Epidemiologic outcomes associated with NHLBI guideline-recommended pharmacotherapy among patients with persistent asthma in the Texas Medicaid program

Asthma-related morbidity and mortality rates have risen over the past 20 years, and asthma continues to be a major public health problem in the United States today. The National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health recommends the use of inhaled anti-inflammatory pharmacotherapy for first-line treatment of patients with persistent asthma. The NHLBI also recommends that patients with persistent asthma should seek routine outpatient asthma care at least once every six months. The objectives of the study were: to investigate trends in prescription and medical services utilization among patients with persistent asthma in the Texas Medicaid Program; and to investigate the relationship between the use of inhaled anti-inflammatory medications and asthmarelated morbid events (emergency department (ED), hospital, and life-threatening events). Using criteria established by the National Committee for Quality Assurance, there were 78,078 recipients in the Texas Medicaid Program who were identified with persistent asthma between September 1, 1997 and July 25, 2001. The rates of persistent asthma in the Texas Medicaid Program slightly increased from 21.6 per 1,000 recipients in 1998 to 23.9 per 1,000 recipients in 2000. Analyzing Texas Medicaid prescription and medical claims from calendar years 1998, 1999, and 2000 showed that the highest rates of persistent asthma occurred among children aged six to 14 years old, males, and blacks. Children, ma les, and blacks also had the highest rates of asthma-related medical services utilization. There was a low percentage of recipients (12.4% to 16.0%) who received routine outpatient care during calendar years 1998, 1999, and 2000. About half of the recipients had at least one prescription claim for an inhaled anti-inflammatory medication each year. Recipients treated with inhaled anti-inflammatory agents utilized outpatient services at a higher rate and emergency department services at a lower rate compared to recipients treated otherwise. Results from this study showed that recipients introduced to inhaled antiinflammatory therapy within 100 days following an asthma-related ED visit or hospitalization, compared to those not treated with inhaled anti-inflammatory agents, had a lower risk of subsequent ED or hospital events for up to at least one year. There was no difference in the odds of experiencing an asthma-related lifethreatening event between users and non-users of inhaled anti-inflammatory therapies. It appears that comparator groups in this study differed in disease severity. Future research should include objective clinical data to verify a diagnosis of persistent asthma, and accurately classify disease severity.