RESUMO
PURPOSE: Body mass index (BMI) is directly associated with employment status. Our longitudinal prospective study is aimed at ascertaining whether work ability index (WAI) 4 years after surgery remains improved, such as 1 year after surgery, or changes and whether socio-demographic or psycho-social factors influence changes in work ability. MATERIALS AND METHODS: 197 bariatric surgery candidates were recruited. Data on demographic and psycho-social characteristics were collected prior to surgery (t1) and at 6 (t2), 12 (t3), and 48 months (t4). Change effects over time in the WAI and BMI were investigated using a repeated-measures analysis of variance (ANOVA). A hierarchical multiple regression analysis was calculated to predict socio-demographic and psychosocial characteristics at t1 on WAI at t4. RESULTS: Not only a significant increase in WAI was observed between t1 and t2 and between t3 and t4 but also a significant decrease between t2 and t4. BMI reduction was significant between t1 and t2 and t3 and t4, respectively. There was no significant interaction effect of BMI reduction 4 years after surgery on decreased work ability from t2 to t4. The hierarchical multiple regression analysis revealed an association of WAI scores at t1 on WAI scores at t4 only. CONCLUSIONS: Work ability 4 years after surgery remained significantly improved compared to the values at t1-t3 assessment. Since work ability was the only predictor at t1, findings might indicate the use of psycho-social measures post bariatric surgery to increase work ability. There was no association between work ability and other socio-demographic or psycho-social factors.