After two decades of improvement, the percentage of Americans without major heart disease risk factors is dropping, according to a report in Circulation: Journal of the American Heart Association. “From a preventive health point of view, it’s important that individuals achieve as many of these goals as possible, and it’s disappointing that less than 10 percent of Americans are meeting them all,” said Earl S. Ford, M.D., M.P.H., lead author of the study and medical officer of the U.S. Public Health Services at the Centers for Disease Control and Prevention (CDC) in Atlanta, Ga.
“Our analysis suggests that achieving low risk status for most U.S. adults remains a distant and challenging goal. Unfortunately, the limited strides that were made towards this goal during the 1970s and 1980s were eroded by the increases in excess weight, diabetes and hypertension during more recent decades.” Researchers tracked data on adults aged 25-74 in four national surveys, examining several low-risk criteria:
Never or former smoker; Total cholesterol below 200 milligrams per deciliter (mg/dL) and not using cholesterol-lowering drugs; Blood pressure below 120/80 millimeters of mercury (mmHg) without using blood pressure-lowering medication; Not overweight or obese, as reflected in a body mass index (BMI) less than 25 kg/m2; and Never diagnosed with diabetes. In numerous studies, people without risk factors have lower healthcare costs and are far less likely to develop cardiovascular disease.
In the National Health and Nutrition Examination Surveys (NHANES): 4.4 percent of adults had all five of the low-risk factors in NHANES I, 1971-75; 5.7 percent had all five in NHANES II, 1976-1980; 10.5 percent of adults rated low risk on all factors in NHANES III, 1988-94; and only 7.5 percent of adults rated low risk on all factors in the 1999-2004 survey. “Until the early 90s, we were moving in a positive direction, but then it took a turn and we’re headed in a negative direction,” Ford said. “When you look at the individual factors, tobacco use is still headed in the right direction and so are cholesterol levels, although that has leveled off. The problem is that blood pressure, BMI and diabetes are all headed in the wrong direction.”
An imbalance in the amount of energy consumed in food and the amount expended in physical activity is likely a major culprit in the negative risk factor trends, Ford said. “Addressing this imbalance, by people becoming more active and eating less, would reduce overweight and obesity which in turn would help to lower blood pressure and prevent diabetes,” Ford said. The trends over time are similar in men and women, although in every survey significantly more women than men had across-the-board low risk factors.
Furthermore, whites had a significantly higher prevalence of low risk factors than African Americans in all but one survey (1976-1980). A larger percentage of whites had a low risk factor burden compared to Mexican Americans during 1988-1994 and 1999-2004 surveys. Results of the study illustrate a great need for prevention, “thus, healthcare providers should have adequate resources, time and reimbursement to engage in the prevention of cardiovascular disease in patients,” researchers said. “Such efforts by clinicians need to be complemented by efforts by state and national agencies that have the responsibility to develop effective public health interventions.”
Potential targets for such interventions include work sites and schools where large numbers of people can be targeted and where evidence-based interventions can be implemented. In an accompanying editorial, Rob M. van Dam, Ph.D. and Walter C. Willett, M.D., Ph.D. of Harvard Medical School and Brigham and Women’s Hospital said the findings are disturbing because the trends among younger age groups have occurred in the presence of unprecedented availability of evidence-based heart disease treatment and even more worrisome because the trends do not yet reflect the effects of the current epidemic of childhood obesity.
The findings provide an important signal that the health of Americans is at a crossroad, they noted. “Much potential exists to reverse ominous trends in cardiovascular risk factors and mortality in the United States, but this is unlikely to occur without making prevention of overweight and obesity a clear national priority.”
Ford’s co-authors are: Chaoyang Li, M.D., Ph.D.; Guixiang Zhao, M.D., Ph.D.; William S. Pearson, Ph.D.; and Simon Capewell, M.D.
Adapted from materials provided by American Heart Association.