Sex Differences in the Association of Youth Body Mass Index to Adult Health-related Quality of Life: The Physical Activity Longitudinal Study

Abstract

Objective: The long-term consequences of youth overweight on adult health-related quality of life (HRQL) have not been documented. This study examines sex differences in the association between youth body mass index (BMI) and adult HRQL. Methods: Subjects included 139 male and 142 female participants aged 7-18 in the 1981 Canada Fitness Survey, followed up in 2002-04. The associations of youth BMI to adult HRQL (SF-36) were examined with bivariate correlations, differences in means and multivariate linear regression analyses. Results: Bivariate analyses revealed positive associations between youth overweight and mental aspects of adult HRQL in females, and weak negative associations with physical aspects, but no significant associations in males. All overweight male and female youth scored the maximum (100) on Role Emotional (RE). In females, compared to healthy weight youth, overweight youth scored 16.0, 13.4, 12.7, and 10.9 points higher on general health (GH), vitality (VT), mental health (MH), and the mental component score (MCS) in adulthood, respectively; a 1 unit increase in youth BMI led to 1.7, 1.5, and 1.4 point increases in adult VT, MH and MCS scores, respectively. Associations were attenuated with the removal of adult BMI from the models, but remained strong for MH and MCS. Conclusions: Overweight in youth did not have a significant negative impact on HRQL two decades later; rather, a positive association was found with mental aspects of adult HRQL in females. Key words: Body mass index; body weight; adolescent obesity; longitudinal studies; mental health; quality of life