Obesity is associated with postural balance on unstable surfaces but not with fear of falling in older adults

Background: There are inconsistent findings regarding the relationship between body mass index (BMI), fear of falling and body balance, especially on unstable surfaces. Objectives: To investigate whether obesity is associated with worse postural balance and fear of falling in older adults. Methods: A cross-sectional study was conducted with 201 older adults, classified as normal weight, overweight, or obese according to BMI. Postural balance was evaluated on stable and unstable surfaces on the Biodex Balance System platform under three visual conditions: with and without visual feedback and with eyes closed. Fear of falling was identified by a dichotomous question and the Falls Efficacy Scale. These data were compared between groups and included in adjusted multiple linear regression analysis. Results: The study showed no significant differences (p > 0.05) in body oscillations on a stable surface between the three groups. On an unstable surface, the obese older adults exhibited body oscillations from 0.61 degrees [95% CI 0.07, 1.30] to 1.63 degrees [95% CI 0.84, 2.41] greater than those with normal weight in the three visual conditions. The obese older adults also displayed larger mediolateral oscillations with visual feedback (mean difference: 0.50 degrees [95% CI 0.01, 0.98]) as well as greater global oscillations without visual feedback (mean difference of 0.82 degrees [95% CI 0.18, 1.81]) and with progressive instability (mean difference: 0.80 degrees [95% CI 0.05, 1.66]) than the overweight older adults. BMI explained from 6 to 12% of body swings investigated on unstable surface. Obesity was not associated with fear of falling. Conclusion: Obesity was associated with reduced postural stability on unstable surfaces but not with fear of falling in older adults. (C) 2020 Associacao Brasileira de Pesquisa e Pos-Graduacao em Fisioterapia. Published by Elsevier Editora Ltda. All rights reserved.