Heart disease mortality among Alaska Native people, 1981-2007

OBJECTIVES: Historically Alaska Native (AN) people have exhibited low overall rates of heart disease mortality compared to the US white (USW) population. This study compares AN and USW heart disease mortality rates during the 27 year period from 1981 to 2007. METHODS: AN and USW heart disease mortality rates were compared overall and separately by sex, age, and disease subtype. Age-adjusted rates were calculated for three nine year periods between 1981 and 2007 and compared to the USW rates. RESULTS: AN people age 35 years and older had a significantly lower rate of heart disease mortality compared to USW people (Rate Ratio (RR) = 0.80). The lower overall rate was due primarily to a lower ischemic heart disease mortality rate (RR=0.63). Overall heart disease mortality has declined over the 27 year study period for both AN (33.1%) and USW (35.0%) populations. However, hypertensive heart disease mortality increased 155.2% for AN and 13.7% for USW people. Age-specific heart disease mortality is approximately 20% lower for AN people age 75 years or older compared to USW people while it is virtually identical for the two groups between the ages of 35 and 74 years. CONCLUSIONS: The age-adjusted AN heart disease mortality rate has been consistently about 20% lower than the USW rate from 1981 through 2007, with similar AN:USW rate ratios for men and women. However, combining all ages and all heart disease subgroups into a single age-adjusted statistic obscures many important differences across ages and disease subtypes.