Abstract 4984: Trends in 10-year Risk of Incident Cardiovascular Disease in the United States, 1972–2004
Background: The significant bidirectional changes in cardiovascular(CV) risk factor prevalence make the net trend in incident CV risk unknown. We assessed the trends in the net 10-year risk for incident CV disease using the Framingham risk model and data from the National Health and Nutrition Examination Surveys(NHANES).
Methods: We used data from NHANES II (1976–1980), NHANES III (1988–1994), and NHANES 1999–2004, including major CV risk factors, all collected in a standardized manner. People with a history of CV disease, pregnant women, people with missing data and those outside the Framingham age range were excluded. The Framingham risk function estimated the 10-year risk for CV disease. The slope of change or rate of change per year between NHANES II/III, and between NHANES III/1999–2004 were determined. The slope difference was calculated and compared to zero.
Results: The mean age-adjusted 10-year CV risk decreased from 10 to 7.9% between NHANES II and III, with a significant slope (p<0.001). However, the mean age-adjusted risk decreased to a lesser extent between NHANES III and NHANES 1999–2004 from 7.9 to 7.4% (p<0.001). The slopes were different (p<0.001). In women, CV risk did not change between NHANES III and 1999–2004, 7.9 to 7.5%, (p=0.40). Predicted 10-year risk by age group (Figure⇓) shows that the decrease in CV risk was lower in the second period compared to the first one in all age groups, except in the elderly.
Conclusion: The estimated net risk for CV disease in the US population decreased from 1976–1980 to 1988–1994 but minimally changed from 1988–1994 to 1999–2004, particularly in women. The increased prevalence of obesity may have offset the gain in CV risk reduction.