Geographic isolation and the risk for chronic obstructive pulmonary disease-related mortality: a cohort study.

BACKGROUND Little is known about the possible differences in outcomes between patients with chronic obstructive pulmonary disease (COPD) who live in rural areas and those who live in urban areas of the United States. OBJECTIVE To determine whether COPD-related mortality is higher in persons living in rural areas, and to assess whether hospital characteristics influence any observed associations. DESIGN Retrospective cohort study. SETTING 129 acute care Veterans Affairs hospitals. PATIENTS Hospitalized patients with a COPD exacerbation. MEASUREMENTS Patient rurality (primary exposure); 30-day mortality (primary outcome); and hospital volume and hospital rurality, defined as the mean proportion of hospital admissions coming from rural areas (secondary exposures). RESULTS 18,809 patients (71% of the study population) lived in urban areas, 5671 (21%) in rural areas, and 1919 (7%) in isolated rural areas. Mortality was increased in patients living in isolated rural areas compared with urban areas (5.0% vs. 3.8%; P = 0.002). The increase in mortality associated with living in an isolated rural area persisted after adjustment for patient characteristics and hospital rurality and volume (odds ratio [OR], 1.42 [95% CI, 1.07 to 1.89]; P = 0.016). Adjusted mortality did not seem to be higher in patients living in nonisolated rural areas (OR, 1.09 [CI, 0.90 to 1.32]; P = 0.47). Results were unchanged in analyses assessing the influence of an omitted confounder on estimates. LIMITATIONS The study population was limited to mostly male inpatients who were veterans. Results were based on administrative data. CONCLUSION Patients with COPD living in isolated rural areas of the United States seem to be at greater risk for COPD exacerbation-related mortality than those living in urban areas, independent of hospital rurality and volume. Mortality was not increased for patients living in nonisolated rural areas. PRIMARY FUNDING SOURCE U.S. Department of Veterans Affairs.