GPT and chronic obstructive pulmonary disease: The univariable and multivariable Cox regression analyses revealed that old age, male sex, smoking, comorbidities, lack of exercise, low systolic blood pressure, and lower ALT levels were significant risk factors for COPD development [hazard ratio (HR): 0.998, 95% confidence interval (CI): 0.997–0.999, P < 0.0001; Supplementary Table 1].