Reduced lung function is associated with type 2 diabetes (T2D), but there are limited data in East Asian populations on the relationship between them. For this reason, this study investigated the longitudinal relationship of lung function with incident T2D in Korean adults.

The study included 7583 non-diabetic adults aged 40–69 years from the Korean Genome and Epidemiology Study. Participants were divided into four groups according to gender-specific quartiles (Q1–Q4) of %PFVC and %PFEV₁. Also, HRs with 95% CIs for incident T2D were prospectively analyzed as per American Diabetes Association criteria using multivariate Cox proportional-hazards regression models.

During a 12-year follow-up, 1403 (18.5%) participants presented with newly developed T2D. HRs (95% CIs) of incident T2D in Q1 vs. Q4 (reference) of %PFVC were 1.67 (1.35–2.07) for men and 1.77 (1.39–2.24) for women and, of %PFEV₁, 1.58 (1.28–1.95) for men and 1.61 (1.27–2.03) for women, after adjusting for age, waist circumference, smoking status, alcohol intake, regular exercise, education levels, monthly household income, family history of diabetes, HOMA-IR, triglycerides, HDL cholesterol and high-sensitivity C-reactive protein levels.

Reduced lung function precedes and significantly predicts the future development of T2D independently of obesity, smoking and inflammation in community-dwelling middle-aged and elderly people.