Cognitive reserve and other determinants of cognitive function in older adults: Insights from a community-based cross-sectional study

BACKGROUND: India will be the home of 323 million elderly persons by 2050. This means a surge in the dependent population primarily due to age-related cognitive decline. Evidence suggests that life course factors may have a modulatory role on cognitive function. The present study explores such potential influence by investigating the effect of cognitive reserve (a latent construct using education and occupation) and physical, psychological, and social determinants on cognitive function in community dwelling elderly. METHODS: A community-based cross-sectional study was conducted in urban areas of West Bengal (India) among elderly aged ≥60 years. Data was collected by personal interviews for socio-demographic and medical profile. Cognitive function was assessed using Bangla Adaptation of Mini-Mental State Examination (BAMSE). Educational level and occupational complexity were used as proxy indicators for calculating cognitive reserve. RESULTS: Of the 370 elderlies interviewed (mean age = 68.9 years), cognitive function was abnormal in 13.5%. The cognitive function had a significant inverse relationship with depression symptoms, loneliness, hypertension, anemia, and basic activities of daily living. There was a significant difference in the cognitive reserve of the elderly with normal and abnormal cognitive function (mean 33.7 and 26.8, respectively). In the presence of covariates like sleep quality, depression, hypertension, and hemoglobin levels, the effect of age on cognitive function had a significant mediation influence of cognitive reserve − total effect = −0.2349; 95% CI = (−0.2972 to −0.1725) and direct effect = −0.2583; 95% CI = (−0.3172 to −0.1994). CONCLUSION: The quantum of effect of the age on cognitive function decreases with good cognitive reserve as a cognitive reserve has a significant mediation effect on the relationship between age and cognitive function.