Severe mental illness in the MENAT region: systematic review and meta-analysis of prevalence and comorbidities

Abstract

Severe mental illnesses (SMIs), including schizophrenia spectrum disorders, bipolar disorders, and severe major depressive disorder (MDD), contribute substantially to disability and premature mortality worldwide. Evidence from the Middle East, North Africa, and Türkiye (MENAT) region remains fragmented, with considerable variability in diagnostic approaches, study settings, and population characteristics. This systematic review and meta-analysis aimed to synthesise available evidence on the prevalence and comorbidity patterns of SMIs across MENAT countries while accounting for methodological heterogeneity. We conducted a systematic review and meta-analysis following PRISMA 2020 guidelines. Six databases and one trial registry were searched from January 2010 to September 2025. Random-effects meta-analysis using restricted maximum likelihood estimation was performed to estimate the pooled prevalence of SMIs and associated comorbidities. Stratified analyses were conducted by population type, diagnostic approach, and study characteristics. Publication bias and sensitivity analyses were performed, and methodological quality was assessed using the Joanna Briggs Institute tool. The study protocol was prospectively registered in PROSPERO (CRD420251152277). Out of 2775 initial hits, a total of 106 studies were included. Prevalence estimates varied substantially across study settings, diagnostic approaches, and populations, with substantial to extreme between-study heterogeneity (I 2 ranging from 96.1% to over 99%). In general-population samples, the pooled prevalence of SMI was 7.3% (95% CI: 5.0–9.5), whereas it was 31.1% (95% CI: 23.9–38.2) in clinical and high-risk samples. Across studies reporting comorbidities of SMIs, the pooled prevalence of comorbidities was 32.0% (95% CI: 25.5–38.6), with physical comorbidities being more common than psychiatric ones. Extreme heterogeneity and small-study effects limit the pooled estimates to broad summaries rather than precise regional prevalence estimates. The available evidence demonstrates that SMIs represent a substantial public health burden across the MENAT region, particularly in clinical and high-risk populations, and is accompanied by a high burden of physical comorbidity. However, substantial clinical and methodological heterogeneity limits the interpretation of pooled estimates as precise regional prevalence figures. Future epidemiological studies using standardised diagnostic approaches are needed to provide more precise estimates of disease burden in the region. Not applicable.