To study the prevalence and clinical characteristics of Somatic Symptom Disorder (SSD), Bodily Distress Syndrome (BDS) and fibromyalgia syndrome (FMS) and their overlap in the general German population.
A cross-sectional nationally representative population survey was performed. 2531 participants (mean age 48.8 ± 17.85 years, 53.3% women) completed the Somatic Symptom Scale SSS-8, the Bodily Distress Syndrome (BDS) 25 checklist, the Whiteley Index 7 (WI-7), the self-administered comorbidity questionnaire and the Michigan Body Map. Case definitions of SSD, BDS and FMS were assigned using established criteria.
4.5% of participants met the criteria of SSD (SSS - 8 at least one item "bothered very much" and WI- 7 total score ≥ 1). 9.6% met the criteria of single-organ BDS and 1.3% of multi-organ BDS. Prevalence of FMS according to 2016 criteria was 3.4%. 82.3% of FMS cases met any BDS criteria.28.1% of FMS cases satisfied SSD criteria. 28.8% of any BDS cases met the criteria of SSD. 75.1% of SSD cases met the criteria of any BDS. FMS cases reported the highest amount of somatic and psychological symptom burden and health anxieties. There were no differences in age and gender between any BDS and SSD cases. SSD cases reported worse general health and more fibromyalgia-related variables than any BDS cases.
In the general population, there is a substantial overlap between FMS and BDS, but not of FMS and SSD, and not of SSD and any BDS. Case definitions of the three disorders partially captured different groups in the general population.