Volume 53 | Number S3 | December 2018

Abstract List

Carolyn T. Thorpe Ph.D., M.P.H., Walid F. Gellad, Maria K. Mor Ph.D., John P. Cashy Ph.D., John R. Pleis Ph.D., Courtney H. Van Houtven Ph.D., Loren J. Schleiden M.S., Joseph T. Hanlon Pharm.D., M.S., Joshua D. Niznik Pharm.D., Ronald L. Carico Pharm.D., M.P.H., Chester B. Good M.D., M.P.H., Joshua M. Thorpe Ph.D., M.P.H.


To evaluate the effect of dual use of /Medicare Part D drug benefits on antihypertensive medication supply in older Veterans with dementia.

Data Sources/Study Setting

National, linked 2007–2010 Veterans Affairs () and Medicare utilization and prescription records for 50,763 dementia patients with hypertension.

Study Design

We used inverse probability of treatment ()‐weighted multinomial logistic regression to examine the association of dual prescription use with undersupply and oversupply of antihypertensives.

Data Collection/Extraction Methods

Veterans Affairs and Part D prescription records were used to classify patients as ‐only, Part D‐only, or dual /Part D users of antihypertensives and summarize their antihypertensive medication supply in 2010: (1) appropriate supply of all prescribed antihypertensive classes, (2) undersupply of ≥1 class with no oversupply of another class, (3) oversupply of ≥1 class with no undersupply, or (4) both undersupply and oversupply.

Principal Findings

Dual prescription users were more likely than ‐only users to have undersupply only ( = 1.28; 95 percent  = 1.18–1.39), oversupply only ( = 2.38; 95 percent  = 2.15–2.64), and concurrent under‐ and oversupply ( = 2.89; 95 percent  = 2.53–3.29), versus appropriate supply of all classes.


Obtaining antihypertensives through both and Part D was associated with increased antihypertensive under‐ and oversupply. Efforts to understand how best to coordinate dual‐system prescription use are critically needed.