Association Between High-Density Lipoprotein Cholesterol and Type 2 Diabetes Mellitus Among Chinese: The Beijing Longitudinal Study of Aging

Abstract Background: Contradictory conclusions of association between high-density lipoprotein cholesterol (HDL-C) levels and type 2 diabetes mellitus (T2DM) were reported in different populations. This study aimed to clarify the effect of HDL-C on the risk of T2DM incidence using a cohort lasting for 25-year follow-up.Methods: This study included 1462 community residents aged 55 or above, excluding subjects with diabetes at baseline. Incident cases of T2DM were ascertained by self-reported T2DM or fasting plasma glucose testing. The data were collected in nine surveys held between the years 1992 to 2017. Cox regression and the Fine-Gray model were applied to evaluate the relationship between HDL-C levels and the risk of T2DM incidence.Results: 120 participants developed new diabetes during follow-up period. There was a significant negative association between HDL-C levels and the risk of newly on-set T2DM. The incidences of T2DM decreased with the increasing quartile ranges of HDL-C levels, which were 12.60, 9.70, 5.38 and 5.22 per 1000 person-years, respectively. The adjusted hazard ratios (HRs) and 95% confidence intervals were 0.78 (0.50-1.23), 0.51 (0.29-0.90) and 0.47 (0.26-0.84) for subjects with baseline HDL-C levels in ranges of 1.15-1.39, 1.40-1.69 and ≥ 1.70 mmol/L, compared with ones in the range of < 1.15 mmol/L. Similar decreased HRs of T2DM for elevated HDL-C levels were observed in time-dependent Cox regression and other sensitivity analyses.Conclusion: Higher HDL-C levels were independently related to the lower risk of the newly-onset T2DM among the elderly in China.