Cognitive impairment and depressive symptoms: effects on functional disability, falls, hospitalization, and polypharmacy in a longitudinal follow-up

Introduction: The ageing process is associated with a higher prevalence of depression and cognitive impairment, negatively affecting health. Objective: Analyse the effects of cognitive impairment and depressive symptoms on the risk of functional disability, falls, hospitalisation, and polypharmacy in a two-year follow-up. Methods: Longitudinal study, developed with 200 participants over 45 years old from primary healthcare centres in Três Lagoas, Mato Grosso do Sul, Brazil. The participants were initially evaluated using cognitive and depressive symptoms screening instruments. After two years, functional disability (instrumental activities of daily living), falls, hospitalisation, and polypharmacy were evaluated. Multinomial regression models were performed to assess the effects of cognitive impairment and depressive symptoms on outcomes. Results: 38.5% of the participants had a cognitive impairment, and 55.0% had depressive symptoms. Cognitive impairment at baseline was associated with an increased risk of disability to shopping (OR=2.946), performing housework (OR=2.196), and managing finances (OR=3.488). Depressive symptoms were related to a higher risk of dependence on traveling (OR=1.614), administering medications (OR=5.745), managing finances (OR=2.876), falls (OR=1.960), and polypharmacy (OR=2.464). Participants with the two associated conditions were at higher risk of dependence on using the telephone (OR=2.701), travelling (OR=2.177), shopping (OR=2.890), administering medications (OR=4.773), and managing finances (OR=3.799). Conclusion: Cognitive impairment was associated with dependence in three activities after two years. Depressive symptoms were related to a greater risk of dependence in three activities, falls, and polypharmacy. The cumulative effect of cognitive impairment and depressive symptoms negatively influenced the performance in five instrumental activities of daily living.