Understanding temporal relationships between depression, falls, and physical activity in a cohort of post-hospitalized older adults - a breakthrough or a conundrum?

Background: Clinical depression affects approximately 15% of community-dwelling older adults, of which half of these cases present in later life. Falls and depressive symptoms are thought to co-exist, while physical activity may protect an older adult from developing depressive symptoms. This study investigates the temporal relationships between depressive symptoms, falls, and participation in physical activities amongst older adults recently discharged following extended hospitalization. Methods: A prospective cohort study in which 311 older adults surveyed prior to hospital discharge were assessed monthly post-discharge for six months. N = 218 completed the six-month follow-up. Participants were recruited from hospitals in Melbourne, Australia. The survey instrument used was designed based on Fiske's behavioral model depicting onset and maintenance of depression. The baseline survey collected data on self-reported falls, physical activity levels, and depressive symptoms. The monthly follow-up surveys repeated measurement of these outcomes. Results: At any assessment point, falls were positively associated with depressive symptoms; depressive symptoms were negatively associated with physical activity levels; and, physical activity levels were negatively associated with falls. When compared with data in the subsequent assessment point, depressive symptoms were positively associated with falls reported over the next month (unadjusted OR: 1.20 (1.12, 1.28)), and physical activity levels were negatively associated with falls reported over the next month (unadjusted OR: 0.97 (0.96, 0.99) household and recreational), both indicating a temporal relationship. Conclusion: Falls, physical activity, and depressive symptoms were inter-associated, and depressive symptoms and low physical activity levels preceded falls. Clear strategies for management of these interconnected problems remain elusive.