Chronic Obstructive Pulmonary Disease Prevalence and Health-Related Quality of Life in South Carolina

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a leading, yet under-recognized cause of morbidity and mortality in the United States. Despite the prevalence of well-established risk factors for COPD, reliable state-specific COPD prevalence estimates across population subgroups and state-level information on the impact of COPD on health-related quality of life (HRQOL) are sparse. To fill this gap, we investigated how COPD affects different population subgroups and examined associations between COPD and four core measures of HRQOL among participants (n = 12,845) of the 2011 South Carolina Behavior Risk Factor Surveillance System (BRFSS).

METHODS: COPD prevalence rates were age-standardized to the 2000 standard US population; except those associated with specific age-groups. Multivariate logistic regression models were used to estimate odds ratios (OR’s) and 95% confidence intervals (95% CI) for HRQOL, adjusting for race, age, gender, education, income, smoking status, and health insurance coverage.

RESULTS:  The overall age-adjusted prevalence of self-reported COPD among community-dwelling adults (aged ≥ 18 years) in South Carolina in 2011 was 7.1% [standard error (SE) ± 0.31].  As expected,  prevalence of self-reported COPD increased with age, ranging from as low as 3.9 (SE ± 0.33) among those 18-44 years to as high as 12.9 (SE ± 0.51) among those 65 years and older. Females had higher prevalence of self-reported COPD (8.9%, SE ± 0.51 ) than males (5.3%, SE ± 0.37). Self-reported COPD prevalence was highest among current smokers (15.9%, SE ± 0.75), while former smokers also had higher prevalence of self-reported COPD (7.9%, SE ± 0.52) than non-smokers (3.6%, SE ± 0.22). Prevalence of self-reported COPD decreased markedly at higher levels of education and income. However, self-reported COPD prevalence did not differ by race and health insurance coverage. Compared to community-dwelling adults without COPD, those with COPD were more likely to report fair/poor general health status (OR: 3.97, 95% CI = 3.13-5.03), 14 or more physically unhealthy days (OR: 2.10, 95% CI = 1.57-2.81), 14 or more mentally unhealthy days (OR: 1.72, 95% CI = 1.21-2.43), and 14 or more days of activity limitation (OR: 2.22, 95% CI = 1.53-3.22).

CONCLUSIONS:  These results indicate that COPD is a highly prevalent disease in South Carolina, and associated with poorer HRQOL.  Future work aimed at reducing risk factors, such as smoking cessation policies and programs, increasing early detection, and improving access to appropriate medical treatments may reduce the disease prevalence and improve HRQOL among those living with the disease.