Thresholds for postprandial hyperglycemia and hypertriglyceridemia associated with increased mortality risk in type 2 diabetes patients: A real‐world longitudinal study

AIMS/INTRODUCTION: To identify thresholds for postprandial hyperglycemia and hypertriglyceridemia predictive of all‐cause mortality in patients with type 2 diabetes. MATERIALS AND METHODS: A total of 1,928 patients with type 2 diabetes visited our clinic for the first time from 1995 to 1999 and were followed up for ≥1 year. During the first year, 2‐h post‐breakfast blood glucose (2h‐BG) levels were measured in 1,122 patients (BG cohort) and postprandial serum triglyceride (ppTG) levels were measured in 1,826 patients (TG cohort). Patients were retrospectively followed until 2017 and administered questionnaires. Associations between 2h‐BG and ppTG levels and mortality risk were assessed by the multivariate Cox regression analysis. RESULTS: Over of 17,429 person‐years, 162 deaths occurred in the BG cohort, and over 28,026 person‐years, 253 deaths occurred in the TG cohort. Hazard ratios (HRs) with 95% confidence intervals for all‐cause mortality per 1‐standard deviation increases in 2h‐BG and ppTG were 1.34 (1.08–1.67) and 1.24 (1.06–1.45), respectively. HRs showed increasing trends across quintiles of 2h‐BG (P = 0.034) and ppTG (P = 0.007). The HR was significantly elevated (2.37, 1.26–4.47) in the fifth quintile of 2h‐BG (≥13.8 mmol/L) compared with the first quintile (<7.0 mmol/L; P = 0.008). The HR was also significantly elevated (1.63, 1.03–2.60) in the fifth quintile of ppTG (≥2.30 mmol/L) compared with the first quintile (<0.91 mmol/L; P = 0.038). CONCLUSIONS: Postprandial hyperglycemia and hypertriglyceridemia were associated with all‐cause mortality in patients with type 2 diabetes. We propose thresholds of 13.8 mmol/L 2h‐BG and 2.30 mmol/L ppTG to identify patients at increased risk of mortality.