Elevated C-reactive protein and mortality risk among COPD patients

Abstract

Abstract Background Chronic obstructive pulmonary disease (COPD) is a progressive disease associated with autoimmune systemic inflammation. The evidence on the role of C-reactive protein (-CRP) in predicting mortality among people with COPD remains mixed. Methods Data from the National Health and Nutrition Examination Survey (1999–2010) were linked with mortality files up to December 31st, 2019, from the National Death Index. Adults ages 20 years or older were included in the analytic sample to assess the relationship between physician-diagnosed self-reported COPD and mortality based on blood CRP levels. Multivariate complex samples Cox regression analyses were conducted to determine the hazards ratios (with 95% CI). Results A total of 30,669 individuals comprised of the final sample with 2215 deaths observed upon follow-up for an average of 10.2 years. Compared to individuals without COPD or elevated CRP, individuals with COPD but without elevated CRP (HR = 1.25, 95% CI = 0.97–1.61) did not have a significantly higher risk of mortality. However, those with both COPD and elevated CRP had a significantly higher risk of mortality (HR = 2.70, 95% CI = 1.08–6.81). Age, health insurance status, and a history of comorbidities modified these relationships. Conclusions Biomarkers such as CRP continue to show promise for long-term COPD-related outcomes. Additional prospective assessments of individuals with airway obstruction are warranted to understand if CRP levels predict the occurrence or worsening of COPD and if those relate to long-term health outcomes.