PREDICTORS OF MAJOR DEPRESSIVE DISORDER AMONG AGEING NIGERIANS

Abstract

Depression in older people has been identified as a new public health problem in low and middle income countries. The liability of depression among the elderly is often worsened by environmental and physical factors as they increase with age. Hence, elderly people appear to suffer the effect of the disorder much more than people in other age groups. Most studies on major depressive disorder (MDD) among elderly Nigerians have used cross-sectional designs which are descriptive in nature and have not investigated the effects of individual and environmental factors predicting it among the elderly people, over time. Therefore, this study determined factors predicting MDD among ageing Nigerians. The study was a retrospective analysis of a four year data from the Ibadan Study of Ageing (ISA). A total of 2,149 Yoruba-speaking elderly Nigerians from the states of Lagos, Ogun, Osun, Oyo, Ondo, Ekiti, Kogi and Kwara participated in the study between 2003 and 2009. MDD was assessed using the Geriatric Depression Scale (GDS), and was classified as "yes" for scores in the range of 10 - 30 and "no" for scores in the range of 0-9. Multilevel binary logistic models were used to determine factors predicting MDD among elderly Nigerians. Adjusted odds ratios (OR), 95% confidence intervals (95% CI), as well as, Intra-class Correlation Coefficients (ICC) for each random effect was estimated. Of the 2,149 study participants, 1,157 (53.8%) were females, and 555 (25.8%) dwelled in urban areas. At baseline 712 (31.1%) were in the 65-69 years age group while 648 (30.2%) were at least 80 years old. The overall prevalence of MDD was 27.34%. The differences in the occurrence of MDD among the elderly were attributable to differences between enumeration areas (6%) and individuals (22%). The statistically significant predictors of MDD were not keeping regular contact with family members (OR=2.91 (1.26-6.70), not keeping regular contact with friends (OR= 1.32 (1.05-1.67), not participating in family activity (OR=2.07 (1.63-2.43), not participating in community activity (OR= 1.93 (1.54-2.43), and good quality of health status (OR=0.25 (0.15-0.27). The study revealed that regular family contact, regular friend contact, family activity, community activity, and self reported quality of health were significantly associated with MDD among elderly Nigerians, over time. Elderly people living with depression are therefore advised to engage themselves more in social activities so as to reduce new onset of depression.