Impact of insurance carrier, prior authorization, and socioeconomic status on appropriate use of SPECT myocardial perfusion imaging in private community-based office practice.

backgroundThe impact of health insurance carrier and socioeconomic status (SES) on the adherence to appropriate use criteria (AUC) for radionuclide myocardial perfusion imaging (MPI) is unknown. HYPOTHESIS: Health insurance carrier's prior authorization and patient's SES impact adherence to AUC for MPI in a fee-for-service setting.

methodsWe conducted a prospective cohort study of 1511 consecutive patients who underwent outpatient MPI in a multi-site, office-based, fee-for-service setting. The patients were stratified according to the 2009 AUC into appropriate/uncertain appropriateness and inappropriate use groups. Insurance status was categorized as Medicare (does not require prior authorization) vs commercial (requires prior authorization). Socioeconomic status was determined by the median household income in the ZIP code of residence.

resultsThe proportion of patients with Medicare was 33% vs 67% with commercial insurance. The rate of inappropriate use was higher among patients with commercial insurance vs Medicare (55% vs 24%; P < 0.001); this difference was not significant after adjusting for confounders known to impact AUC determination (odds ratio: 1.06, 95% confidence interval: 0.62-1.82, P = 0.82). The mean annual household income in the residential areas of patients with inappropriate use as compared to those with appropriate/uncertain use was $72 000 ± 21 000 vs $68 000 ± 20 000, respectively (P < 0.001). After adjusting for covariates known to impact AUC determination, SES (top vs bottom quartile income area) was not independently predictive of inappropriate MPI use (odds ratio: 0.9, 95% confidence interval: 0.53-1.52, P = 0.69).

conclusionsInsurance carriers prior authorization and SES do not seem to play a significant role in determining physicians adherence to AUC for MPI.