Possible Hypertension Medication Gaps in Veterans Switching Healthcare Systems
The failure of patients to adhere to a prescribed medication regime is a principal reason behind failed blood pressure control. One factor that has been largely overlooked in adherence research is transitions between plans or payers that provide drug coverage. This may be of particular concern because under the Medicare Modernization Act of 2003 (Medicare Part D) all Medicare beneficiaries have the option to switch plans on a yearly basis; individuals dually eligible for Medicaid and Medicare can switch plans on a monthly basis. This study sought to measure the relationship between switching healthcare systems (VA and Medicaid) when filling prescriptions and gaps in medication adherence for Veterans (n=61,352) with a diagnosis of hypertension. Using VA and Medicaid/Medicare data, investigators examined prescription drug claims for alpha-blockers, beta-blockers, angiotensin converting enzyme (ACE) inhibitors, calcium channel blockers, and diuretics during 1999 and 2000. Medication gaps were defined as the percent of days Veterans did not have medication.
Findings show a significant and positive relationship between switching healthcare systems where prescriptions are filled and medication gaps when all drug classes are combined. Veterans who switched between healthcare systems were predicted to significantly increase their percent of days without drugs by 7% compared to individuals who received their drugs in one system. When models for each drug class were predicted separately, the effect remained significant for calcium-channel blockers - and bordered on significant for ACE inhibitors. No evidence of a relationship between switching and medication gaps was seen for beta-blockers, alpha-blockers, or diuretics. The authors suggest that healthcare policymakers and providers pay particular attention to patients who are switching payers for drug coverage because their medication regime may be compromised.
Prentice J, Pizer S, and Houranieh A. Changing source of prescription fills and medication gaps. American Journal of Pharmacy Benefits 2011;3(2):e14-e23.
This study was funded by HSR&D (ECI 03-199). Drs. Prentice and Pizer are part of VA's Health Care Financing & Economics (HCFE) located in Boston, MA.