The value of apolipoprotein B/A1 ratio in the diagnosis of metabolic syndrome in a Korean population.

The ratio of apolipoprotein B (apoB) to apolipoprotein A1 (apoA1) has been reported to be associated with the metabolic syndrome (MetS). However, the optimal cut-off value of apoB/A1 ratio for detecting subjects with MetS has remained undetermined. In the present study, we aimed to investigate whether apoB/A1 ratio can be an indicator of MetS and to determine the optimal cut-off value of apoB/A1 ratio in detecting subjects with MetS in a Korean population. This cross-sectional study was conducted at the Asan Medical Center, Seoul, Republic of Korea. We collected the data of 10,940 subjects who participated in a routine health screening examination regarding conventional risk factors and serum levels of apoB and apoA1. The odds for MetS were significantly higher in the highest compared with the lowest apoB/A1 ratio quartiles, after adjustment for confounding variables, in both men [odds ratio (OR) = 4·07, 95% CI = 3·42-4·84] and women (OR = 8·41, 95% CI = 5·85-12·08). The optimal apoB/A1 ratio cut-off value for the detection of MetS was 0·65, which had a sensitivity of 63·5% and a specificity of 61·3% (area under the curve = 0·67, 95% CI = 0·66-0·68, P < 0·001) in men and 0·62, which had a sensitivity of 67·9% and a specificity of 61·9% (area under the curve = 0·70, 95% CI = 0·69-0·71, P < 0·001) in women. These results suggest that apoB/A1 ratio is independently associated with MetS and that an apoB/A1 ratio >0·65 in men and 0·62 in women is a marker of MetS independent from conventional risk factors.