ATLANTA — The prevalence of cardiovascular risk factors and cardiovascular disease is alarmingly high and continues to rise in Native Americans, according to several reports at a prevention conference on heart disease and stroke sponsored by the Centers for Disease Control and Prevention.
In one study of adult Native Americans (defined as American Indians and Alaska Natives) from Montana who took part in an annual telephone survey, significant increases were seen between 1999 and 2003 in the proportion reporting diabetes (12% vs. 16%), hypertension (26% vs. 34%), high cholesterol (23% vs. 30%), and obesity (34% vs. 39%).
About 1,000 adults completed the survey in each of the four study years, Carrie S. Oser reported in a poster presented at the meeting.
After adjustment for age, sex, and survey year, the increases in the proportion reporting hypertension, high cholesterol, and obesity remained significant, said Ms. Oser of the Montana Department of Public Health and Human Services in Helena.
The prevalence of cardiovascular disease increased slightly from 10% to 11% over the course of the study, and smoking rates dropped slightly from 38% to 36%, although they remained high.
In another study of Native Americans in North Carolina, which has the eighth-largest Native American population in the United States, age-adjusted rates of cardiovascular risk factor prevalence were compared with those of North Carolina whites and African Americans.
The 285 Native Americans studied in 2002 and the 230 studied in 2003 had higher rates of hypertension (40% vs. 27%), obesity (33% vs. 21%), and diabetes (14% vs. 7%) than did whites.
They also were less likely than whites to engage in leisure-time physical activity (66% vs. 76%) and to engage in the recommended amount of physical activity for cardiovascular health (29% vs. 40%), and they were less likely to eat five or more servings of fruits and vegetables daily (19% vs. 25%), Sara L. Huston, Ph.D., reported in a poster.
Smoking and high cholesterol rates in this study were found to be comparable in American Indians and whites. All cardiovascular risk factors were found to be similar in Native Americans and African Americans, she said.
Both Ms. Oser and Dr. Huston said that they were struck by the high prevalence of cardiovascular risk factors found in Native Americans; the prevalence in this population had been largely unknown, noted Dr. Huston, who concluded that culturally appropriate intervention and prevention programs are needed to address the problem.
The need for such programs also was highlighted in another poster showing that with the rise in the prevalence of diabetes and hypertension in Native Americans is a likely risk in the prevalence of ischemic heart disease.
Based on 2002 ambulatory care data from the Indian Health Service, the age-adjusted prevalence of ischemic heart disease among Native Americans and Native Alaskans aged 45 years and older was estimated to be nearly three times higher in those with diabetes than in those without diabetes (17% vs. 6%).
Those individuals with hypertension but without diabetes had a higher age-adjusted prevalence of ischemic heart disease than did those with diabetes alone (13% vs. 7%). Those individuals with both diabetes and hypertension were found to have the highest prevalence (20%), reported Nilka Rios Burrows of the CDC, Atlanta.
These rates are likely to rise in tandem with the increasing prevalence of diabetes and other cardiovascular risk factors in Native Americans; interventions to control blood glucose, lipid, and blood pressure levels would benefit this population, she said.