Serum apolipoprotein B is associated with increased risk of metabolic syndrome among middle-aged and elderly Chinese: A cross-sectional and prospective cohort study

Background: Serum apolipoprotein (apo) B has been associated with an increased risk of atherosclerotic cardiovascular diseases. However, findings on the association between apoB and the risk of metabolic syndrome (MetS) are inconsistent. The purpose of this study was to investigate the association between serum apoB and MetS risk in Chinese population. Methods: A baseline survey was conducted in a population-based cohort of 10 340 adults aged ≥40 years in Shanghai, China, in 2010. A follow-up visit was conducted to assess incident diabetes in 2015. Results: At baseline, 2794 of 10 340 participants (27.02%) had MetS. Serum apoB was significantly associated with an increased risk of prevalent MetS. Multivariable-adjusted odds ratios and 95% confidence intervals (CIs) for quintiles 2-5 compared with quintile 1 (reference) were 1.29 (1.02-1.63), 1.47 (1.18-1.84), 1.32 (1.06-1.65), and 2.02 (1.61-2.51), respectively (P_trend < 0.05). During an average of 5.1 years follow-up, 4627 individuals without MetS at baseline showed a significant association between apoB and the risk of incident MetS. Multivariable-adjusted risk ratios (95% CIs) for subjects in apoB quintiles 2-5 compared with the reference were 1.43 (1.13-1.82), 1.57 (1.25-1.98), 1.74 (1.38-2.18), and 2.07 (1.66-2.58), respectively (P_trend < 0.05). Stratified analysis suggested that the above association was much stronger among normal weight individuals than in those who were overweight or obese. Conclusion: These cross-sectional and prospective studies provide evidence that serum apoB is associated with existing MetS and is a possible predictor of the risk of MetS, especially among normal weight individuals.