Relationship Between Cognitive Impairment and Postural Stability in Elderly Population

Abstract

Background: Cognitive decline and postural instability frequently coexist in later life, yet the cognitive domains that most strongly influence balance and the added value of integrated cognitive-motor training remain insufficiently defined in older Indian populations. Objective: To examine the relationship between cognitive impairment and postural stability, identify cognitive predictors of balance dysfunction, compare prospective fall incidence, and evaluate an eight-week combined cognitive-balance training programme against balance training alone. Methods: Thirty adults aged 55-75 years were assessed at baseline: 15 with cognitive impairment and 15 cognitively healthy controls. Cognition was evaluated with the Mini-Mental State Examination and Montreal Cognitive Assessment. Postural stability was assessed using the Berg Balance Scale and single-task and dual-task Timed Up and Go tests, with serial subtraction used as the cognitive task. Falls were recorded prospectively for eight weeks. Participants with cognitive impairment were then randomized to combined cognitive-balance training (n=8) or balance-only training (n=7), delivered for 60 minutes, three times weekly, for eight weeks. Group comparisons, correlations, multiple regression, Fisher exact tests, and repeated-measures analysis of variance were used. Results: Compared with cognitively healthy participants, the cognitively impaired group had lower Berg Balance Scale scores (43.2 +/- 6.1 vs 51.8 +/- 3.9; p<0.001; d=1.68), slower single-task Timed Up and Go performance (14.1 +/- 2.7 vs 9.4 +/- 1.6 s; p<0.001; d=2.14), and greater dual-task cost (34.0% +/- 9.5% vs 18.1% +/- 7.2%; p<0.001; d=1.87). Executive function was the only significant independent cognitive predictor of balance (standardized beta=0.51; p<0.001; model R2=0.61). Falls occurred in 40.0% of cognitively impaired and 13.3% of cognitively healthy participants (p=0.109). Combined training produced greater improvement than balance-only training in Berg Balance Scale score (+6.5 vs +2.7 points; time-by-group p<0.001; partial eta-squared=0.58), dual-task Timed Up and Go (-5.2 vs -1.5 s; p<0.001; partial eta-squared=0.55), and dual-task cost (35.2% to 21.4% vs 33.1% to 34.0%; p=0.004). Attendance exceeded 85%, with no dropouts and no serious adverse events. Conclusion: Cognitive impairment, particularly executive dysfunction, is strongly associated with poorer postural stability and greater cognitive-motor interference. Combined cognitive-balance training appears feasible and more effective than balance training alone, although larger controlled trials are required to confirm effects on falls.