Impact of VA-Purchased Community Care on Polypharmacy and Potentially Inappropriate Medication Use in Older Adult...

To investigate whether eligibility for Veterans Health Administration (VA)-purchased community care, which expanded Veterans' access to care outside VA, was associated with increased polypharmacy or potentially inappropriate medication use among older adult Veterans.

Regression discontinuity design, leveraging the distance threshold for community care eligibility (residing > 40 miles from the nearest VA facility with ≥ 1 or more full-time primary care physician), to examine the effects of community care eligibility on polypharmacy and potentially inappropriate medication use among Veterans aged ≥ 65 years.

VA pharmacy data for all prescriptions filled at VA facilities, VA Program Integrity Tool files for prescriptions paid by VA and filled in community pharmacies, and Medicare Part D data. Analyses included annual cross-sectional samples of Veterans 36-39 miles or 41-44 miles from their nearest VA facility during FY 2016-2019.

The sample included 399,250 Veteran-year observations, of which 226,157 (56.6%) were 36-39 miles and 173,093 (43.4%) were 41-44 miles from the nearest eligible VA facility. Overall, we observed no discontinuities across the 40-mile threshold in the number of unique medications filled annually (-0.06 medications; 95% confidence interval [CI], -0.15 to 0.03). There were no discontinuities in proportions of Veterans filling ≥ 5 unique medications (-0.25 percentage points [pp]; 95% CI, -0.84 to 0.34), ≥ 10 medications (-0.55 pp.; 95% CI, -1.24 to 0.14), ≥ 1 medication on the Beers list (-0.02 pp.; 95% CI, -0.63 to 0.59), or ≥ 1 high-risk drug-drug interaction (-0.05 pp.; 95% CI, -0.17 to 0.07). Among Veterans with mental health conditions, exceeding the 40-mile threshold was associated with a higher likelihood of filling ≥ 10 unique medications annually (2.06 pp.; 95% CI, 0.42 to 3.70). We did not observe clinically or statistically significant discontinuities in other subgroups.

Overall, eligibility for VA-purchased community care was not associated with increased polypharmacy or potentially inappropriate medication use among older adult Veterans.