LAUSR

Objectives Epidemiological studies suggested the evidence that coffee consumption decreased risk of type 2 diabetes. Recently, Japanese genome-wide association studies (GWAS) of coffee consumption has identified rs2074356 (G > A) at 12q24.12-13 in HECTD4. This study aims to examine the associations of habitual coffee consumption with prediabetes and type 2 diabetes, and whether this association is modified by rs2074356 variant in Korean adults. Methods A total of 4010 participants (1890 men and 2120 women) who had genetic information from Korea Association REsource (KARE) study were included. Habitual coffee consumption was assessed through a food frequency questionnaire and categorized into five categories (non-consumers, <1 cup/day and ≥1 cups/day of black coffee, and <1 cup/day and ≥1 cups/day of sugared coffee). Incident prediabetes or type 2 diabetes were defined according to the self-report of physician-diagnosis, oral glucose tolerance test (OGTT) or hemoglobin A1c (HbA1c) test. Multivariable logistic regression models were used to calculate odds ratio (OR)s and 95% confidence interval (CI)s. Results A total of 2916 participants (72.7%) have developed prediabetes during a follow-up of 15 years. We found that black coffee consumption lowered risk of prediabetes and type 2 diabetes combined among men and women combined (OR = 0.63; 95% CI = 0.44-0.91 for ≥1 cups/day black coffee vs. non-consumers). When we separated men and women, compared with non-consumers, ORs (95% CIs) for ≥1 cups/day of black coffee were 0.50 (0.27-0.93) among men and 0.72 (0.45-1.14) among women and ORs (95% CIs) for ≥1 cups/day of sugared coffee were 1.41 (0.91-2.18) among men and 1.12 (0.80-1.58) among women. We observed a suggestive difference by rs2074356 (GG vs. AG + AA). Compared with non-consumers, participants with AG + AA genotypes consumed ≥ 1 cups/day of black coffee had a 60% lower risk of prediabetes and type 2 diabetes combined (95% CI 0.20-0.78), but we found a weaker association among those with GG genotype (OR = 0.81; 95% CI = 0.51-1.28). Conclusions We observed an inverse association between black coffee consumption and prediabetes and type 2 diabetes combined in Korean population. This association was more pronounced among carriers of minor allele of HECTD4 rs2074356 (AG/AA). Funding Sources None.