Sex differences in the association between body mass index and quality of life among Korean older adults; evidence from a Community Health Survey in South Korea

Background: The high prevalence of underweight individuals is an important issue that has become increasingly common. Therefore, this study investigated the association between body mass index (BMI) and health-related quality of life (HRQoL) among Korean older adults using a nationwide population-based survey. Methods: Data from the 2021 Community Health Survey were used for this study. The study population was a total of 70,700 respondents. HRQoL was assessed using the EuroQoL health-related quality of life scale. Multiple logistic regression was applied to analyze the ORs for moderate or severe problems in the five EQ-5D dimensions. In addition, we performed multiple linear regression to identify the association between the total EQ-5D score and BMI after adjusting for age, marital status, income, education, health behaviors, and the presence of diabetes or hypertension. Results: Of the participants, 4.3% were underweight (3.3% of men and 5.1% of women). Being underweight is associated with poor HRQoL in both men and women. The relationship between obesity and HRQoL varied by sex. Men with pre-obesity and obesity were less likely to have “moderate or severe” problems in all EQ-5D dimensions, excluding mobility. However, women with obesity were more likely to have “moderate or severe” problems across EQ-5D dimensions, excluding anxiety/depression. Conclusions: Being underweight is associated with poor HRQoL among Korean older adults. Policy attention must be directed toward maintaining proper weight and promoting nutritional health at older ages, given that the number of older adults is expected to continue to increase.