Interactions between Subjective Memory Complaint and Cognitive Impairment in an Elderly Indigenous Population in Brazil

INTRODUCTION: This article aimed to analyze the association between subjective memory complaints (SMCs) and cognitive performance in elderly indigenous individuals of the Xukuru do Ororubá ethnicity in Brazil. METHODS: This was a population-based, cross-sectional, analytical survey with data collected from 2015 to 2018. Participants answered questionnaires on sociodemographic and economic aspects, chronic diseases, habits, memory complaint, cognitive assessment, symptoms of depression, and activities of daily living. RESULTS: Overall, 559 older individuals participated in the study (71.3 ± 8.8 years; 55.8% female); the majority were illiterate (67.6%), whereas 24.3% received up to 4 years of education. Regarding clinical aspects, 8.7% reported polypharmacy, 25.6% exercised, 66.9% had hypertension, 15.2% had diabetes, 65% had vision problems, 27.7% had hearing problems, 53.1% had cognitive impairment, and 37.2% had symptoms of depression. The frequency of memory complaints was 54.4% (95% CI: 50.2-58.5). Cognitive deficits were not significantly associated with SMCs (OR, 1.09; 95% CI: 0.76-1.55; p = 0.645). In the multivariate analysis, significance was found for females (OR: 1.49 [95% CI: 1.04-2.14]; p = 0.03), self-reported falling with loss of consciousness (OR: 1.79 [95% CI: 1.08-2.98]; p = 0.025) and falling within the last year (OR: 1.79 [95% CI: 1.19-2.71]; p = 0.005), and visual (OR: 2.33 [95% CI: 1.64-3.33]; p = 0.001) and hearing impairment (OR: 2.44 [95% CI: 1.64-3.62]; p = 0.001), with a two-fold increase in both. Regular exercise was protective with a 36% reduction in chance. The chances of SMCs were higher in individuals with up to 4 years of schooling, but did not increase with more than 5 years of schooling; however, this variable had a small sample size. CONCLUSION: No significant association was found between memory complaints and cognitive decline, but SMCs were associated with several factors, such as female sex, falling, and sensory loss, while exercising was found to be protective.