Race, income, urbanicity, and asthma hospitalization in California: a small area analysis

Abstract

Study objectives: To explicate the interrelationship between asthma hospitalization and race/ethnicity and income.

Design: Small area ecologic analysis using census and administrative data.

Setting and participants: All asthma hospitalizations in California were identified using the 1993 California Hospital Discharge file. Small area analyses of Los Angeles (LA) were compared with published rates in New York City (NYC).

Results: In 1993, the age-adjusted asthma hospitalization rate in California for nonelderly blacks was 42.5/10,000-approximately four times higher than other populations. Black rates remained fourfold higher after stratification by age, income, and urbanicity. Multivariate analyses suggest that the association between black race and asthma hospitalization is independent of income. Regardless of race, children and persons living in poverty were at increased risk for asthma hospitalization. Urbanicity was not a predictor for asthma hospitalization. Overall, asthma hospitalization rates in NYC were 2.8 times higher compared with rates in LA; while rates were similar among blacks (60 vs 40/10,000, respectively), Puerto Rican Hispanics in NYC had dramatically higher rates compared with Mexican Hispanics in LA (63 vs 14/10,000, respectively).

Conclusions: After controlling for socioeconomic status, notable differences in asthma hospitalization by race and ethnicity persist. The reasons for the significantly elevated risk of asthma morbidity among blacks remain unclear.