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.