgia is the currently preferred term for widespread musculoskeletal pain, typically accompanied by other symptoms such as fatigue, memory problems, and sleep and mood disturbances, for which no alternative cause can be identified. Earlier there was some doubt about whether there was an "organic basis" for these related conditions, but today there is irrefutable evidence from brain imaging and other techniques that this condition has strong biological underpinnings, even though psychological, social, and behavioral factors clearly play prominent roles in some patients. The pathophysiological hallmark is a sensitized or hyperactive central nervous system that leads to an increased volume control or gain on pain and sensory processing. This condition can occur in isolation, but more often it co-occurs with other conditions now being shown to have a similar underlying pathophysiology (eg, irritable bowel syndrome, interstitial cystitis, and tension headache) or as a comorbidity in individuals with diseases characterized by ongoing peripheral damage or inflammation (eg, autoimmune disorders and osteoarthritis). In the latter instance, the term centralized pain connotes the fact that in addition to the pain that might be caused by peripheral factors, there is superimposed pain augmentation occurring in the central nervous system. It is important to recognize this phenomenon (regardless of what term is used to describe it) because individuals with centralized pain do not respond nearly as well to treatments that work well for peripheral pain (surgery and opioids) and preferentially respond to centrally acting analgesics and nonpharmacological therapies.

Shared genetic factors underlie chronic pain syndromes

Chronic pain syndromes (CPS) are highly prevalent in the general population, and increasingly the evidence points to a common etiological pathway. Using a large cohort of twins (n=8564) characterized for chronic widespread musculoskeletal pain (CWP), chronic pelvic pain (PP), migraine (MIG), dry eye disease, and irritable bowel syndrome (IBS), we explored the underlying genetic and environmental factors contributing to CPS and the correlation between them. The sample was predominantly female (87.3%), with a mean age of 54.7 (±14.7) years. Prevalence of the different CPS ranged from 7.4% (PP) to 15.7% (MIG). For all CPS the within-twin correlation in monozygotic twin pairs was higher than in dizygotic pairs, suggesting a heritable component. Estimated heritability ranged from 19% (IBS) to 46% (PP). Except for MIG, we found significant pairwise phenotypic correlations between the CPS. The phenotypic correlation was highest between CWP and IBS (0.40; 95% confidence interval: 0.27 to 0.46). Excluding MIG from further analyses, cross-twin cross-trait correlations were higher in monozygotic compared with dizygotic twin pairs, suggestive of shared genetic factors between CWP, PP, IBS, and dry eye disease. Twin modeling analysis revealed the common pathway model as the model best explaining the observed pattern of correlation between the traits, with an estimated heritability of 66% of the underlying latent variable. These results are evidence of shared genetic factors in conditions manifesting chronic pain and justify the search for underlying genetic variants.

Before the onset of interstitial cystitis/bladder pain syndrome, the presence of multiple non-bladder syndromes is strongly associated with a history of multiple surgeries

OBJECTIVE

Certain functional somatic syndromes (FSSs) such as fibromyalgia and irritable bowel syndrome are accompanied by diffuse pain amplification. Women with interstitial cystitis/bladder pain syndrome (IC/BPS) have numerous FSSs, as well as other non-bladder syndromes (NBSs) that are linked to the FSSs. They also report multiple surgeries. Since pain is a common indication for surgery, we tested the hypothesis that NBSs were associated with surgeries.

METHODS

We interviewed 312 incident IC/BPS cases and controls on NBSs and number of surgeries before the index date (for cases, IC/BPS onset date). Poisson and logistic regression analyses adjusted for age, race, educational level, and menopause.

RESULTS

Number of surgeries increased with number of NBSs in both cases and controls whether chronic pelvic pain (CPP), the only NBS generally accepted as an indication for surgery, was present or not. Logistic regression analysis showed that among cases CPP was the only individual NBS associated with a history of multiple surgeries, and then only modestly [odds ratio (OR) 1.9, confidence intervals (CI) 1.06, 3.2]. By far the strongest association was the number of NBSs. The OR for multiple surgeries increased with number of NBSs: for cases with 4-5 NBSs the OR was 14.1 (1.8, 113) and with 6-9 NBSs, 33.1 (3.9, 279). Controls had fewer syndromes and fewer surgeries and this linkage was less prominent.

CONCLUSION

Among IC/BPS cases, the number of NBSs was strongly correlated with the number of surgeries. Understanding temporal relationships will be necessary to explore causal linkages and may modify surgical practice.

[Fibromyalgia syndrome as a psychosomatic disorder - diagnosis and therapy according to current evidence-based guidelines]

OBJECTIVES

The classification and therapy of patients with chronic widespread pain without evidence of somatic factors as an explanation is currently a matter of debate. The diagnostic label "fibromyalgia syndrome"(FMS) has been rejected by some representatives of general and psychosomatic medicine.

METHODS

A summary is given of the main recommendations from current evidence-based guidelines on FMS and nonspecific/functional/somatoform bodily complaints.

RESULTS

The criteria of FMS and of persistent somatoform pain disorder or chronic pain disorder with somatic and psychological factors partly overlap. They include differential clinical characteristics of persons with chronic widespread pain but without sufficiently explaining somatic factors. Not all patients diagnosed with FMS meet the criteria of a persistent somatoform pain disorder. FMS is a functional disorder, in which in most patients psychosocial factors play an important role in both the etiology and course of illness. FMS can be diagnosed by looking at the history of a typical symptom cluster and excluding somatic differential diagnoses (without a tender point examination) using the modified 2010 diagnostic criteria of the American College of Rheumatology. Various levels of severity of FMS can be distinguished from a psychosomatic point of view, ranging from slight (single functional syndrome) to severe (meeting the criteria of multiple functional syndromes) forms of chronic pain disorder with somatic and psychological factors, of persistent somatoform pain disorder or of a somatization disorder. The diagnosis of FMS as a functional syndrome/stress-associated disorder should be explicitly communicated to the patient. A therapy within collaborative care adapted to the severity should be provided. For long-term management, nonpharmacological therapies such as aerobic exercise are recommended. In more severe cases, psychotherapy of comorbid mental disorders should be conducted.

CONCLUSIONS

The coordinated recommendations of both guidelines can synthesize general medical, somatic, and psychosocial perspectives, and can promote graduated care of patients diagnosed with FMS.

Affective spectrum disorders in an urban Swedish adult psychiatric unit: a descriptive study

Background. Several studies have found that patients with affective-/anxiety-/stress-related syndromes present overlapping features such as cooccurrence within families and individuals and response to the same type of pharmacological treatment, suggesting that these syndromes share pathogenetic mechanisms. The term affective spectrum disorder (AfSD) has been suggested, emphasizing these commonalities. The expectancy rate, sociodemographic characteristics, and global level of functioning in AfSD has hitherto not been studied neglected. Material and Method. Out of 180 consecutive patients 94 were included after clinical investigations and ICD-10 diagnostics. Further investigations included well-known self-evaluation instruments assessing psychiatric symptoms, personality disorders, psychosocial stress, adaptation, quality of life, and global level of functioning. A neuropsychological screening was also included. Results. The patients were young, had many young children, were well educated, and had about expected (normal distribution of) intelligence. Sixty-one percent were identified as belonging to the group of AfSD. Conclusion. The study identifies a large group of patients that presents much suffering and failure of functioning. This group is shared between the levels of medical care, between primary care and psychiatry. The term AfSD facilitates identification of patient groups that share common traits and identifies individuals clinically, besides the referred patients, in need of psychiatric interventions.

Diagnosis and differential diagnosis of fibromyalgia

Fibromyalgia is a chronic functional illness that presents with widespread musculoskeletal pain as well as a constellation of symptoms including fatigue, cognitive dysfunction, sleep difficulties, stiffness, anxiety, and depressed mood. The diagnosis of fibromyalgia, similar to other functional disorders, requires that organic diseases are not causing the symptoms. Systemic and rheumatic diseases can be ruled out by a patient history, physical examination, and laboratory investigations. Because there are no specific laboratory tests for fibromyalgia, the 1990 American College of Rheumatology (ACR) classification criteria have been used in clinical settings; however, they are not ideal for individual patient diagnosis. Clinicians should be aware of limitations inherent in using tender points in the diagnosis of fibromyalgia. The multiple symptoms of fibromyalgia often overlap with those of related disorders and may further complicate the diagnosis. One of the most challenging diagnostic dilemmas that clinicians face is distinguishing fibromyalgia from other central pain disorders (e.g., irritable bowel syndrome, chronic fatigue syndrome, migraine). Screening questions based on published criteria can be used as a first approach in diagnosing functional illnesses. Numerous studies report a higher prevalence of psychiatric disorders in patients with fibromyalgia. Therefore, a careful history and evaluation should be taken for the presence of primary mood disturbances. To date, there is no "gold standard" for diagnosing fibromyalgia. Until a better clinical case definition of fibromyalgia exists, all diagnostic criteria should be interpreted with caution, considered rudimentary, and subject to modification.

Duloxetine in the treatment of irritable bowel syndrome: an open-label pilot study

OBJECTIVE

To assess the efficacy of duloxetine for irritable bowel syndrome (IBS).

METHODS

We conducted an open-label 12-week trial of duloxetine 60 mg daily in 15 patients with IBS without concurrent major depressive disorder. The primary outcome measure was average abdominal pain. Secondary measures included IBS symptoms, Clinical Global Impression-Severity, Hamilton Anxiety Rating Scale, IBS Quality-of-Life Scale, and Sheehan Disability Scale. We analyzed changes using random regression and one-sample t-tests.

RESULTS

Fourteen patients completed at least one post-baseline evaluation; eight completed the study. Duloxetine was associated with significant improvement (p < 0.05) in pain, severity of illness, quality of life, loose stool, work and family disability, and anxiety. However, duloxetine did not improve hard stool. Although we found no evidence of serious duloxetine toxicity, seven participants withdrew over the course of the study because of adverse drug events.

CONCLUSIONS

In this small, open-label study, duloxetine appeared to be effective for many features of IBS, but its adverse effects, most notably constipation, limited its use. Since our study excluded individuals with concurrent major depression, it appears that duloxetine may benefit IBS independently of its antidepressant effects. These encouraging but preliminary open-label findings support further investigation of duloxetine treatment in placebo-controlled trials of IBS.

History of depressive and anxiety disorders and paroxetine response in patients with irritable bowel syndrome: post hoc analysis from a placebo-controlled study

OBJECTIVE

Although irritable bowel syndrome (IBS) is highly comorbid with depressive and anxiety disorders, information on the clinical implications of this comorbidity is limited. We investigated whether a history of depressive and/or anxiety disorders was associated with response to treatment in a double-blind, randomized, placebo-controlled trial of paroxetine controlled release (CR) in IBS.

METHOD

Seventy-two IBS subjects (diagnosed using Rome II criteria) were recruited from August 2003 to November 2005 and randomly assigned to receive flexibly dosed paroxetine CR (dose, 12.5-50 mg/day) or placebo for 12 weeks. The Mini-International Neuropsychiatric Interview (MINI-Plus version) was used to ascertain current (exclusionary) or past diagnoses of depressive and anxiety disorders. Subjective depression, anxiety, and stress were assessed at entry and throughout the trial using the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Perceived Stress Scale (PSS). Severity of IBS symptoms was determined by the Composite Pain Score (CPS), administered via Interactive Voice Response System, and the Clinical Global Impressions scale (CGI). The primary outcome was treatment response defined as ≥ 25% reduction in CPS from randomization to end of treatment. A post hoc analysis (multivariate logistic regression) was done to evaluate whether a history of depressive and/or anxiety disorder was associated with response to medication.

RESULTS

Baseline demographic and clinical characteristics (CPS, BDI, BAI, PSS, CGI scores) were similar between groups (history of depressive/anxiety disorder vs. no history). In multivariate logistic regression analysis, treatment response was not predicted by history of depressive and/or anxiety disorder (OR = 0.58, CI = 0.29 to 1.68, p = .32) or drug status (paroxetine CR vs. placebo) (OR = 1.26, CI = 0.68 to 3.21, p = .19). Drug status was significantly associated with the secondary outcome variable of treatment response as defined by a CGI improvement score of 1 to 2 (OR = 12.14, CI = 2.9 to 48.4, p < .001). Paroxetine CR was safe and well tolerated during the study.

CONCLUSIONS

History of depressive and/or anxiety disorder was not associated with response of IBS symptoms to paroxetine CR. Conclusions are limited due to insufficient statistical power. Further research is needed to clarify the role of selective serotonin reuptake inhibitors in the treatment of IBS and to elucidate the treatment ramifications of comorbid psychiatric disorders.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00610909.

Is there a predisposition for the development of autoimmune diseases in patients with fibromyalgia? Retrospective analysis with long term follow-up

The objectives of the study were to evaluate the prevalence of antinuclear antibodies (ANA) in patients with fibromyalgia (FM) and the probability of the development of clinically overt connective tissue diseases. Four hundred and fifty FM patients were compared to 129 healthy matched blood donors. ANA testing was performed by immunofluorescence on rat tissue sections; in case of highly positive results, ANA were specified further by ELISA and immunodiffusion. All ANA positive FM patients were invited for a control examination. The ANA negative patients received a questionnaire, which was designed to identify those patients with possible connective tissue diseases (CTD). There was no significant difference in the frequency of ANA or thyroid antibodies between patients and controls (11.6% vs. 7%). Two patients had developed SLE: one was already ANA/anti-dsDNA positive at time of first diagnosis of FM; in the other, specific antibodies and SLE-related symptoms developed after 4.5 years. The probability for FM patients to develop CTD (SLE) within one year is 0.0027%, which is comparable to the incidence of SLE in the general population (0.005%). The risk of CTD is not increased in FM. The detection of ANA does not predict the development of CTD. However, in individual cases, FM may be an early sign of an autoimmune disease.

Family study of fibromyalgia and affective spectrum disorder

BACKGROUND

Fibromyalgia is one member of a proposed group of psychiatric and medical disorders, collectively termed affective spectrum disorder (ASD), hypothesized to share possibly heritable pathophysiologic features. Two predictions of the ASD hypothesis were tested: ASD, taken as a single entity, aggregates in families; and fibromyalgia coaggregates with other forms of ASD in families.

METHODS

Probands with and without fibromyalgia, together with their first-degree relatives, were administered structured diagnostic interviews. Noninterviewed relatives were diagnosed according to information provided by interviewed relatives. Aggregation and coaggregation of disorders were analyzed with proband predictive logistic and linear regression models.

RESULTS

In 533 relatives of 78 probands with fibromyalgia and 272 relatives of 40 probands without fibromyalgia, the estimated odds ratio (OR) (95% confidence interval) for the familial aggregation of ASD was 1.8 (.97, 3.2), p = .065, and the increase in number of forms of ASD in a relative for each additional form of ASD in a proband was .076 (.027, .1240), p = .002. The OR for the coaggregation of fibromyalgia with other forms of ASD was 2.0 (1.2, 3.2), p = .004; this remained significant even after excluding all mood-disorder diagnoses: 1.8 (1.1, 3.0), p = .012.

CONCLUSIONS

These findings support familial aggregation of ASD collectively and familial coaggregation of fibromyalgia with other forms of ASD.

The overtraining syndrome in athletes: a stress-related disorder

Physical exercise is a type of allostatic load for several endocrine systems, notably the hypothalamic-pituitary-adrenal (HPA) axis. Athletes undergoing a strenuous training schedule can develop a significant decrease in performance associated with systemic symptoms or signs: the overtraining syndrome (OTS). This is a stress-related condition that consists of alteration of physiological functions and adaptation to performance, impairment of psychological processing, immunological dysfunction and biochemical abnormalities. Universally agreed diagnostic criteria for OTS are lacking. The pituitary-adrenal response to a standardized exercise test is usually reduced in overtrained athletes. This HPA dysfunction could reflect the exhaustion stage of Selye's general adaptation syndrome. The most attractive hypothesis that accounts for the observed neuro-endocrine-immune dysregulation is the Smith's cytokine hypothesis of OTS. It assumes that physical training can produce muscle and skeletal trauma, thus generating a local inflammatory reaction. With the excessive repetition of the training stimulus the local inflammation can generate a systemic inflammatory response. The main actors of these processes are the cytokines, polypeptides that modulate HPA function in and outside the brain at nearly every level of activity. It is hoped that future research will focus on endogenous risk factors for morbidities related to the neuro-endocrine-immune adaptation to exercise.

Comorbidity of Fibromyalgia and Posttraumatic Stress Disorder Symptoms in a Community Sample of Women

OBJECTIVE

To test alternative explanations for the comorbidity between fibromyalgia (FM), a medically unexplained syndrome involving widespread pain, and posttraumatic stress disorder (PTSD). In contrast to a default "risk factor" hypothesis, tested hypotheses were that: A) The association is due to a sampling bias introduced by the study of care-seeking individuals; B) FM is an additive burden that strains coping resources when confronting life stress; and C) Arousal symptoms of PTSD and FM are confounded.

DESIGN

Community-dwelling women in the New York/New Jersey metropolitan area (N=1,312) completed a telephone survey regarding FM-like symptoms prior to September 11, 2001. Approximately 6 months after the World Trade Center terrorist attacks, they again completed the survey, to which questions regarding PTSD symptoms were added.

RESULTS

The odds of probable PTSD were more than three times greater in women with FM-like symptoms, both assessed after 9/11. The odds ratio was not reduced by controlling for FM-like symptoms before 9/11 or for the potentially confounded symptoms of PTSD specifically related to arousal.

CONCLUSIONS

These findings lead us to reject alternate explanations for the comorbidity between FM and PTSD. Speculations that FM and PTSD share psychobiological risk factors remain plausible.

Common genetic risk factors for psychiatric and simatic disorders

There is increasing knowledge about considerable comorbidity between psychiatric and somatic diseases, questioning whether variations in genes could be predisposing factors for both conditions. With respect to the multiple interactions between brain and body investigations have centered on variants in several candidate genes for proteins that mediate these interactions and therefore also have implications in psychiatric disorders. The available data, although still preliminary and rare, indicate the importance of polymorphic variants in genes coding for the serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT), the 5-HT_2A receptor, proinflammatory cytokines, and the angiotensin-converting enzyme (ACE) in migraine, fibromyalgia, cardiovascular disorders, and psychiatric conditions. The role played by these various polymorphisms remains to be determined, as does whether they are indicative of common pathophysiological mechanisms or identify a subgroup of patients with somatic disorders that are more closely related to psychiatric symptoms. Nevertheless, they do at least illustrate the potential influence of genetic differences on illness course and treatment outcome, and might be a rational approach to drug development and treatment paradigms.

Altered dopamine D2 receptor function in fibromyalgia patients: a neuroendocrine study with buspirone in women with fibromyalgia compared to female population based controls

BACKGROUND

To what extent fibromyalgia belongs to affective spectrum disorders or anxiety spectrum disorders remains disputed. Buspirone induces a hypothermic response, which most likely is due to 5-HT(1A) autoreceptor stimulation, and growth hormone (GH) release, which probably is related to postsynaptic 5-HT(1A) receptor stimulation. The prolactin response to buspirone has been suggested to be mediated through dopamine (DA) antagonistic effects.

OBJECTIVES

Based on the assumption that fibromyalgia is more strongly related to stress and anxiety than affective spectrum disorders, we hypothesized that compared to population controls, fibromyalgia patients should demonstrate an increased prolactin response (DA sensitivity) to buspirone challenge test, but no difference in hypothermic response or GH release (5HT sensitivity).

METHOD

A 60-mg dose of buspirone was given orally to 22 premenopausal women with fibromyalgia and 14 age and sex matched healthy control subjects. Core body temperature, growth hormone and prolactin levels were analyzed at baseline and after 60, 90, and 150 min.

RESULTS

Fibromyalgia patients showed an augmented prolactin response to buspirone compared to controls. Temperature and growth hormone responses did not differ from controls.

CONCLUSIONS

Dopaminergic rather than serotonergic neurotransmission is altered in fibromyalgia, suggesting increased sensitivity or density of dopamine D(2) receptors in fibromyalgia patients. Stress and anxiety is an important modulator of dopaminergic neurotransmission. Our results suggest that fibromyalgia is related to anxiety and associated with disturbance in the stress response systems.

Person-centered approach to care, teaching, and research in fibromyalgia syndrome: justification from biopsychosocial perspectives in populations

OBJECTIVES

To describe complex interactions of multiple factors believed to contribute to fibromyalgia syndrome (FMS) at a person-centered level to enhance approaches to care, teaching, and research. The main factors addressed were central nervous system sensory sensitization, autonomic nervous system (ANS) activation, neurohumoral perturbations, and psychosocial and environmental stressors. A person-centered approach is defined as attention to major biopsychosocial issues of affected individuals.

METHODS

Literature on classification, mechanistic pathways, course and outcomes, and management of FMS was reviewed to assess applications of person-centered approaches to care, teaching, and research. Various biopsychosocial influences were considered in relation to the heterogeneous subjective manifestations of this illness, including central hyperalgesia, ANS and other neurohumoral perturbations, functional hyperexcitability, nonrestorative sleep, and psychologic distress.

RESULTS

A person-centered approach to FMS can expand on and strengthen traditional biomedical concepts. Adding such a focus can help to untangle current controversies in the course, outcomes, and treatment of FMS. A person-centered approach can also help in the subgrouping of affected patients for greater specificity in care programs and in improved clinical investigations. In the biomedical model, diverse symptoms of FMS are often addressed separately and apart from their interconnectedness and linkages to the patient's individualized biopsychosocial factors. However, the causes of FMS symptomatology are not likely to be caused by uniform biologic abnormalities across populations. Rather, the syndrome likely results from personal reactivities to varied multifactorial biopsychosocial influences. Common denominators among individuals may include varying degrees of ANS activation (or personal susceptibility to ANS activation), nonrestorative sleep, negative affectivity, and other central pain sensitization mechanisms, among the pathways reviewed.

CONCLUSIONS

Innovative analytical methodologies will need to be developed to more effectively investigate complex interacting biopsychosocial dynamics at a person-centered level, including qualitative research, and multifactorial and multilevel techniques. Adding person-centered approaches to biopsychosocial concepts of FMS promises to show new physiopathogenetic insights and more effective treatment than current biomedical models alone. Person-centered approaches enhance patient-physician relationships and help prioritize patients' goals in mutually derived treatment plans.

Panic disorder, somatization, and the new cross-cultural psychiatry: the seven bodies of a medical anthropology of panic

This article aims to adduce a framework that will allow for the cross-cultural study of panic disorder. The authors take sensation as the key unit of analysis, aiming to contribute to a medical anthropology of sensation. The seven analytic perspectives that are suggested in the article are the following: the full spectrum of panic attack sensations (the sensation body), the biological generation of panic sensations (the biological body), sensation as invoking an ethnophysiology (the ethnophysiological body), sensation as metaphor (the metaphoric body), sensation as invoking the landscape (the landscape body), sensation as invoking catastrophic cognitions (the catastrophic cognitions body), and sensation as invoking memory (the memory-associational body).

Treatment of fatigue in fibromyalgia

Clearly, fatigue is a large and challenging problem for those suffering from fibromyalgia. It adds greatly to the morbidity and disability associated with the disease. In the management of this specific symptom in fibromyalgia, attention should first be focused on identifying comorbidities that may be present and contribute to fatigue. As with other symptoms of fibromyalgia, education is a critical component of management. This can be done by the practitioner, with available free resources, or with specialized cognitive behavioral programs. This education process can be augmented with a variety of other nonpharmacologic therapies, especially very gradually increasing, low-impact, aerobic exercise programs. Numerous pharmacologic therapies may also be helpful as an adjunct to treatment. Classes of compounds that raise central levels of norepinephrine or dopamine appear to be the most specific for management of fatigue. There are also many medications used to combat fatigue in other disorders that have not yet been adequately explored as to the possible benefits in alleviating the fatigue of fibromyalgia. Advances in the management of fatigue in fibromyalgia are likely to come from a variety of directions. Easier access to well designed nonpharmacologic therapies is essential, because these treatments are underutilized in clinical practice at present. Improvements in pharmacologic therapies will come from new insights into mechanisms, especially those that might only be present in subsets of patients and would respond to more targeted therapies.

Childhood victimization and pain in adulthood: a prospective investigation

Evidence of the relationship between childhood abuse and pain problems in adulthood has been based on cross-sectional studies using retrospective self-reports of childhood victimization. The objective of the current study was to determine whether childhood victimization increases risk for adult pain complaints, using prospective information from documented cases of child abuse and neglect. Using a prospective cohort design, cases of early childhood abuse or neglect documented between 1967 and 1971 (n = 676) and demographically matched controls (n = 520) were followed into young adulthood. The number of medically explained and unexplained pain complaints reported at follow-up (1989-1995) was examined. Assessed prospectively, physically and sexually abused and neglected individuals were not at risk for increased pain symptoms. The odds of reporting one or more unexplained pain symptoms was not associated with any childhood victimization or specific types (i.e. sexual abuse, physical abuse, or neglect). In contrast, the odds of one or more unexplained pain symptoms was significantly associated with retrospective self-reports of all specific types of childhood victimization. These findings indicate that the relationship between childhood victimization and pain symptoms in adulthood is more complex than previously thought. The common assumption that medically unexplained pain is of psychological origin should be questioned. Additional research conducting comprehensive physical examinations with victims of childhood abuse and neglect is recommended.

The potential role of hypocortisolism in the pathophysiology of stress-related bodily disorders

Representing a challenge for current concepts of stress research, a number of studies have now provided convincing evidence that the adrenal gland is hypoactive in some stress-related states. The phenomenon of hypocortisolism has mainly been described for patients, who experienced a traumatic event and subsequently developed post-traumatic stress disorder (PTSD). However, as presented in this review, hypocortisolism does not merely represent a specific correlate of PTSD, since similar findings have been reported for healthy individuals living under conditions of chronic stress as well as for patients with several bodily disorders. These include chronic fatigue syndrome, fibromyalgia, other somatoform disorders, rheumatoid arthritis, and asthma, and many of these disorders have been related to stress. Although hypocortisolism appears to be a frequent and widespread phenomenon, the nature of the underlying mechanisms and the homology of these mechanisms within and across clinical groups remain speculative. Potential mechanisms include dysregulations on several levels of the hypothalamic-pituitary adrenal axis. In addition, factors such as genetic vulnerability, previous stress experience, coping and personality styles may determine the manifestation of this neuroendocrine abnormality. Several authors proposed theoretical concepts on the development or physiological meaning of hypocortisolism. Based on the reviewed findings, we propose that a persistent lack of cortisol availability in traumatized or chronically stressed individuals may promote an increased vulnerability for the development of stress-related bodily disorders. This pathophysiological model may have important implications for the prevention, diagnosis and treatment of the classical psychosomatic disorders.

The T102C polymorphism of the 5-HT2A-receptor gene in fibromyalgia

Based on a possible involvement of serotonergic dysfunction in the pathophysiology of fibromyalgia (FM) and on preliminary reports of a possible genetically driven vulnerability for this disorder we investigated the silent T102C polymorphism of the 5-HT2A-receptor gene in 168 FM patients and 115 healthy controls. Our results showed a significantly different genotype distribution in FM patients with a decrease in T/T and an increase in both T/C and C/C genotypes as compared to the control population (Fisher's Exact test, two-sided, P = 0.008). However, the increase in allele-C102 frequency felt short of significance (P = 0.07). Correlation of genotypes to clinical parameters revealed no influences on age of onset, duration of disease or psychopathological symptoms, measured with the Beck Depression Inventory and the symptom checklist SCL-90-R. In contrast to that the pain score, being a self reported information on pain severity, was significantly higher in patients of the T/T genotype (Mann-Whitney U test, P = 0.028). This suggests that the T102-allele might be involved in the complex circuits of nociception. However, the T102C polymorphism is not directly involved in the aetiology of FM but might be in linkage dysequilibrium with the true functional variant, which has to be unravelled.

Hormonal pertubations in fibromyalgia syndrome

The symptomatology characterizing fibromyalgia (FM) comprises three systems: the musculoskeletal system with widespread muscular pain, neuroendocrine disorders, and psychological distress including depression. Though the most prominent symptom of FM is pain in defined points of the musculoskeletal system, the numerous other somatoform and psychological disorders suppose a common primary disturbance which we consider to originate within higher levels of the central nervous system. Recent studies of the entire endocrine profile of FM patients following a simultaneous challenge of the hypophysis with corticotropin-releasing hormone (CRH), thyrotropin-releasing hormone, growth hormone-releasing hormone, and luteinizing hormone-releasing hormone support the hypothesis that an elevated activity of CRH neurons determines not only many symptoms of FM but may also cause the deviations observed in the other hormonal axes. Hypothalamic CRH neurons thus may play a key role not only in "resetting" the various endocrine loops but possibly also nociceptive and psychological mechanisms as well.