Metabolic health, obesity, and prognosis in chronic obstructive pulmonary disease

Abstract

Metabolic syndrome is a common comorbidity in chronic obstructive pulmonary disease (COPD), yet its long-term impact on survival and exacerbations remains controversial. We investigated whether metabolic health status and body mass index (BMI) influence mortality and the rate of acute exacerbations in patients with COPD. We conducted a nationwide multicenter prospective cohort study involving 2,764 patients. Participants were categorized into four phenotypes based on their metabolic health and BMI: metabolically healthy non-obese (MHNO), metabolically healthy obese (MHO), metabolically unhealthy non-obese (MUNO), and metabolically unhealthy obese (MUO). The primary outcome was all-cause mortality, and the secondary outcome was the rate of acute exacerbations. Multivariable Cox proportional hazards and negative binomial regression models were used to identify independent predictors of clinical outcomes. Metabolic phenotypes were not independent predictors of mortality. Instead, baseline lung function and symptom scores demonstrated the most robust predictive power for death. However, a significant association was observed with severe exacerbations. The annual rate of severe exacerbations was markedly lower in the MUO (0.06) and MHO (0.09) groups compared to the MHNO group (0.23) ( P = 0.004). Higher BMI was associated with a lower rate of severe exacerbations regardless of metabolic health status. Higher BMI was associated with a lower rate of severe exacerbations in patients with COPD. Long-term mortality was more strongly associated with baseline lung function and symptom burden than with metabolic health phenotypes.