Chronic obstructive pulmonary disease and subsequent overall and lung cancer mortality in low-income adults

PLoS One. 2015 Mar 26;10(3):e0121805. doi: 10.1371/journal.pone.0121805. eCollection 2015.

Abstract

Background: Chronic obstructive pulmonary disease (COPD) is a known risk factor for lung cancer and a leading cause of mortality in the U.S., but its impact may not be fully appreciated, especially among low-income populations in the southeast where COPD prevalence and lung cancer incidence are elevated.

Methods: We conducted a prospective study among 26,927 low-income adults age 40-79 in the Southern Community Cohort Study who had a Center for Medicare and Medicaid Services (CMS) encounter prior to enrollment and were followed for a median of over 6 years. Using a validated algorithm for assessing COPD from CMS claims data, we estimated COPD prevalence and potential misreporting. From Cox proportional hazard models, we computed overall and lung cancer-specific mortality according to COPD status.

Results: The overall prevalence of CMS-diagnosed COPD was 16%, but was twice as high among whites as blacks. Only 35% of these individuals, however, self-reported having COPD, with underreporting significantly greater for blacks than whites. Smoking-adjusted all-cause mortality was increased by 1.7-fold and lung cancer mortality by 2.3-fold among those with a CMS COPD diagnosis, with similar patterns in blacks and whites, but no excess was found among those self-reporting COPD and without CMS confirmation.

Conclusion: The prevalence of COPD in this low-income population may be greater than previously recognized and misreporting is common. COPD is associated with elevated lung cancer mortality, even among those not self-reporting the condition.

Publication types

  • Research Support, American Recovery and Reinvestment Act
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • African Continental Ancestry Group / statistics & numerical data
  • Aged
  • Cohort Studies
  • European Continental Ancestry Group / statistics & numerical data
  • Female
  • Humans
  • Lung Neoplasms / economics*
  • Lung Neoplasms / mortality*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Poverty / statistics & numerical data*
  • Proportional Hazards Models
  • Pulmonary Disease, Chronic Obstructive / complications*
  • Risk Factors
  • United States / epidemiology