PMA8: DEVELOPMENT OF A CHRONIC DISEASE INDICATOR USING A MANAGED CARE POPULATION

Abstract

OBJECTIVES: Accurate determination of disease prevalence in large patient populations is difficult. The objective of this research was to use pharmacy data to develop an index that estimates the presence and number of chronic diseases in a managed care population. METHODS: An expert panel evaluated 246 specific medication classes as to their likelihood to be indicative of a chronic disease. Those classes identified were then compared against medical records from two random samples of persons 18 years of age or older continuously enrolled for at least one year in a health maintenance organization. One sample was drawn from all eligible persons (n = 137), while the other sample was restricted to individuals 50 years of age or greater (n = 138). A cumulative number of chronic conditions was designated the chronic disease index (CDI). Sensitivity and specificity were calculated for those conditions with prevalence greater than 10% based upon medical record review. RESULTS: The expert panel designated 54 drug classes as containing medications used to treat chronic conditions. A total of 5640 medications were dispensed over a 1 year period for the 275 subjects. The average total number of chronic conditions via medical record review was 2.89 + 2.07, compared to 1.33 + 1.21 chronic conditions estimated by medication use. The CDI correlated well with the number of chronic conditions found via record review (r = 0.735, p < 0.0001). The specificity of pharmacy records to indicate the presence of hypertension, dyslipidemia, depression, and diabetes was 79.9%, 99.0%, 90.2%, and 99.6%, respectively. The sensitivity was 90.9%, 49.9%, 77.5%, and 62.2% for hypertension, dyslipidemia, depression, and diabetes, respectively. CONCLUSIONS: The CDI correlates well with documented chronic conditions. Pharmacy data can be useful in identifying persons with diagnoses of hypertension, dyslipidemia, depression, and diabetes.