The Underutilization of Cardiac Medications of Proven Benefit, 1990 to 2002

Objectives: To evaluate recent trends, we examined longitudinal national data on the outpatient use of warfarin in atrial fibrillation (AF), beta-blockers and aspirin in coronary artery disease (CAD), and angiotensin-converting enzyme inhibitors (ACEIs) in congestive heart failure (CHF).

Background: Previous studies indicate that specific cardiac medications are underutilized.

Methods: We used the National Disease and Therapeutic Index (NDTI) (produced by IMS HEALTH, Plymouth Meeting, Pennsylvania) for 1990 to 2002, and the National Ambulatory Medical Care Surveys (NAMCS) for 1990 to 2000 to follow nationally representative samples of outpatient visits. For visits by patients with AF (total n = 14,634 visits), CAD (n = 35,295), and CHF (n = 33,008), we examined trends in the proportion of visits with the selected medications reported.

Results: Warfarin use in AF increased from 12% in 1990, to 41% in 1995, to 58% in 2001 in NDTI; a similar moderation of recent increase was seen in NAMCS. For CAD in NDTI, beta-blocker use increased slowly from 19% in 1990, to 20% in 1995, then to 40% in 2001; NAMCS showed this same pattern. Aspirin use in CAD in NDTI increased from 18% in 1990, to 19% in 1995, to 38% in 2001; NAMCS, however, showed lower use rates. For NDTI, ACEI use in CHF increased from 24% in 1990 to 36% in 1996, but increased to only 39% by 2001, a general pattern also seen in NAMCS.

Conclusions: Both national datasets demonstrate continuing underutilization of these cardiac medications of proven benefit. Although use is increasing, it remains lower than expected, and some increases noted in earlier years have slowed. Substantial public health benefits would result from further adoption of these effective therapies.