Prevalence and Patterns of Depressive Disorder Among Children and Adolescents with Intellectual Disability in Sokoto, Northwest Nigeria

Background Depression is a significant comorbidity in children and adolescents with intellectual disability (ID), adversely affecting their quality of life and functional outcomes. While data from high-income countries exist, there is a critical scarcity of epidemiological studies on this subject in Sub-Saharan Africa, including Nigeria. This study aimed to determine the prevalence and socio-demographic and clinical correlates of depressive disorder among children and adolescents with ID in Northwestern Nigeria. Methods A cross-sectional study was conducted among 87 students with ID aged 6–18 years at a residential special school in Sokoto, Nigeria. Intellectual functioning was assessed using Raven's Progressive Matrices. Depression was diagnosed using the Kiddie-SADS-PL, administered by trained clinicians with adaptations for participants with limited verbal abilities, following the Diagnostic Manual–Intellectual Disability (DM-ID) guidelines. Data on socio-demographic and clinical characteristics were collected via a structured questionnaire. Multivariate logistic regression was used to identify independent determinants of depression. Results The overall prevalence of depressive disorder was 19.5% (17/87). A significant gender disparity was observed, with females being disproportionately affected (34.5%, 10/29) compared to males (12.1%, 7/58) (χ²=6.178, p = 0.013). The prevalence varied across levels of intellectual disability: mild ID (20.0%, 1/5), moderate ID (28.6%, 12/42), severe ID (10.5%, 4/38), and profound ID (0.0%, 0/2); however, this association was not statistically significant (p = 0.215). Multivariate analysis identified female gender (OR = 15.43, 95% CI: 1.89–125.85, p = 0.011), having an unemployed father (OR = 21.64, 95% CI: 1.22–384.37, p = 0.036), and lower paternal education (primary/secondary vs. tertiary: OR = 0.045, 95% CI: 0.01–0.31, p = 0.002) as significant independent correlates of depressive disorder. Conclusions Depression is highly prevalent among children and adolescents with intellectual disability in Northwestern Nigeria, with nearly one in five affected. The findings reveal significant vulnerability associated with female gender and socioeconomic factors like paternal unemployment and education. These results underscore the urgent need for integrating routine mental health screening and targeted, gender-sensitive interventions into the standard care provided at special education institutions in Nigeria and similar resource-limited contexts.