Rising tide of cardiovascular disease in American Indians - The Strong Heart Study

Background-Although cardiovascular disease (CVD) used to be rare among Amer ican Indians, Indian Health Service data suggest that CVD mortality fates v ary greatly among American Indian communities and appear to be increasing. The Strong Heart Study was initiated to investigate CVD and its risk factor s in American Indians in 13 communities in Arizona, Oklahoma, and South/Nor th Dakota. Methods and Results-A total of 4549 participants (1846 men and 2703 women 4 5 to 74 years old) who were seen at the baseline (1989 to 1991) examination were subjected to surveillance (average 4.2 years, 1991 to 1995), and 88% of those remaining alive underwent a second examination (1993 to 1995). The medical records of all participants were exhaustively reviewed to ascertai n nonfatal cardiovascular events that occurred since the baseline examinati on or to definitively determine cause of death. CVD morbidity and mortality rates were higher in men than in women and were similar in the 3 geographi c areas. Coronary heart disease (CHD) incidence rates among;American Indian men and women were almost 2-fold higher than those in the Atherosclerosis Risk in Communities Study. Significant independent predictors of CVD in wom en were diabetes, age, obesity (inverse), LDL cholesterol, albuminuria, tri glycerides, and hypertension. In men, diabetes, age, LDL cholesterol, album inuria, and hypertension were independent predictors of CVD. Conclusions-At present, CHD rates in American Indians exceed rates in other US populations and may more often be fatal. Unlike other ethnic groups, Am erican Indians appear to have an increasing incidence of CHD; possibly rela ted to the high prevalence of diabetes. In the general US population, the r ising prevalence of obesity and diabetes may reverse the decline in CVD dea th rates. Therefore, aggressive programs to control diabetes and its risk f actors are needed.