Trends in Cardiovascular Risk Factor Levels in the Minnesota Heart Survey (1980-2002) As Compared with the National Health and Nutrition Examination Survey (1976-2002): A Partial Explanation for Minnesota's Low Cardiovascular Disease Mortality?

The authors compared trends in and levels of coronary heart disease (CHD) risk factors between the Minneapolis-St. Paul, Minnesota, metropolitan area (Twin Cities) and the entire US population to help explain the ongoing decline in US CHD mortality rates. The study populations for risk factors were adults aged 25-74 years enrolled in 2 population-based surveillance studies: the Minnesota Heart Survey (MHS) in 1980-1982, 1985-1987, 1990-1992, 1995-1997, and 2000-2002 and the National Health and Nutrition Examination Survey (NHANES) in 1976-1980, 1988-1994, 1999-2000, and 2001-2002. The authors found a continuous decline in CHD mortality rates in the Twin Cities and nationally between 1980 and 2000. Similar decreasing rates of change in risk factors across survey years, parallel to the CHD mortality rate decline, were observed in MHS and in NHANES. Adults in MHS had generally lower levels of CHD risk factors than NHANES adults, consistent with the CHD mortality rate difference. Approximately 47% of women and 44% of men in MHS had no elevated CHD risk factors, including smoking, hypertension, high cholesterol, and obesity, versus 36% of women and 34% of men in NHANES. The better CHD risk factor profile in the Twin Cities may partly explain the lower CHD death rate there.