Abstract
BACKGROUND: The dose-response relationship between glycemic status and lung function has not been thoroughly investigated. We hypothesized that there are continuous and inverse associations between glycemic measures and lung function tests and examined the hypothesis in Japanese adults. METHODS: We cross-sectionally investigated associations of hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) with forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in 3161 adults who participated in a health screening from 2008 to 2011. The study participants included both diabetic and non-diabetic adults. Multiple linear regression analyses were performed to examine the associations. RESULTS: Inverse associations were observed in both sexes, which were attenuated in women after adjustment for multiple variables. A 1% absolute increase in HbA1c was associated with a -52-mL (95% confidence interval [CI] -111 to 8 mL) difference in FVC and a -25-mL (95% CI -75 to 25 mL) difference in FEV1 in women, and a -128-mL (95% CI -163 to -94 mL) difference in FVC and a -73-mL (95% CI -101 to -44 mL) difference in FEV1 in men. A 10-mg/dL increase in FPG was associated with a -11-mL (95% CI -29 to 8 mL) difference in FVC and a -8-mL (95% CI -24 to 7 mL) difference in FEV1 in women, and a -32-mL (95% CI -44 to -21 mL) difference in FVC and a -19-mL (95% CI -28 to -9 mL) difference in FEV1 in men. CONCLUSIONS: Inverse associations between glycemic measures and lung function were observed. Men seem more susceptible to the alteration in FVC and FEV1 than women.