Geographic variation in asthma admission rates across hospital referral regions in Texas: An analysis of private insurance population between 2008 and 2011

Objectives: To explore the geographic variation in asthma admission rates among private insurance population between 2008 and 2011 Methods: All Hospital admissions for asthma during the period of 2008 to 2011 were identified from the Blue Cross Blue Shield of Texas claims data using criteria specified in the Agency for Health Care Research and Quality's prevention quality indicators and pediatric quality indicators for asthma. BCBS covered lives by Hospital Referral Region (HRR) were extracted to calculate the HRR asthma admission rate. Index of variation (each HRR admission rate compare to overall Texas means) and coefficients of variation (CV; standard deviations from the Texas means) were calculated to examine the variation in asthma admission rate. Results: 6,651 asthma admissions were identified. Texas overall asthma admission rates were 51.38(2008), 53.34(2009), 43.35(2010), and 39.83(2011) admissions per 100,000 beneficiaries. Adult (18 years and older) admission rate were 44.31(2008), 42.26(2009), 36.77(2010), and 32.99(2011) admissions per 100,000 adult beneficiaries while the Pediatric (2-18 years old) admission rate were 75.98(2008), 95.04(2009), 67.53(2010), and 65.36(2011) admissions per 100,000 pediatric beneficiaries. Results indicated that variation in pediatric asthma admission rate (CV=0.31(2008), 0.46(2009), 0.50(2010), 0.30(2011)) is higher compare to adult asthma admission rate (CV=0.22(2008), 0.25(2009), 0.24(2010), 0.24(2011)). Conclusions: Substantial variations in asthma admission rates were found among HRRs in both adult and pediatric Texas population. Variations were found to be higher in pediatric population compare to adult population. Further investigation of factors that contribute to this variation will provide insights for better policies and programs that intervene on preventable asthma admission.