Risk factors for cardiovascular disease may increase over 65

New findings suggest that all adults, including those over 65, should be mindful of risk factors for cardiovascular disease. The results, published in the Journal of the American Geriatric Society, are part of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, which looks at stroke incidence in approximately 30,000 individuals. The REGARDS study is funded by the National Institutes of Health's National Institute of Neurological Disorders and Stroke (NINDS).

"As life expectancy continues to increase, we need to improve risk factor prevention and management for stroke and heart disease across the lifespan, including for those adults over the age of 65," said Claudia Moy, Ph.D., acting director of the Office of Clinical Research at NINDS, and one of the study authors. "The latest findings from the REGARDS study reveal that no age group is immune to risk factors related to cardiovascular disease and that prevention efforts should target all adults."

In the current study, led by George Howard, Dr.PH, a biostatistics professor at the University of Alabama at Birmingham, researchers examined individuals over the course of 10 years to determine how many developed risk factors known to be associated with stroke and heart disease. The specific risk factors that the researchers focused on in the current study were high blood pressure, diabetes mellitus, high cholesterol and atrial fibrillation, a type of problem with heart rate and rhythm that is greatly associated with stroke. The authors noted that while smoking is also a risk factor for stroke and heart disease, it is uncommon for individuals to begin smoking after the age of 30.

The REGARDS study is made up of a sample of black and white Americans, with more than half of the participants living in the Stroke Belt, an area of the southeastern U.S. where stroke mortality is higher than in the rest of the country.

Dr. Howard's team discovered that development of cardiovascular disease risk factors remains high among adults older than 65. The study also confirmed large racial disparities in the incidence of high blood pressure, diabetes mellitus, high cholesterol, and atrial fibrillation.

Overall, nearly half of the participants whose blood pressure was normal at the beginning of the study went on to develop high blood pressure during the nearly 10 years of follow-up. Across all age groups, including participants older than 75, black men had a 24 percent greater risk of developing high blood pressure compared to white men. Black women aged 45 to 54 had a 93 percent higher risk of developing high blood pressure than did white women. However, that racial disparity shrank among women older than 75, because in that age group, incidence of high blood pressure continued to increase in white women while remaining stable among black women. The findings suggest that efforts to prevent high blood pressure may be beneficial in all subgroups.

As study participants got older, their risk of developing diabetes mellitus decreased, although a large racial disparity was seen across all age groups. Overall, compared to whites, black men were 52 percent and black women were 114 percent more likely to develop diabetes mellitus.

The incidence of high cholesterol increased through age 74, then decreased slightly among participants older than 75. Among all age groups, Dr. Howard's team found that there was at least a 20 percent risk of developing high cholesterol and that the incidence for blacks was greater than for whites. The researchers also discovered that risk of atrial fibrillation increased as participants got older, with whites more likely to develop the condition than blacks.

"In addition to improving treatment and control of potent risk factors for stroke and heart disease, finding ways to prevent development of those risk factors may be a potential strategy to lower rates of cardiovascular disease across the age span, but especially in black Americans," said Dr. Moy.

Earlier this year, the NINDS launched a stroke prevention campaign called Mind Your Risks, designed to educate people aged 45-65 about the link between uncontrolled high blood pressure and the risk of having a stroke or developing dementia later in life.

This study emphasizes the importance of providing evidence-based clinical preventive services to adults 65 years and older. The U.S. Preventive Services Task Force has recommendations on healthful diet and physical activity, screening for diabetes and lipid disorders and use of aspirin to prevent CVD in patients who are at increased risk. See the Task Force website for specific recommendations.