Prevalence of mental disorders among people with neurologic conditions in Nigeria: A systematic review

Background Mental disorders frequently coexist with neurological conditions, impacting the overall health, quality of life, and outcome of affected individuals. In Nigeria, where both neurological disorders and mental health challenges are prevalent, understanding the intersection of these comorbidities is crucial for improving patient outcomes. Objective This study aims to assess the prevalence of psychiatric disorders among people with neurologic conditions in Nigeria and to identify factors that may influence the prevalence rates. Methods Medical literature databases (PUBMED, EMBASE and African Journals Online) were systematically searched to identify published papers on the prevalence of mental disorders among people with neurologic conditions from 2010 to date. Meta-analysis to estimate the pooled prevalences were based on random effects models and heterogeneity was assessed using metaregression and subgroup analyses. Risk of bias in individual studies was evaluated using the NIH Quality Assessment Tool and confidence in the pooled prevalence estimates was assessed using the GRADE approach. Results Eighteen studies among 4,457 individuals were included. Among people with neurologic conditions in Nigeria, the pooled prevalence was approximately 17.6% (95% CI: 10.5%, 28.0%; I ²  = 97%; 15 studies; 3,832 individuals; low certainty) for major depression and 6.4% (95% CI: 3.9, 10.2; I ²  = 23%; three studies; 381 individuals; moderate certainty) for generalized anxiety disorder (GAD). Meta-regression indicated that major depression was more common with advancing age ( p- heterogeneity = 0.010), among females than males ( p- heterogeneity = 0.013), and in the southern regions of the country ( p- heterogeneity = 0.049). The pooled prevalence of major depression was approximately 26.92% (95% CI: 16.44%, 40.82%; I ²  = 95%) among stroke survivors and 11.90% (95% CI: 6.2%, 21.6%; I ²  = 92%) among people with epilepsy. Conclusion Psychiatric morbidity is highly prevalent among people with neurologic conditions in Nigeria and approaches to address both neurological and mental health needs simultaneously may be necessary.