Antihypertensive medication use in the Department of Veterans Affairs: a national analysis of prescribing patterns from 2000 to 2002.

BACKGROUND

Studies describe differences between recommendations for hypertension treatment and actual drug use. Antihypertensive use data from the Department of Veterans Affairs (VA) for 1995 to 1999 showed a downward trend for calcium antagonist (CA) use and increased use of beta-blockers (BB) and thiazide diuretics (TD). This study evaluates national VA antihypertensive treatment for 2000 to 2002 and compares these data to treatment data for 1995 to 1999.

METHODS

National VA pharmacy data were used to determine use of BB, TD, CA, angiotensin converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), and combinations of antihypertensive drugs for 2000 to 2002. Dispensing data were converted to treatment days. In addition to national trends, data were analyzed regionally to examine geographic differences. Pharmacoeconomic analysis estimated the financial impact of medication changes.

RESULTS

Antihypertensive drug use in the VA represented more than 1 billion days in 2002. The ACEI were most commonly used, representing 33.4% and 33.5% of treatment days in 2000 and 2002, respectively. Changes from 2000 to 2002 were 21.9% to 24.2% for BB, 29.3% to 24.4% for CA, and 13.2% to 14.2% for TD. Use of ARB increased from 2.1% to 3.7% of treatment days. Analysis of the 21 VA regions showed geographic variation. For example, the proportion of BB treatment days is highest in a northeast VA region (28.6%) and lowest in a southeast region (19.9%). In 2002 the VA has saved an estimated US 8.5 million dollars because of changes in medication use.

CONCLUSIONS

As a proportion of antihypertensive agent use, CA continues to fall in the VA, whereas BB, TD, and ARB use have increased. However, TD use remains low, despite national guidelines that promote use of this class of agent.