Prevalence and predictors of sub-optimal medication adherence among patients with severe mental illnesses in a tertiary psychiatric facility in Maiduguri, North-eastern Nigeria

INTRODUCTION: Sub-optimal adherence constitutes a significant impediment to the management of severe mental illnesses (SMIs) as it negatively impacts on the course of the illness and the treatment outcome. In this study, the levels of adherence, prevalence and the predictors of sub-optimal adherence were assessed in a sub-Saharan African setting. METHODS: Three hundred and seventy (370) respondents with diagnoses of schizophrenia, bipolar disorder or severe depression were randomly enrolled and interviewed at the out-patient department of the Federal Neuropsychiatric Hospital, Maiduguri in northeastern Nigeria. An anonymous sociodemographic questionnaire and a clinical proforma designed by the authors, Oslo social support scale and the 8-item Morisky Medication Adherence Scale (MMAS-8) were used for data collection. RESULTS: The prevalence of sub-optimal adherence was 55.7%. The independent predictors of sub-optimal adherence were; seeking for traditional/ spiritual treatment (Odds Ratio (O.R.) = 6.523, 95% C.I. = 3.773 - 11.279, P = < 0.001), male gender (O.R. = 3.307, 95% C.I. = 1.907 - 5.737, P = < 0.001), low levels of insight (O.R. = 1.753, 95 C.I. = 1.220 - 2.519, P = 0.002), and low social support levels (O.R. = 1.528, 95% C.I. = 1.097 - 2.129, P = 0.012). CONCLUSION: Based on the outcome of the study, we recommend the development of psycho-educational programmes on adherence and the active involvement of the relations and significant others in the management of patients with SMIs in sub-Saharan Africa.