Chronic Conditions, New Onset, and Persistent Disability in the Ibadan Study of Aging

Information about the contribution of chronic conditions to disability in the sub-Saharan African older persons is derived from implicit data. We investigated the association of chronic conditions with incident and persistent disability among community-dwelling elderly Nigerians.

We followed disability-free participants in a household cluster randomized sample of 2,149 Nigerians, aged 65 years or older, in three waves over 5 years (2003-2009). Disability was measured using culturally adapted tools. Dementia and depression were ascertained using validated interviewer-administered measures. The presence of pain in six sites, angina, systemic hypertension, diabetes, heart and respiratory disease, and vision and hearing impairment were assessed using standardized self-report of clinician diagnoses. Independent predictors of disability were investigated using separate multivariate binomial and multinomial regression models with Bonferroni corrections.

Among 1,887 disability-free participants, 457 (24.2%) had incident disability over 5 years; there were 234 (12.4%), 177 (9.4%), and 106 (5.6%) new cases in each of the waves. A total of 181 (10.0%) persons had disability persistently. Having a pain condition (relative risk ratio [RRR] = 4.7, 95% confidence interval [CI] = 2.0-11.0), especially when nonlocalizing (RRR = 1.5, 95% CI = 1.0-2.2), was the main predictor of incident disability in the study. Dementia was associated with cumulative deaths over 5 years (RRR = 3.5, 95% CI = 2.3-5.3). There were no significant associations between having a chronic condition and persistent disability following correction for false discovery rates.

Using direct measurements, musculoskeletal pain appears to be the most disabling condition in this sub-Saharan African elderly cohort surviving for up to 5 years with chronic conditions. Dementia may be associated with early death.