Influence of body shape on health-related quality of life in Korean adults: The mediating effect of self-rated health

A Body Shape Index (ABSI) predicts mortality independent of body mass index and had a negative relationship with self-rated health (SRH), which had a positive effect on the EuroQol (EQ)-5D index. This study aimed to investigate the relationship between ABSI and the EQ-5D index and to verify the mediating effect of SRH in Korean adults. This study included 13,381 participants aged ≥20 years from the 7th (2016-2018) Korean National Health and Nutrition Examination Survey (KNHANES). The participants were classified into tertile groups based on the ABSI (T1, T2, and T3 groups). Demographic characteristics, health-related factors, ABSI, SRH, and EQ-5D scores were evaluated. Women (p<0.001), rural areas (p<0.001), married persons (p<0.001), low education level (p<0.001), low income (p<0.001), and older age (p<0.001) were higher in the T3 group. The monthly drinking (p<0.001), current smoking (p<0.001), and mental stress rates (p<0.001) were the highest in the T1 group. The overall average SRH scores and EQ-5D index were 3.08 points and 0.94 points, respectively. ABSI and SRH (r = -0.161, p<0.001) and ABSI and EQ-5D (r = -0.229, p<0.001) showed a negative correlation. However, SRH and EQ-5D scores (r = 0.433, p<0.001) were positively correlated. The overall effect of the independent variable ABSI on the dependent variable EQ-5D was -0.959. SRH partially mediated the effect of ABSI on EQ-5D (indirect effect coefficient = –0.200). These results can be used as basic data to develop strategies and programs to improve health-related quality of life by adjusting ABSI and SRH.