Self-rated health and life satisfaction among Canadian adults: associations of perceived weight status versus BMI

Abstract

Obesity is associated with impaired health-related quality of life (HRQL). As perceived constructs, self-rated health (SRH) and general life satisfaction (LS) might be more strongly related to perceived weight status than actual weight status. The aim was to assess agreement between perceived weight status and self-reported body mass index (BMI), and to investigate their associations with SRH and LS as indicators of HRQL. Cross-sectional data included 87,545 adults aged 18-65years from the 2005 Canadian Community Health Survey. Agreement between perceived weight status and self-reported BMI was assessed. Prevalence of suboptimal SRH and LS was estimated by perceived weight status and BMI, and adjusted logistic regression used to assess the odds of suboptimal outcomes. Overall agreement between perceived weight status and self-reported BMI was only moderate (females: κ=0.58; males: κ=0.42). The lowest prevalences of suboptimal SRH and LS were in those who reported both a healthy weight BMI and "about right" weight perception. Discordance between perceived weight status and BMI status, and congruence (i.e. perceived weight status=BMI) around underweight or overweight/obese were associated with poorer SRH and LS. For weight perceptions of "about right", BMI status had minimal influence on suboptimal SRH or LS, while perceptions of underweight or overweight were associated with higher odds of suboptimal SRH and LS, independent of BMI. Adults' weight status perceptions often do not agree with their actual weight status, even when self-reported. While both perceived and actual weight status influence self-rated health and life satisfaction, perceptions are more strongly associated with these HRQL indicators and should be considered when informing obesity-targeted policies and programmes.