BACKGROUND:

Although once protected from cardiovascular disease (CVD), American Indians now have incidence rates higher than the general US population.

The majority of CVD cases occur in individuals with diabetes. It is therefore imperative that intervention strategies to reduce CVD in diabetic individuals be developed and validated in this population.

DESIGN NARRATIVE:

The randomized three year trial examines the effects on cardiovascular disease (CVD) of intensive LDL reduction (goal less than or equal to75 mg/dL) and intensive blood pressure lowering (goal less than or equal to 115/75 mmHg), compared to usual targets of less than or equal to 100 mg/dL and less than or equal to 130/85 mmHg. These cutpoints were chosen because mean LDL and blood pressure levels are lower in this population, but there is a strong relation between LDL, blood pressure, and CVD at levels below current targets. The primary endpoint will be carotid intimal-medial thickness.

Secondary endpoints will include cardiac function measures by echocardiography, lipoproteins, albuminuria, and C-reactive protein (CRP). The study will enroll 488 diabetic American Indian men and women more than 40 years of age and will be conducted in four field centers involving Indian Health/Tribal primary care facilities in Phoenix/Sacaton, Arizona; Chinle, Arizona; Rapid City/Pine Ridge, South Dakota; and Lawton, Oklahoma, with input from American Indian physicians and community members. Study results will provide evidence needed to develop community-based programs to treat and prevent the epidemic of CVD among American Indians. The data will also be valuable in understanding the effects of intensive risk-factor reduction on atherosclerosis burden and cardiac function in diabetic individuals in all US populations and provide evidence for determining LDL and blood pressure treatment goals for diabetic patients.