Socioeconomic characteristics of patients undergoing ambulatory diagnostic cerebral angiography in four US States.

AIMS: Several groups have demonstrated the safety of ambulatory cerebral angiography, with no patients experiencing complications related to early discharge. Although this practice appears to be safe, the socioeconomic characteristics factoring in the selection of the patients have not been investigated.

METHODS: We performed a retrospective cohort study involving 45,226 patients undergoing outpatient and 159,046 undergoing inpatient cerebral angiography, who were registered in the State Ambulatory Surgery Databases (SASD) and State Inpatient Databases (SID) respectively for 4 US States (New York, California, Florida, North Carolina).

RESULTS: In a multivariate analysis of diagnostic cerebral angiography, Caucasian race (OR 1.36, 95% CI, 1.31, 1.42) and male gender (OR 1.36, 95% CI, 1.31, 1.41), were significantly associated with outpatient procedures. Higher Charlson Comorbidity Index (CCI) (OR 0.60, 95% CI, 0.54, 0.67), high income (OR 0.70, 95% CI, 0.67, 0.73), high volume hospitals (OR 0.69, 95% CI, 0.66, 0.73), and coverage by Medicare/Medicaid (OR 0.96, 95% CI, 0.92, 0.99) were associated with a decreased chance of outpatient procedures. Institutional charges were significantly less for outpatient cerebral angiography. The median charge for inpatient diagnostic cerebral angiography was $26,968 as compared to $16,151 in the outpatient setting (P < 0.0001, Student's t-test).

CONCLUSION: Access to ambulatory diagnostic cerebral angiography appears to be more common for patients with private insurance and less comorbidities, in the setting of lower volume hospitals. Further investigation is needed in the direction of mapping these disparities in resource utilization.