Publications

BACKGROUND

Morbidity from asthma disproportionately affects black people. Whether this excess morbidity is fully explained by differences in asthma severity, access to care, or socioeconomic status (SES) is unknown.

METHODS

We assessed whether there were racial disparities in asthma management and outcomes in a managed care organization that provides uniform access to health care and then determined to what degree these disparities were explained by differences in SES, asthma severity, and asthma management. We prospectively studied 678 patients from a large, integrated health care delivery system. Patients who had been hospitalized for asthma were interviewed after discharge to ascertain information about asthma history, health status, and SES. Small-area socioeconomic data were ascertained by means of geocoding and linkage to the US Census 2000. Patients were followed up for subsequent emergency department (ED) visits or hospitalizations (median follow-up, 1.9 years).

RESULTS

Black race was associated with a higher risk of ED visits (hazard ratio [HR], 1.93; 95% confidence interval [CI], 1.39-2.66) and hospitalizations (HR, 1.89; 95% CI, 1.30-2.76). This finding persisted after adjusting for SES and differences in asthma therapy (adjusted HR for ED visits, 1.73; 95% CI, 1.07-2.81; and adjusted HR for hospitalizations, 2.01; 95% CI, 1.33-3.02).

CONCLUSIONS

Even in a health care setting that provides uniform access to care, black race was associated with worse asthma outcomes, including a greater risk of ED visits and hospitalizations. This association was not explained by differences in SES, asthma severity, or asthma therapy. These findings suggest that genetic differences may underlie these racial disparities.

We investigated whether perceived neighborhood problems (NP) predicted changes over a 2-year period in asthma-specific quality of life (QOL), physical functioning (PF), and depressive symptomology (DEP) in a longitudinal cohort of 340 adults with asthma. There is a threshold and plateau effect between NP and PF, such that NP do not affect changes in PF until the problems reach the level of Quartile 3. People who had NP scores in Quartile 3 had lower PF compared to people who reported NP in Quartiles 1 or 2 (mean difference -3.09). High NP also predicted over two-fold odds of high DEP (Center for Epidemiological Studies Depression [CES-D] score > or = 16) at follow-up (odds ratio=2.34; 95% confidence interval: 1.09-5.00). NP did not predict decline in QOL. Analyses adjusted for demographics, asthma severity, and baseline value of the health outcome.

Common polymorphisms in the CRP gene are associated with plasma CRP levels in population-based studies, but associations with age-related events are uncertain. A previous study of CRP haplotypes in older adults was broadened to include longevity and cause-specific mortality (all-cause, noncardiovascular (non-CV), and cardiovascular (CV)). Common haplotypes were inferred from four tagSNPs in 4512 whites and five tagSNPs in 812 blacks from the Cardiovascular Health Study, a longitudinal cohort of adults over age 65. Exploratory analyses addressed early versus late mortality. CRP haplotypes were not associated with all-cause mortality or longevity overall in either population, but associations with all-cause mortality differed during early and late periods. In blacks, the haplotype tagged by 3872A (rs1205) was associated with increased risk of non-CV mortality, relative to other haplotypes (adjusted hazard ratio for each additional copy: 1.42, 95% CI: 1.07, 1.87). Relative to other haplotypes, this haplotype was associated with decreased risk of early but not decreased risk of late CV mortality in blacks; among whites, a haplotype tagged by 2667C (rs1800947) gave similar but nonsignificant findings. If confirmed, CRP genetic variants may be weakly associated with CV and non-CV mortality in older adults, particularly in self-identified blacks.