The relation between self-reported body weight and health-related quality of life: a cross-sectional study in Japan.

ABSTRACT

BACKGROUND: Whilst being obese is associated with increased mortality, less is known about the relationship between body weight and health-related quality of life (HRQOL). We aimed to examine this relationship in the general Japanese population, focusing on both underweight and overweight individuals. METHODS: We cross sectionally analyzed data from the Health Diary Study, which surveyed health-related behavior in a nationally quasi-representative sample from 2003. HRQOL was measured using the Short Form-8 Health Survey. Body mass index (BMI) was calculated from self-reported height and weight values. We compared differences in HRQOL in people with normal BMI (18.5-24.9) with those with underweight (<18.5), overweight (25-29.9) or obese (≥30) BMIs. RESULTS: Among a population-weighted random sample (5387 households), 1857 households (34.5%) agreed to participate. Of the targeted sample population (3658 people), 3477 responded (95.1%). Of 2453 people (age ≥18 years), we analyzed data from 2399 people. After adjusting for age, sex and status of chronic conditions, we found that being overweight was correlated with impaired physical HRQOL [coefficient-0.96 (95% confidence interval (CI) -1.73, -0.20)] but not with mental HRQOL [coefficient -0.17 (95% CI -0.50, 0.95)]. CONCLUSIONS: Although the differences were small, being overweight was correlated with impaired physical HRQOL but not with mental HRQOL.