Characterization of Bariatric Surgery and Outcomes using Administrative Claims Data in the Research Network of a Nationwide Commercial Health Plan (Preprint)

Abstract

Administrative claims data could facilitate longitudinal ascertainment of health outcomes across multiple health systems during defined enrollment periods within health plans. As a result, the supplementation of electronic health records data with administrative claims data may be used to capture outcome events more comprehensively in longitudinal comparative effectiveness observational studies.

To investigate the utility of administrative claims data to identify and capture outcomes across health systems using a comparative effectiveness study of different types of bariatric surgery as a model.

This observational cohort study identified Anthem members who had bariatric surgery between 01/01/2007 and 12/31/2015 within the HealthCore Anthem Research Network (HCARN) database in the National Patient-Centered Clinical Research Network (PCORnet) common data model. Using HCARN bariatric claims, we identified patients whose procedures were performed in a member facility of one of the health systems affiliated with PCORnet Clinical Research Networks (CRNs). The main short-term adverse event outcome of interest was a composite of venous thromboembolism, reintervention, failure of discharge from the hospital, and death within 30 days after bariatric surgery. The long-term outcomes included all-cause hospitalization, abdominal operation or intervention, and in-hospital death up to 5 years after the procedure. Events were classified as occurring within or outside PCORnet CRN health systems by linking facility identifiers and events from all available CRNs and claims data.

We identified 4,899 patients who had bariatric surgery in one of the PCORnet CRN health systems. For 30-day composite adverse events, the inclusion of HCARN multi-site claims data marginally increased the incidence rate based only on HCARN single-site claims data for PCORnet CRN health systems from 3.9% to 4.2%. During the 5-year follow-up period, 56.8% of all-cause hospitalizations, 31.2% major abdominal operations or interventions, and 32.3% of in-hospital deaths occurred outside PCORnet CRN health systems. Incidence rates for long-term outcomes (events per 100 patient-years) were significantly lower when based on claims from a single PCORnet CRN health system only compared to using claims from all health systems in the HCARN across all outcomes: all-cause hospitalization, 12.5 (95% Confidence Interval [CI]: 11.9, 13.2) to 25.3 (95% CI: 24.4, 26.3); abdominal operation or intervention, 4.4 (95% CI: 4.0, 4.8) to 6.1 (95% CI: 5.7, 6.6); in-hospital death, 0.2 (95% CI: 0.12, 0.29) to 0.3 (95% CI: 0.19, 0.38).

Short-term inclusion of multi-site claims data only marginally increased the incidence rate computed from single-site claims data alone. Longer term follow up captured a notable number of events outside of PCORnet CRN health systems. The incidence rates for long-term outcomes were significantly lower when derived from claims from a single PCORnet CRN health system compared all claims.

Not applicable