Chronic disease risk factors among Alaska Native and American Indian people, Alaska, 2004-2006

Abstract

Introduction: The Alaska Education and Research Towards Health (EARTH) Study is being conducted to determine the prevalence of clinically measured chronic disease risk factors in a large population of American Indian/Alaska Native people (AI/AN). We report these estimates and compare them with those for the overall US population, as assessed by the National Health and Nutrition Examination Survey (NHANES).

Methods: We measured blood pressure, height, weight, and fasting serum lipids and glucose in a prospective cohort of 3,822 AI/AN participants who resided in Alaska during 2004 through 2006. We categorized participants as having chronic disease risk factors if their measurements exceeded cutoffs that were determined on the basis of national recommendations. We analyzed the prevalence of risk factors by sex and age and compared the age-adjusted prevalence with 1999-2004 NHANES measurements.

Results: EARTH participants were significantly more likely than NHANES participants to be overweight or obese and to have impaired fasting glucose, low high-density lipoprotein cholesterol, high low-density lipoprotein cholesterol, and hypertension. The prevalence of high total cholesterol and triglycerides was not significantly different between the 2 study populations.

Conclusion: We provide baseline clinical measurements for chronic disease risk factors for a larger study sample than any previous study of AI/AN living in Alaska. The prevalence of most risk factors measured exceeded national rates. These data can be used to tailor health interventions and reduce health disparities.

Figure 1

Age-adjusted prevalence of dyslipidemia for Alaska EARTH Study participants, 2004-2006, compared with Alaska NHANES participants, 1999-2004. Error bars represent 95% confidence intervals. Direct age standardization is based on the 2000 census standard population for adults aged 20 years or older using age groups 20 to 34 years, 35 to 44 years, 45 to 54 years, 55 to 64 years, and 65 years or older. Clinical risk factor categories for EARTH Study participants are based on recommendations from the National Cholesterol Education Program (11). Clinical risk factor categories for NHANES participants are based on Health, United States, 2007 (16), Hyre et al (19), and Kuklina et al (20). Abbreviations: EARTH, Education and Research Towards Health; NHANES, National Health and Nutrition Examination Survey; LDL, low-density lipoprotein; HDL, high-density lipoprotein.

Figure 2

Age-adjusted prevalence of clinical risk factors for Alaska EARTH Study participants, 2004-2006, compared with Alaska NHANES participants, 1999-2004. Error bars represent 95% confidence intervals. Direct age standardization is based on the 2000 census standard population for adults aged 20 years or older using age groups 20 to 34 years, 35 to 44 years, 45 to 54 years, 55 to 64 years, and 65 years or older. Clinical risk factor categories for EARTH Study participants are based on recommendations from the American Diabetes Association and the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (12,13). Clinical risk factor categories for NHANES participants are based on Health, United States, 2007 (16) and Cowie et al (17). Abbreviations: EARTH, Education and Research Towards Health; NHANES, National Health and Nutrition Examination Survey.