The German fibromyalgia consumer reports – a cross-sectional survey

Background Consumer surveys provide information on effectiveness and side effects of medical interventions in routine clinical care. A report of fibromyalgia syndrome (FMS) consumers has not been carried out in Europe. Methods The study was carried out from November 2010 to April 2011. Participants diagnosed with FMS rated the effectiveness and side effects of pharmacological and non-pharmacological FMS interventions on a 0 to 10 scale, with 10 being most efficacious (harmful). The questionnaire was distributed by the German League for people with Arthritis and Rheumatism and the German Fibromyalgia Association to their members and to all consecutive FMS patients of nine clinical centers of different levels of care. Results 1661 questionnaires (95% women, mean age 54 years, mean duration since FMS diagnosis 6.8 years) were analysed. The most frequently used therapies were self-management strategies, prescription pain medication and aerobic exercise. The highest average effectiveness was attributed to whole body and local warmth therapies, thermal bathes, FMS education and resting. The highest average side effects were attributed to strong opioids, local cold therapy, gamma-amino-butyric acid analogues (pregabalin and gabapentin), tramadol and opioid transdermal systems. Conclusion The German fibromyalgia consumer reports highlight the importance of non-pharmcological therapies in the long-term management of FMS, and challenges the strong recommendations for drug therapies given by FMS-guidelines.


Background
The key symptoms of fibromyalgia syndrome (FMS) are chronic widespread pain, unrefreshed sleep, cognitive dysfunction and fatigue [1,2]. Patients often report high disability levels and poor quality of life along with extensive use of medical care [3,4]. The prevalence of FMS was 2.9-3.8% in the general population of five European countries [5,6]. FMS can be diagnosed in clinical care by the American College of Rheumatology 2010 preliminary diagnostic criteria [1] and in surveys by the fibromyalgia survey diagnostic criteria [7].
The definitive etiology and pathophysiology of FMS are unknown [8]. A great variety of pharmacological and non-pharmacological therapies are offered to and used by patients to relieve symptoms [9]. Evidence-based guidelines aim to guide patients and health care providers in the choice of treatment options [10][11][12]. These guidelines rely on randomised controlled trials of pharmacological and non-pharmacological therapies. However, the external validity of RCTs in FMS is limited: Most studies excluded patients with inflammatory rheumatic diseases and severe mental disorders and were conducted in research and university centers [13]. Consumer reports, in which patients assess the effectiveness and side effects of interventions, can supplement the results of RCTs, because participants are not excluded because of comorbidities [13]. The US National Fibromyalgia Association (NFA) conducted an internet survey in which 2596 participants responded about the effectiveness of FMS-treatments in 2005. Side effects were not assessed [14].
Given the limited external validity of RCTs in FMS, we conducted the first European FMS consumer reports on the effectiveness and side effects of FMS-therapies in routine clinical care.

Recruitment
Participants of the study were recruited by the two largest German FMS-self help organisations and nine clinical institutions. The specialties of the clinical institutions were pain medicine and psychotherapy (N = 3), rheumatology (N = 2), complementary and alternative medicine (N = 2), physical therapy (N = 1) and pain therapy (N = 1). The settings were outpatient (N = 6), inpatient (N = 2) and day clinic (N = 1). The levels of care were secondary (N = 6) and tertiary care (N = 2) and rehabilitation (N = 1).

Inclusion-and exclusion criteria
Members of the self-help organisations had to report that the diagnosis of FMS had been established by a physician. Because there is no gold standard for the clinical diagnosis of FMS [15], the physicians of the participating study centers were free in their choice of FMS-diagnostic criteria. Patients who were not able to read German and patients with a FMS-diagnosis of <1 month's duration were excluded. There were no other exclusion criteria.

Clinical institutions
From November 1, 2010 to April 30, 2011 all consecutive patients with an established diagnosis of FMS at the participating study centres were asked by the physicians of these centres to take part in the study. The questionnaires were handed out by the physicians of the centres with a standardized letter explaining the focus of the study. The questionnaires were returned by the patients in a closed and anonymous envelope and kept away from the charts. At the end of the study the questionnaires were sent to the coordinating study centre.

Self-help organisations
The package of questionnaires was sent by the central office of the German League for people with Arthritis and Rheumatism to their regional offices with the request that the leaders of the local self-help groups distribute the questionnaires to their members during group meetings. The German Fibromyalgia Association included the package in the 4/2010 issue of its member journal "Optimist,"which was sent out by post to all members. Patients returned the questionnaires by post at their own cost to the central office. In addition, the questionnaires were available on the homepages of both self-help organisations. After downloading and completing the completed questionnaires, they were sent by mail, fax or email to the central offices. Employees of both central offices removed personal identifying information and sent the questionnaires to the coordinating study centre.
The participants (investigators and patients) of the study did not receive any reimbursement or compensation for participation.

Survey questionnaires
Demographic data and medical data were assessed by a questionnaire used in a previous multicenter German FMS-study [16].
The questionnaire "Benefits and harms of FMStherapies" was delevoped by the heads of the clinical centers taking part in the study and by the directors of the two FMS self-help organisations. Similar to the NFAquestionnaire [14], survey participants were asked to "indicate whether you currently use any of the following interventions for FMS and if so, whether each helps to relieve your FMS symptoms". Moreover, the patients were asked if they had used these interventions in the past. Respondents rated the effectiveness (relief of symptoms) and harms (side effects) of each intervention used in the present or past on a 0 to 10 scale, with 10 being most effective (harmful). The interventions were listed in different sections: Self-management strategies (exercise, resting, physical modalities), psychological therapies, drugs and complementary/alternative medicine (CAM) (a copy of the questionaire is available on request). Face validity and understandability of the questionnaire were qualitatively validated by four clinicians (rheumatology, pain medicine, psychosomatic medicine) and 10 patients (integrative medicine, pain medicine) not involved in the study. Eight questioniare items were modified according to the validation reports.
The 4-item Patient Health Questionnaire-4 (PHQ-4) is an ultra-brief self-report questionnaire that consists of a 2-item depression scale (PHQ-2) and a 2-item anxiety scale (GAD-2). A score of ≥ 3 on the depression subscale represents a reasonable cut-point for identifying potential cases of major depression or other depressive disorders; a score of ≥3 on the anxiety subscale represents a reasonable cut-point for generalized anxiety, panic, social anxiety, and posttraumatic stress disorders [17]. We used the validated German version of the PHQ 4 [18].

Statistical analysis
The data were entered by four pairs of study assistants into a preconstructed data sheet. The entering of data was randomly checked by two authors, and further checked for plausibility during descriptive data analysis. Missing values were not replaced. Descriptive statistics were performed by Winstat for Excel (R. Fitch Software, Bad Krozingen, Germany, 2010).

Ethics
Study investigators respected the requirements of data protection and medical professional secrecy. The study was approved by the ethical committee of the Ludwig Maximilian Universität München.

Study participants
There were no data available about how many patients contacted by the self-help organisation declined to participate in the study. The German League for people with Arthritis and Rheumatism estimated that 10,000 of their members were FMS patients. The German Fibromyalgia Association indicated that 4,000 members have FMS.
123 patients of the clinical samples did not meet the primary inclusion criteria and 40 of the contacted patients refused to take part in the study. 1,661 questionnaires were analysed. The total study sample was composed mainly of middle-aged women with long durations of CWP and time from FMS diagnosis (see Table 1). 1411 (85.5%) participants met the fibromyalgia survey diagnostic criteria [7]. 276/1351 (20.4%) participants reported a diagnosis of an inflammatory rheumatic

Most frequently used interventions
The most frequently used types of current interventions were self-management strategies, prescription pain medication and aerobic exercise (see Table 2).

Effectiveness and side effects
The highest average effectiveness was attributed to whole body warmth therapies (biosauna, infrared cabin, warmth bathes), thermal bathes, FMS education and resting and local warmth therapy (see Table 3). The highest average side effects were attributed to strong opioids, local cold therapy, gamma-amino-butyric acid analogues (GABA) (pregabalin, gabapentin), tramadol and opioid transdermal opioid systems (see Table 4). The frequency of use and the perceived benefits and harms of some therapies depended on some demographic (e.g. member of self-help group) and some clinical characteristics (e.g. comorbid inflammatory rheumatic disease and probable depressive disorder) (Jung et al., submitted).

Summary of main results
We conducted the first European FMS consumer reports. 1661 FMS patients participated. In contrast to randomised controlled trials, patients with comorbid inflammatory rheumatic diseases and mental disorders were included. Self-management strategies were the most frequently types of interventions currently used by the participants. Participants attributed the highest effectiveness to the relief of FMS-symptoms by nonpharmacological treatments (warmth therapy, balneotherapy, education). In contrast, strong opioids and GABA-analogues (pregabalin, gabapentin) were associated with the strongest side effects.

Comparison with other studies
The most frequently used therapies of the German and of the NFA-study [15] were resting and distraction. Aerobic exercise, prescribed analgesics and strength training were more frequently used by German compared to US survey participants. Antidepressants, prescribed sleep medication, nutritional supplements, massage and cold therapy were more frequently used by US than by German consumers. Both US and German survey participants indicated that resting, heat modalities and massage were the most effective therapies. German FMS-consumers reported less benefits from drug therapies than US American FMS-consumers (see Table 5).
Internet-based consumer reports can provide additional information on the effectiveness and side effects of therapies. "PatientsLikeme" is a social networking health internet webpage that enables its members to share conditions, treatment, and symptom information in order to monitor their health over time and learn from real-world outcomes. Patients can evaluate the effectiveness and type of side effects of drug therapies. 2084 (12%) of the FMS-patients registered in PatientsLikeme  were currently on treatment with duloxetine and 1899 (11%) with pregabalin. The majority of the patients attributed a moderate efficacy to all of these drugs. 542 FMSpatients reported discontinuation of duloxetine and 687 to stopped pregabalin because of adverse effects [19].

Limitations
Methodological problems such as retrospective design, lack of a control group, unspecified time frame, global assessment of effectiveness and side effects and lack of other assessment instruments than self-reports are inherent in effectiveness studies in a natural design such as used in the consumer reports [20]. Additional major methodology limitations of the design of this study were as follows: the different modalities of the distribution and recollection of the questionnaires led to a relevant number of missing data; the unknown response rate of the participants recruited by self-help organisations limited the generalizability of the results; and selection bias with respect to patients and study investigators preferring non-pharmacological and complementary therapies could not be excluded. While this study is the largest European consumer review to-date, the results still represent a relatively small sample of the overall available population.

Conclusions
Consumer reports represent a complementary source of information on therapeutic effectiveness and side effects, and may support treatment decisions of patients and physicians.
The German FMS consumer reports highlight the importance of self-management strategies and nonpharmacological treatment options in the long-term management of FMS, and challenge the strong recommendations for drug therapy of FMS given by FMS-guidelines [11][12][13].
Health webpages should allow the evaluation of nonpharmacological therapies, and future FMS-consumer reports should include measures of function to provide a broader context for study findings.