Depression and medication-adherence in patients with hypertension attending a tertiary health facility in South-West Nigeria

INTRODUCTION: In Nigeria, approximately 4.33 million adults suffer from hypertension and about a third of them do not adhere to prescribed medications. Depression has been reported to significantly predict poor medication adherence. The relationship between medication non-adherence and co-morbid depressive disorder in patients with hypertension has not been adequately explored in this environment. The study aimed to determine the prevalence of depression in patients with hypertension. The association between socio-demographic characteristics and presence of co-morbidity on medication adherence was also determined. METHODS: A cross-sectional descriptive research design was adopted for the study. A socio-demographic questionnaire, the modified Morisky Medication Adherence Scale (MMAS), the Hamilton Rating Scale for Depression (HAM-D) and the Mini International Neuropsychiatric Interview (MINI), were administered to four hundred patients with hypertension attending medical out-patient clinic between August and September 2012. RESULTS: About 43% (168) were aged 61 to 64 years the majority being females, with a female to male ratio of 1.63:1. The prevalence of comorbid depression was 22.8%, made up of mild (21.8%) and moderate (1.0%) depressive episodes only. Depression was commoner among females than males in a ratio of 3:1. A majority of the participants (96.8%) had high medication adherence; 2.8% and 0.4% had moderate and low adherence respectively. Depression was more among patients with good medication adherence. CONCLUSION: The occurrence of mild depressive disorder among hypertensives did not affect the level of medication adherence. Review of Antihypertensive drugs should also be done often to ensure patients are not likely to have depressive illness as a side effect of drugs used.