Process quality measures and asthma exacerbations in the Medicaid population

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1 Process quality measures and asthma exacerbations in the Medicaid population Pierre L. Yong, MD, MPH, a,b,c,d,e and Rachel M. Werner, MD, PhD a,d Philadelphia, Pa Background: Asthma quality assessment often focuses on controller medication use, yet claims-based studies find conflicting associations between this care process and clinical outcomes. Objective: We sought to compare the association between 3 controller-based quality measures and asthma exacerbations to gain better understanding of how processes of care are related to clinical outcomes. Methods: Identifying a cohort of Medicaid beneficiaries with persistent asthma by using Healthcare Effectiveness Data and Information Set (HEDIS) criteria for asthma in in California and New York, we assessed 3 asthma quality metrics in 2002: (1) the current HEDIS measure of at least 1 controller medication filling; (2) at least 4 controller medication prescription fillings; and (3) a controller-to-total asthma medication ratio of at least 0.5. We calculated the odds of having an asthma exacerbation in 2003 as a function of performance on each quality metric, adjusting for race, sex, age, and prior outpatient and acute care use for asthma. Results: Of 90,909 subjects with persistent asthma in California (48.1%) and New York (51.9%), those who obtained at least 1 or at least 4 controller medications had increased likelihood of poor outcomes (adjusted odds ratios, 1.80 [95% CI, ] and 1.44 [95% CI ], respectively). Beneficiaries meeting the controller-to-total asthma medication ratio measure were 23.0% less likely to have exacerbations (adjusted odds ratio, 0.77 [95% CI, ]). Conclusions: A higher controller medication ratio indicated a lower likelihood of asthma exacerbations, whereas assessing the number of controller medication dispensing events was associated with a higher odds of exacerbation. (J Allergy Clin Immunol 2009;124:961-6.) From a the Department of Medicine, Philadelphia Veterans Affairs Medical Center; b the Robert Wood Johnson Clinical Scholars Program, University of Pennsylvania School of Medicine; c the Department of Pulmonary, Allergy and Critical Care, Hospital of the University of Pennsylvania; and d the Leonard Davis Institute of Health Economics and e the Center for Public Health Initiatives, University of Pennsylvania. P. L. Y. is supported by a training grant from the Philadelphia Veterans Affairs Medical Center and the Robert Wood Johnson Clinical Scholars Program. R. M. W is supported in part by a Veterans Affairs HSR&D Career Development Award. The study was supported by pilot grant funding from the Leonard Davis Institute of Health Economics and resources supported by the Clinical and Translational Science Awards (UL1-RR024134). Disclosure of potential conflict of interest: R. M. Werner receives research support from the Institute on Aging, the SGIM Williams Scholar Award, and the Agency for Healthcare Research and Quality and has provided legal consultation/expert witness testimony in cases related to outpatient management of suspected coronary artery disease. P. L. Yong has declared that he has no conflict of interest. Received for publication April 27, 2009; revised July 14, 2009; accepted for publication July 17, Available online September 14, Reprint requests: Pierre L. Yong, MD, MPH, University of Pennsylvania, 1303A Blockley Hall, 423 Guardian Dr, Philadelphia, PA pyong@nas.edu /$00.00 Ó 2009 by Elsevier, Inc. on behalf of the American Academy of Allergy, Asthma & Immunology doi: /j.jaci Key words: Asthma, quality of care, Healthcare Effectiveness Data and Information Set, Medicaid Asthma is a leading chronic illness in the United States, accounting for 1.7 million emergency department (ED) visits, approximately 444,000 hospitalizations, more than 3,500 deaths, and an estimated $19.7 billion in health care costs annually. 1 Among Medicaid enrollees, who account for 16% of the US population, asthma is the ninth most common primary diagnosis for outpatient visits and the tenth most common principal diagnosis for admissions to acute care hospitals. 2 In an attempt to improve health outcomes for patients with asthma and perhaps to control costs, quality of care is frequently measured and often tied to incentives to improve quality. As part of this effort, the National Committee for Quality Assurance (NCQA) developed the Use of Appropriate Medications for People with Asthma metric, part of the Healthcare Effectiveness Data and Information Set (HEDIS), to measure the quality of care provided to asthmatic subjects. 3 This measure quantifies the percentage of health plan members with persistent asthma who are appropriately prescribed a long-term controller medication at least once during a given year. 4 In randomized controlled trials, this process of care predicts fewer ED visits and acute hospitalizations for asthma. 5,6 However, results of effectiveness studies have been contradictory These contradictory and counterintuitive results might reflect problems with the HEDIS metric s definition of quality care. For example, the metric of filling at least 1 controller medication prescription might reflect severity of disease rather than quality of care because subjects with more severe asthma are more likely to obtain controller medication. 10 Alternate process measures for asthma have been proposed to account for this and include the use of 4 or more controller medication canisters per year 14,15 and a controller-to-total asthma medication ratio of 0.5 or greater. 10,16 Process measures such as the HEDIS asthma metric are commonly used in assessing the quality of care provided to asthmatic subjects and are increasingly incorporated into pay-forperformance reimbursement models. 4 However, given the contradictory evidence of the HEDIS measure s correlation with acute care use for asthma, it is unclear whether improving performance on this metric will ultimately improve outcomes in a clinically significant manner. The goal of this study was to expand the understanding of how clinical processes of care in asthma, as measured based on 3 different process measures, are related to clinical outcomes in a large sample of the Medicaid population spanning both pediatric and adult age groups. METHODS To compare the association between quality metrics and asthma exacerbations among Medicaid beneficiaries, we defined a cohort of subjects with persistent asthma in 2001 and 2002, measured the quality of care each beneficiary received in 2002, and then tested whether patients who received 961

2 962 YONG AND WERNER J ALLERGY CLIN IMMUNOL NOVEMBER 2009 Abbreviations used ED: Emergency department HEDIS: Healthcare Effectiveness Data and Information Set NCQA: National Committee for Quality Assurance OR: Odds ratio care measured as high quality were less likely to have subsequent asthma exacerbations in 2003 (Fig 1). Data We used the Medicaid Analytic Extract files from California and New York from Data include beneficiary-level demographic, enrollment, and utilization data for all outpatient, inpatient, and pharmacy claims covered by Medicaid. Study population As defined by HEDIS, beneficiaries aged 5 to 56 years were classified with persistent asthma if they met at least 1 of the following 4 criteria in both 2001 and 2002 (Table I) 17 : (1) at least 1 ED visit with asthma (International Classification of Diseases, ninth revision, code 493.xx) as a principal diagnosis; (2) at least 1 inpatient hospitalization with asthma as a principal diagnosis; (3) at least 4 outpatient visits with the diagnosis of asthma and at least 2 asthma medication dispensing events (includes inhaled corticosteroids, leukotriene antagonists, oral mast cell stabilizers, methylxanthines, and long-acting and short-acting b-agonists); or (4) at least 4 asthma medication dispensing events. Only those beneficiaries continuously enrolled in Medicaid for the entire 36-month study period from were included in the study to ensure complete medical claims. Outcome variable To determine the effect of measured quality on the likelihood of having an asthma exacerbation, we defined exacerbations as both a dichotomous variable indicating any ED visit or hospitalization with asthma as a principal diagnosis or oral steroid prescription in 2003 and as the number of ED visits and hospitalizations with asthma as a principal diagnosis and oral steroid prescriptions in Quality metrics We assessed asthma quality for all beneficiaries in our study cohort in 2002 using 3 quality metrics (Table I). First, we used the current HEDIS Use of Appropriate Medications for People with Asthma measure. This metric assesses whether asthmatic subjects have at least 1 controller medication prescription in a calendar year. Second, we measured whether asthmatic subjects had at least 4 controller medication prescriptions in a calendar year. This is a higher standard of quality than the usual HEDIS measure and therefore might be more highly indicative of high-quality care. We chose a cut point of 4 to make our analyses comparable with prior published literature using this cut point. 14,15 However, after testing multiple cut points, our results were not sensitive to this choice. Third, we measured whether each beneficiary had a controller-to-total asthma medication ratio of at least 0.5. This ratio expresses the percentage of total asthma medication prescription fillings, which includes controller and short-term reliever medications, dispensed as controller medications. This metric might better reflect control of asthma symptoms because those with well-controlled disease will need less short-term reliever medication and thus will have a higher ratio. In all cases we recorded beneficiary-level compliance with each asthma quality metric dichotomously. Asthma medications were classified as controller and noncontroller medications by using published lists from the NCQA. 18 FIG 1. Study design. Control variables We controlled for demographic data, including sex, age, race, and state of residence. We also calculated the Charlson comorbidity index for each beneficiary and categorized the sample into 3 groups based on comorbidity burden (score of 0, 1-3, or 4). This index predicts the 1-year mortality for patients based on a range of 20 comorbid conditions by using International Classification of Diseases, ninth revision, codes. Each comorbid condition has a numeric score depending on the mortality risk associated with the condition, and individual scores are summed to yield a total score that predicts mortality, with higher scores indicating higher mortality risk. 19 We included the Charlson comorbidity index in our analyses to account for the effect of competing medical demands on patients disease self-management because both the severity and number of comorbidities might negatively affect self-management abilities. 20,21 To account for asthma-specific illness severity, we included prior acute clinical service use for asthma (ED visits and hospitalizations with a principal diagnosis of asthma) and office visits with a diagnosis of asthma as control variables. Prior acute service use was assessed in 2001 as the number of ED visits and hospitalizations while prior number of office visits were also assessed in the same year. Although some prior studies have used claims-based asthma severity indices based on a mixture of pharmacy, ED, and hospital claims, we elected to use this measure of prior service use for 2 reasons. First, it indirectly accounts for disease severity. Second, it more directly accounts for personal preferences to use ED visits for evaluation of asthma exacerbations rather than outpatient visits, which might confound the relationship between process and outcomes. Analyses We calculated the unadjusted odds of having an asthma exacerbation (with respective 95% CIs) for each of the 3 quality metrics using logistic regression. We then ran nested logistic regressions to determine the effects of 2 groups of covariates on the odds of having an asthma exacerbation. First, we adjusted for demographic characteristics, including sex, age, race, and state of residence. Second, we added the Charlson comorbidity index and frequency of prior ED visits, hospitalizations, and office visits for asthma as covariates. We also tested the relationship between the number of ED visits, hospitalizations, and oral steroid prescriptions and each quality metric using negative binomial regression. We also repeated the analyses, stratifying the population into age groups (5-19, 20-40, and 41 years). Because claims data from beneficiaries enrolled in Medicaid managed care might be incomplete, we repeated all analyses by excluding managed care enrollees to test the robustness of our results. This study was approved by the University of Pennsylvania Institutional Review Board. RESULTS Cohort characteristic More than 90,000 Medicaid beneficiaries, of whom 57,032 (62.7%) were female, met the criteria for persistent asthma (Table II). The mean age of the cohort was 33.9 years (SD, 17.2

3 J ALLERGY CLIN IMMUNOL VOLUME 124, NUMBER 5 YONG AND WERNER 963 TABLE I. Description of eligibility criteria and quality metrics for asthma Eligibility Beneficiaries who met at least 1 of the following criteria in both 2001 and 2002 were defined as having persistent asthma: At least 1 ED visit with asthma as a principal diagnosis At least 1 inpatient discharge with asthma as a principal diagnosis At least 4 outpatient visits with asthma as one of the listed diagnoses and at least 2 asthma medication dispensing events At least 4 asthma medication dispensing events Quality metrics Assessed each beneficiary for each of the following quality metrics in 2002: Filling of at least 1 asthma controller medication prescription Filling of at least 4 asthma controller medication prescriptions Controller-to-total asthma medication ratio 0.5 years). Approximately one third of the beneficiaries were white (33.6%), and almost one quarter were either black (22.0%) or Hispanic (23.0%). Forty-eight percent resided in California, and 52% resided in New York. Approximately 14.0% of included patients had a Charlson index of 0 points. Seventy-six percent of the cohort had a Charlson index of between 1 and 3 points, and 10.0% had indices of at least 4 points. Eighteen percent had an ED visit for asthma in either 2001 or 2002, and 8,595 (9.5%) had a hospitalization for asthma in either 2001 or Almost 15,000 (16.1%) had 4 outpatient visits for asthma along with at least 2 asthma medication dispensing events in either 2001 or 2002, whereas more than 99.0% of the beneficiaries had at least 4 asthma medication dispensing events in the same time period. Approximately 83.9% of subjects with persistent asthma had at least 1 controller medication dispensing in 2002, whereas 60.3% had at least 4 controller medication dispensing events that year. Forty-seven percent of the cohort had a controller-to-total asthma medication ratio of 0.5 or greater. Thirty-nine percent of included beneficiaries had an ED visit, hospitalization, and/or oral steroid prescription for asthma in Association with acute service use for asthma In unadjusted analyses subjects with persistent asthma who met the HEDIS quality metric of having at least 1 controller medication dispensing event were twice as likely to experience asthma exacerbations in 2003 compared with those who had no asthma controller medication dispensing events (Table III). When considering the multiple controller metric, those who met this quality metric were 51.0% more likely to have exacerbations than those who obtained less than 4 controller-dispensing events. In comparison, patients with controller-to-total asthma medication ratios of at least 0.5 were 27.0% less likely to have exacerbations compared with those with ratios of less than 0.5. After including demographic characteristics and subsequently the Charlson index and prior acute care and outpatient service use as covariates, no significant qualitative changes were noted in the odds of an exacerbation across the 3 quality metrics (Table IV). Those who had at least 1 controller medication dispensing event remained significantly more likely to experience asthma exacerbations compared with those without any such event in the adjusted models (odds ratios [ORs], 1.96 [95% CI, ] and 1.80 [95% CI, ], respectively). Subjects with persistent asthma with at least 4 controller medication dispensing events also had exacerbations more frequently than those with less than 4 dispensings in both models (ORs, 1.53 [95% CI, ] and 1.44 [95% CI, ], respectively). In contrast, those beneficiaries with controller-to-total asthma medication ratios of at least 0.5 remained approximately 23.0% less likely to have exacerbations compared with those with ratios of less than 0.5 in both models (ORs, 0.75 [95% CI, ] and 0.77 [95% CI, ], respectively). When the analyses were stratified by age group, there was no qualitative change in the results, with a higher likelihood of exacerbations among those with controller medication dispensing events and lower likelihood among those with a controller-to-total asthma medication ratio of at least 0.5 (Table V). The likelihood of asthma exacerbations significantly increased with age in both absolute count-based metrics. However, the only statistically significant difference when considering the ratio measure was seen between the older age groups. No significant qualitative changes were noted regardless of whether the primary outcome variable was analyzed as a dichotomous variable or as the number of ED visits, hospitalizations, and oral steroid dispensing events for asthma. Excluding beneficiaries enrolled in Medicaid managed care programs also had no significant effect on the results. DISCUSSION This study compared the association of 3 asthma processof-care quality measures with clinical asthma outcomes. Our analyses found that in a population including both pediatric and adult subjects with persistent asthma, the filling of either at least 1 or 4 asthma controller medication prescriptions by Medicaid beneficiaries was associated with a higher likelihood of future ED visits, hospital admissions, and oral steroid dispensing events for asthma. In contrast, those beneficiaries with a controller-to-total asthma medication ratio of at least 0.5 were approximately 23.0% less likely to have future exacerbations. The filling of at least 1 controller medication prescription is the current HEDIS asthma quality measure and has been increasingly incorporated into health insurance plan quality assessments and pay-for-performance reimbursement models. 4 This measure was developed based on national asthma care guidelines and evidence from rigorous clinical trials that have demonstrated that subjects with persistent asthma who receive controller medication require fewer ED visits and hospitalizations for asthma. 4 Appropriate use of controller medications by subjects with persistent asthma is a part of delivering high-quality care to patients with asthma. However, claims-based studies examining the relationship between controller medication dispensing events and clinical outcomes have found divergent results. Some concluded that those asthmatic subjects who receive at least 1 controller medication require less frequent ED use and hospitalizations, 7-10 whereas others found the opposite Studies focusing on those with at least 4 controller medication dispensing event have been

4 964 YONG AND WERNER J ALLERGY CLIN IMMUNOL NOVEMBER 2009 TABLE II. Cohort demographics (n590,909) Characteristics Sex Female, no. (%) 57,032 (62.7) Age (y), mean (SD) 33.9 (17.2) Race, no. (%) White 30,551 (33.6) Black 19,954 (22.0) Hispanic 20,931 (23.0) Asian/Pacific Islander 2,195 (2.4) Other 17,258 (19.0) State of residence, no. (%) California 43,761 (48.1) New York 47,158 (51.9) Charlson comorbidity index, no. (%) 0 12,645 (13.9) ,207 (76.1) 4 9,057 (10.0) Criteria for persistent asthma in 2001 or 2002 At least 1 ED visit* 16,522 (18.2) At least 1 hospitalization* 8,595 (9.5) At least 4 outpatient visits and at least 2 14,666 (16.1) asthma medication dispensing eventsà At least 4 asthma medication dispensing 90,200 (99.2) eventsà Asthma quality metric in 2002, no. (%) Filling of at least 1 controller medication 76,250 (83.9) dispensing Filling of at least 4 controller medication 54,821 (60.3) dispensing events Controller-to-total asthma medication ratio 42,905 (47.2) 0.5 Any asthma exacerbation in 2003, no. (%) 35,390 (38.9) *With principal diagnosis of asthma. With a diagnosis of asthma. àasthma medications include both reliever and controller medications. Includes ED use, hospitalization, and/or oral steroid use for asthma. similarly divergent, with some finding a protective affect against asthma mortality 14 and ED use, 15 and another finding an association with increased acute care use. 13 The limited studies on the controller-to-total asthma medication ratio have been more consistent, finding that those with a higher ratio had lower use of acute care services for asthma. 10,13 One of the reasons for these conflicting results might be that studies have used different criteria to identify asthmatic subjects, ranging from a single hospitalization or ED visit for asthma to use of asthma medications to the original HEDIS criteria for persistent asthma (including outpatient, inpatient, and pharmacy use specific to asthma). These differences could alter the sample included in the studies, thus potentially biasing the analyses. Studies have also varied in the clinical outcomes examined, with some focusing on hospitalizations only and others including oral steroid use and ED visits among their clinical outcomes. Finally, and potentially most troubling, these contradictory results might reflect confounding from unobserved clinical severity because asthmatic subjects with more severe disease are more likely to both use controller medications and acute care. 25 Our study, which includes data from a large number of Medicaid beneficiaries both children and adults spanning 3 years, is the first to our knowledge to use the most recently TABLE III. Unadjusted ORs of asthma exacerbations by qualityof-care metric Quality metric OR (95% CI) Filling of at least 1 controller medication dispensing 1.99 ( ) in 2002 Filling of at least 4 controller medications dispensings 1.51 ( ) in 2002 Controller-to-total asthma medication ratio ( ) revised HEDIS criteria for persistent asthma to examine the relationship between the process of filling controller medication prescriptions for asthma and exacerbations. By extending the identification method for persistent asthma to require meeting criteria in both of 2 consecutive years instead of just 1 year, the likelihood of accurately identifying subjects with persistent asthma increases. This method is more likely to identify the population most likely to benefit from controller medication use. Despite this, we find worse outcomes among subjects with persistent asthma with a dispensing of controller medications. This finding that Medicaid beneficiaries who fill either at least 1 or 4 controller medication prescriptions are more likely to experience asthma exacerbations is consistent with bias related to unmeasured disease severity. We attempted to control for disease severity using both the Charlson comorbidity index and a measure of prior service use. Indeed, including these disease severity measures decreased the effect of each process measure on outcomes. However, our ability to control for disease severity is limited by the level of clinical detail available in administrative claims data. Our finding of worse clinical outcomes among patients receiving controller medications is undoubtedly related, at least in part, to unmeasured disease severity and is consistent with accumulating evidence suggesting that more severely ill patients have a higher likelihood of meeting the evidence-based guidelines reflected in process measures This hypothesis is additionally supported by evidence of a differential effect of age because the likelihood of comorbidities increases with age, and our results show a higher likelihood of exacerbations among older beneficiaries who receive controller medications compared with younger patients. The finding that those patients with better performance on the controller-to-total asthma medication ratio were less likely to have exacerbations might indicate that the ratio metric more accurately reflects control of asthma and is less sensitive to unmeasured disease severity. The similar likelihood of exacerbations among those with better performance on the ratio measure, regardless of age, also supports this theory. Whereas subjects with persistent asthma who use controller medications might still have poorly controlled asthma requiring rescue therapy and high levels of exacerbations, subjects with persistent asthma who use more controller medications relative to short-term reliever medications (which are included with counts of controller medications to obtain the denominator of the ratio) might have better control of their asthma and thus require less acute service use. Our results are limited by the accuracy and completeness of the claims data submitted by Medicaid programs in California and New York. However, we tested the robustness of our results

5 J ALLERGY CLIN IMMUNOL VOLUME 124, NUMBER 5 YONG AND WERNER 965 TABLE IV. Adjusted ORs of asthma exacerbations by quality-of-care metric OR (95% CI) Covariates At least 1controller At least 4 controllers Controller-to-total ratio $0.5 Adjusted for sex, age, race, state of residence 1.96 ( ) 1.53 ( ) 0.75 ( ) Adjusted for sex, age, race, state of residence, Charlson 1.80 ( ) 1.44 ( ) 0.77 ( ) comorbidity index, prior office visits, and acute service use TABLE V. Adjusted* ORs of asthma exacerbations by quality-of-care metric stratified by age and comparison of ORs between age groups Quality metric $1 Controller medication $4 Controller medications Controller-to-total ratio $0.5 Age group 5-19 y 1.38 ( ) 1.24 ( ) 0.76 ( ) y 1.78 ( ) 1.41 ( ) 0.73 ( ) 41 y 2.08 ( ) 1.62 ( ) 0.78 ( ) P value 5-19 y vs y < y vs 41 y <.01 < y vs 41 y <.01 < *Adjusted for sex, age, race, state of residence, Charlson comorbidity index, prior outpatient visits, and prior acute service use. by repeating our analyses excluding those beneficiaries enrolled in Medicaid managed care programs because the claims for these beneficiaries are often incomplete, and we saw no qualitative change in our results. Also, because asthma severity classifications are clinically based, we could not accurately account for the effect of asthma severity, the use of subspecialty care (eg, pulmonary or allergy consultation), or other potential confounding variables using only claims information. However, assuming that those with more severe disease are more likely to use acute care services, such as the ED and inpatient stays, we indirectly accounted for disease severity and accounted for personal preferences to use ED visits for evaluation of asthma exacerbations by including assessment of acute care service use in 2001 in our analyses. Also, because of the observational design of the study, we cannot infer causality between performance on the quality metrics and clinical outcomes. Finally, because our study was limited to those enrolled in California and New York, our results might not be generalizable to all Medicaid beneficiaries with persistent asthma. However, the Medicaid programs in California and New York together accounted for approximately 25.0% of the nation s Medicaid beneficiaries. 28 Appropriate treatment of persistent asthma with controller medications is an important component of high-quality care. By incorporating this process into quality measurement programs, such as HEDIS, appropriate use of these medications might increase. Increasing appropriate use of controller medications is an appropriate goal of any asthma-related quality improvement initiative. However, in the setting of tying performance measures to external incentives such as pay-for-performance, this process measure provides incomplete information about providers asthma-related quality of care if used alone. Other metrics, such as the controller-to-total asthma medication ratio, provide additional and important information about asthma control that might be less affected by disease severity. If the ultimate goal of measuring the quality of care delivered to asthmatic subjects is to improve their clinical care, then adequate assessment of asthma care quality should extend beyond process measures that are poorly associated with good clinical outcomes and likely needs to incorporate evaluation of both the absolute numbers of controller medications dispensed and the ratio of controller-to-total asthma medications. We thank Ying Huang for assistance with database management. Key messages d Although appropriate treatment of asthma with controller medications is an important component of high-quality care, quality metrics based on this process of care vary in their association with clinical outcomes. d Adequate assessment of quality of care for asthma should include process measures that are predictive of good clinical outcomes. REFERENCES 1. American Lung Association: Epidemiology and Statistics Unit Trends in asthma morbidity and mortality. Available at: c5dvluk9o0e&b Accessed March 22, Hennessy S, Carson JL, Ray WA, Strom BL. Medicaid databases. In: Strom BL, editor. Pharmacoepidemiology. West Sussex, England: John Wiley & Sons Ltd; p National Committee on Quality Assurance. Available at: Accessed April 13, Gelfand EW, Colice GL, Fromer L, Bunn WB 3rd, Davies TJ. Use of the HEDIS for measuring and improving the quality of asthma care. Ann Allergy Asthma Immunol 2006;97: Pauwels RA, Pedersen S, Busse WW, Tan WC, Chen YZ, Ohlsson SV, et al. Early intervention with budesonide in mild persistent asthma: a randomized, doubleblind trial. Lancet 2003;361: Barnes NC, Miller CJ. Effect of leukotriene receptor antagonist therapy on the risk of asthma exacerbations in patients with mild to moderate asthma: an integrated analysis of zafirlukast trials. Thorax 2000;55:

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Available at: Accessed March 22, Celebrating JACI s 80th Anniversary Arthur F. Coca, Editorial Board Member Arthur Coca ( ), born in Philadelphia, Pa, of Spanish noble heritage, attended Haverford College (AB, 1896) and the University of Pennsylvania (MA, 1899; MD, 1900). He trained in pathology, bacteriology, and immunology for 6 years at Pennsylvania, initially with Simon Flexner, who introduced him to experimental sensitization, and in chemistry at the German Heidelberg Cancer Institute ( ). Working with Emil von Dungerin generated his interest in blood groups, which motivated him to establish the first municipal-wide cooperative blood donor program in 1928 in New York, NY. After 2 years in Manila with the Philippine Bureau of Science during a cholera epidemic, he joined Cornell University Medical College, New York, as an instructor in pathology and bacteriology. Advancing in 1919 first to professor of immunology and subsequently to chief of the newly created Laboratory of Applied Immunology at New York Hospital, he developed procedures for extraction and standardization of allergens. Concurrently he contributed to teaching, graduate training, and research programs at Robert Cooke s pioneering allergy clinic, and with Cooke, he introduced the concept of atopy in allergic disease. As founder and first editor of the Journal of Immunology in 1916 for a 25-year tenure, Coca provided an initial US medium for publications on allergy.