title: Health Resource Utilization and Direct Costs Associated with Angina for Patients with Coronary Artery Disease in a US Managed Care Setting.
abstract: BACKGROUND
  Angina is often a first symptom of coronary artery disease (CAD); however, the specific burden of illness for patients with CAD-associated angina in managed care has not been reported.
  
  
  OBJECTIVE
  To determine the clinical and cost burden of illness for patients with CAD-associated angina in a managed care environment.
  
  
  METHODS
  A retrospective database analysis in a nationwide commercial managed care plan.
  
  
  METHODS
  This study included patients with International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic or procedure codes for CAD between July 1, 2004, and June 30, 2006, who had data available for the period 6 months before and 12 months after the index date. The primary analyses for patients classified as having CAD with angina were based on a 3-algorithm patient-identification model (combined positive predictive value of 89%, 95% confidence interval, 0.79-0.95). Utilization measures for the 12-month postindex period, annual CAD-related direct costs, and total all-cause costs (ie, medical plus pharmacy) were determined. A generalized linear model was used to compare CAD-related costs and overall costs.
  
  
  RESULTS
  Of the 246,227 patients with CAD, the 3-algorithm model assigned 230,919 patients (93.8%) to the CAD-without-angina cohort and 15,308 (6.2%) to the CAD-with-angina cohort. Patients with angina were more likely than patients without angina to be hospitalized (41% vs 11%, respectively; P <.001), to visit the emergency department (34% vs 12%, respectively; P <.001), to have office visits (94% vs 79%, respectively; P <.001), and to have more revascularization procedures (35% vs 8%, respectively; P <.001). Average CAD-related inpatient costs were $9536 versus $2169, and pharmacy costs were $1499 versus $891, for patients with and without angina, respectively. Total average CAD-related medical and pharmacy costs for patients with angina were $14,851 versus $4449 for patients with CAD without angina, and the average all-cause per-patient cost was $28,590 versus $14,334, respectively.
  
  
  CONCLUSIONS
  Based on these results, US patients with CAD plus angina in a managed care setting use significantly more healthcare services and incur higher costs than patients who have CAD without angina. Revascularization procedures are a major driver of these increased costs for those with CAD and angina.
authors.affiliation: Executive Director, Outcomes Research, CV Therapeutics (Gilead), Palo Alto, CA, at the time of the study and is currently an employee of Genzyme.
authors.forename: Judy
authors.initials: J
authors.lastname: Kempf
authors.affiliation: Associate Director, Observational Research, OptumInsight, Eden Prairie, MN.
authors.forename: Erin
authors.initials: E
authors.lastname: Buysman
authors.affiliation: Professor and Chair, Department of Pharmacotherapy, and Executive Director, Outcomes Research Center, University of Utah, Salt Lake City.
authors.forename: Diana
authors.initials: D
authors.lastname: Brixner