3053 — Impact of the Suppression of Substance Abuse Claims in Medicare and Medicaid Data: Implications for Research on Population Health in Veterans
de Groot KA, VIReC; Joyce MM, VIReC; Hynes DM, VIReC;
Many Veterans enrolled in Veterans Health Administration (VHA) also rely on Centers for Medicare and Medicaid (CMS) Services to meet their healthcare needs. VA researchers often use CMS data to capture a more complete picture of healthcare utilization. In 2014, CMS implemented policy restricting the disclosure of substance abuse (SA) records. CMS now suppresses an entire claim if it includes any procedure, diagnosis, or diagnosis related group (DRG) code related to SA. We studied how the suppression of SA claims might affect VA research.
We obtained the list of codes CMS used to suppress SA claims. We searched for these codes in 2009 Medicaid and 2011 Medicare claims data for Veterans (received prior to suppression of SA claims) to approximate the number of suppressed claims in future years of data. We also examined inpatient claims that contained these codes to determine how many were directly related to treatment of SA.
In Medicaid data, 9.87% of inpatient and 0.98% of non-inpatient claims contained a code for SA. In Medicare data, 3.51% of inpatient and 0.11% of non-inpatient claims contained a SA code. Review of inpatient claims show that most records (over 70%) that would be suppressed are due only to a diagnosis of SA, not a procedure related to SA. The majority of inpatient claims with SA codes had DRGs not directly related to SA. The most common DRGs were for cirrhosis and malignancy of hepatobiliary system in Medicaid, and for psychosis in Medicare.
Inpatient claims are more affected by the suppression of SA claims than other types of claims. The majority of claims that will be suppressed are not directly related to SA treatment.
Longitudinal analyses, especially those studying comorbidities and hospitalizations, will be impacted not only for patients diagnosed with SA, but also for other commonly associated diagnoses. The impact of SA claim suppression on VA research may be broad and result in biased and less reliable results. Efforts to enable use of all claims are critical for health policy research in all populations served by Medicare and Medicaid.