Frequency of Care and Mortality Following an Incident Diagnosis of Peripheral Artery Disease in the Inpatient or Outpatient Setting: The ARIC (Atherosclerosis Risk in Communities) Study

Background-Available health services data for individuals with peripheral artery disease (PAD) are often from studies of those eligible for or undergoing intervention. Knowledge of the frequency of care and mortality following an initial PAD diagnosis by setting (outpatient versus inpatient) is limited and represents an opportunity to provide new benchmark information. Methods and Results-The purpose of this study was to characterize the frequency of care and mortality following an incident PAD diagnosis in the outpatient or inpatient setting using data from the ARIC (Atherosclerosis Risk in Communities) study cohort linked with Centers for Medicare and Medicaid Services fee-for-service claims data (2002-2012). Direct standardization was used to estimate age-standardized rates of encounters and mortality. PAD was defined by billing code in any claim position. We observed 1086 incident PAD cases (873 outpatient, 213 inpatient). At 1 year after diagnosis, participants diagnosed in the outpatient setting had 2.15 (95% confidence interval [CI], 2.10-2.21) PAD-related outpatient encounters per person-year, and 6.4% (95% CI, 4.8-8.1) had a PAD-related hospitalization. Conversely, participants diagnosed in the inpatient setting had 1.02 (95% CI, 0.94-1.10) PAD-related outpatient encounters per person-year, and 14.2% (95% CI, 9.3-18.7) had a PAD-related rehospitalization. One-year mortality was 7.1% (95% CI, 5.4-8.7) and 16.0% (95% CI, 11.0-21.1) among those diagnosed in outpatient and inpatient settings, respectively. Conclusions-This study provides important data estimating frequency of care and mortality by the setting of initial PAD diagnosis. Individuals with PAD are frequent users of health care, and those diagnosed in the inpatient setting have high rates of rehospitalization and mortality.