Megan Brooks

November 05, 2012

The risk of developing cardiovascular disease (CVD) in one's lifetime after age 45 years exceeds 60% for men and 55% for women overall, a new study suggests.

Not surprisingly, the risk is greatest in people with more CVD risk factors, the study team says. However, lifetime CVD risk still tops 30% in men and women even with an optimal risk factor profile.

Still, keeping traditional CVD risk factors at bay in midlife leads to substantially longer survival free of CVD, they found, up to 14 years longer than those with 2 risk factors.

The study appears in the November 7 issue of the Journal of the American Medical Association, a theme issue on cardiovascular disease. It was released early online November 5 to coincide with the American Heart Association's 2012 Scientific Sessions underway in Los Angeles, California.

No Data

Until now, there have been no published data on the lifetime risk for total CVD, John T. Wilkins, MD, from the Northwestern University Feinberg School of Medicine in Chicago, Illinois, and colleagues note in their paper. "Estimates of lifetime risk for total…CVD may provide projections of the future population burden of CVD and may assist in clinician-patient risk communication," they write.

In this study, the researchers estimated lifetime risk, as well as years lived free of total CVD (including fatal and nonfatal coronary heart disease, all forms of stroke, congestive heart failure, and other CVD deaths) using individual-level data from 5 National Heart, Lung, and Blood Institute–funded community-based cohorts: the Framingham Heart Study, Framingham Offspring Study, Atherosclerosis Risk in Communities Study, Chicago Heart Association Detection Project in Industry Study, and Cardiovascular Health Study.

The analysis included as many as 905,115 person-years of data. All participants were free of CVD at baseline.

Across all index ages (ie, 45, 55, 65, and 75 years), 1.7% to 7.9% of individuals were in the "all optimal" risk factor group: that is, those with blood pressure [BP] less than 120/80 mm Hg, total cholesterol [TC] level < 180 mg/dL, and no smoking or diabetes.

At all index ages, more than 55% of individuals were in the 1 major or at least 2 major risk factor strata, including those with a BP of 160/100 mm Hg or greater or receiving treatment, TC level of 240 mg/dL or greater or receiving treatment, diabetes mellitus, and/or current smoking.

No Guarantees

At some time during follow-up across all index age groups, approximately 30% to 35% of individuals experienced CVD events, with men at higher risk than women.

Table. Lifetime CVD Risk Estimates by Sex and Index Age

Index Age (y)
Risk in Men (95% CI) (%) Risk in Women (95% CI) (%)
45 60.3 (59.3 – 61.2) 55.6 (54.5 – 56.7)
55 60.2 (59.1 – 61.2) 56.3 (55.2 – 57.4)
65 59.0 (57.6 – 60.4) 56.1 (54.7 – 57.5)
75 54.5 (52.2 – 56.9) 52.3 (50.3 – 54.3)

CI = confidence interval.

When stratified by risk factor burden, at ages 55 and 65 years, men and women with at least 1 elevated risk factor (BP 140-149/90-99 mm Hg or TC 200-239 mg/dL, but no diabetes or smoking), 1 major risk factor, or at least 2 major risk factors, had lifetime risks of CVD (to age 95 years) that exceeded 50%.

Even with an optimal risk factor profile, men and women at the index age of 55 years had a lifetime CVD risk of greater than 40% and 30%, respectively. However, for those in the optimal risk factor group in middle age, the age at onset of CVD was an average of 8 to14 years later than that of their peers with at least 2 major risk factors.

"Thus, the maintenance of optimal risk factors through ages 45, 55, and 65 years may not guarantee a life free from total CVD, but it increases the probability that more years will be lived free of CVD," the researchers note.

"In addition, for some index ages in men and women in our analyses, we observed that individuals with optimal risk factors who developed total CVD at much older ages, appeared to have a shorter post-CVD event survival, consistent with the phenomenon of compression of morbidity," posited in 1980 by Fries et al (N Engl J Med. 1980;303:130-135).

The finding of a substantial lifetime CVD risk even among individuals with an optimal risk factor profile highlights "the large public health burden and opportunities for prevention of total CVD," the authors conclude.

The study was funded by the National Heart, Lung, and Blood Institute. The authors have disclosed no relevant financial relationships.

JAMA. 2012;308:1795-1801. Published online November 5, 2012. Abstract

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