REN and Hypertension: Because pharmacy claims could not be linked to medical claims in the Maine APCD, we limited our analysis to renin–angiotensin system antagonists (RASAs), which are used exclusively for hypertension (RASA medications include angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, and direct renin inhibitors and are used only for hypertension, unlike other antihypertensive medications).