Dose-response relationship between fasting plasma glucose and abnormal lung function in a health screening population.

INTRODUCTION: Emerging evidence has suggested complex relationships between glucose metabolism and pulmonary health. However, the nature of the association between fasting plasma glucose (FPG) and lung function remains inadequately characterized. This study aimed to explore this association and provide further evidence. METHODS: This cross-sectional study analyzed data from 6,597 adults in a Chinese health check-up cohort. Lung function was classified into two groups: normal and abnormal. Binary logistic regression was performed to identify the association between FPG and the risk of lung function abnormalities. Restricted cubic splines (RCS) were used to model the FPG-lung function relationship, stratified by sex, age, and BMI. RESULTS: A significant non-linear dose-response relationship (p < 0.05) was found between FPG and lung function abnormalities. RCS analysis showed that increasing FPG from 4.78 to 5.6 mmol/L elevated the risk of lung function abnormalities by 32.0% (OR = 1.32, 95% CI: 1.17-1.49). Gender disparities were evident, with women exhibiting a steeper risk gradient (OR = 1.43 vs. 1.29 in men). Overweight/obese individuals (BMI ≥24 kg/m²) demonstrated a stronger association (OR = 1.45) compared to those of normal weight (OR = 1.21). CONCLUSION: FPG was determined to be an independent predictor of lung function abnormalities, exhibiting a pronounced non-linear dose-response relationship. Maintaining FPG below 5.6 mmol/L may help prevent lung function impairment, underscoring the importance of early glycemic monitoring in predicting lung function.