Ideal CV Health Over the Long Term Linked With Better Survival, Less Disease

(UPDATED) More time spent in ideal cardiovascular health, starting as early as childhood, is associated not only with less subclinical atherosclerosis, but also with significant improvements in cardiometabolic health and a lower risk of all-cause mortality, according to the results of two new studies published this week in JAMA Cardiology.

In the first study, which was led by Vanessa Xanthakis, PhD (Boston University School of Medicine/Framingham Heart Study, MA), and Laura Corlin, PhD (Tufts University School of Medicine, Boston), the authors showed that a longer duration of ideal or intermediate CV health in midlife was associated with a lower risk of developing hypertension, diabetes, chronic kidney disease, cardiovascular disease, and all-cause mortality when compared with people who had poor CV health in the Framingham Heart Study.

“You don’t have to be perfect, but every step counts; the closer you get to an ideal CV health through lifestyle changes, the lower your risk of disease,” Xanthakis told TCTMD. 

Norrina Bai Allen, PhD (Northwestern University Feinberg School of Medicine, Chicago, IL), and colleagues took a different approach in their study but showed similar findings. In their analysis, they found that people who started in ideal CV health in childhood and stayed healthy throughout middle age had less subclinical atherosclerosis compared with those whose CV health declined rapidly after childhood or children who began with a less-than-ideal CV risk profile. To TCTMD, Allen said she and her team were surprised at how quickly CV health declined in some of the young participants, noting that the “early decliners” had a downward progression that began much earlier than anticipated.

It’s not just where you start, it’s how fast you lose your cardiovascular health that’s really important as well. Norrina Bai Allen

“The rate at which you lose your cardiovascular health seems to play a particularly important role,” she said. “If you look at groups that started off at about the same level of CV health, those that declined more rapidly and earlier had a greater risk [for subclinical atherosclerosis] on carotid [intima-media thickness (IMT)]. So it’s not just where you start, it’s how fast you lose your cardiovascular health that’s really important as well.”

In an editorial, Erica Spatz, MD (Yale School of Medicine, New Haven, CT), writes that both studies add to the “growing recognition that assessing longitudinal cardiovascular health is critical for identifying populations at risk for future cardiovascular disease and informing primordial and primary prevention efforts.” These papers, she says, show that “from childhood through middle and even late adulthood, maintaining good cardiovascular health pays off.”   

Life’s Simple 7

In 2010, the American Heart Association created a CV health score based on Life’s Simple 7 that represents a summary burden of a person’s CV risk factors and lifestyle metrics. The CV health score defines people as having ideal, intermediate, or poor CV health based on their blood pressure, glucose levels, weight, cholesterol levels, adherence to a healthy diet, physical activity levels, and smoking status. Studies have shown that very few US adults—somewhere in the range of 5% to 10%—are in ideal CV health, and that percentage decreases further as people age.

While higher CV health scores have also been shown to be associated with a lower risk of diabetes, CVD, and all-cause mortality, little is known about the maintenance of CV health over longer periods of time.

To address this question, Xanthakis, Corlin, and colleagues identified 1,445 participants (mean age 60 years; 52% women) from the Framingham Offspring Study who attended examination cycles 5, 6, and 7 (1991-1995, 1995-1998, and 1998-2001, respectively) and compared outcomes of participants between those who spent 5 additional years in ideal or intermediate CV health and those in poor CV health. Overall, the vast majority of the participants had poor or intermediate CV health, with just 7% of subjects in ideal CV health.

After adjusting for age and sex, each 5-year period that participants lived in ideal or intermediate CV health was associated with significantly better cardiometabolic measures, as well as a lower risk of all-cause mortality, when compared with those in poor CV health. In terms of secondary endpoints, each 5-year period spent in ideal/intermediate CV health was also associated with a significantly lower risk of coronary heart disease, stroke, congestive heart failure, and peripheral arterial disease.

Association of Intermediate/Ideal Versus Poor CV Health for 5 Years in Midlife

^aStroke, TIA, MI, coronary insufficiency, angina, intermittent claudication, or heart failure.

“For example, with regards to physical activity, one of the components of Life’s Simple 7, people might be more active in the summer but hibernate in the winter,” said Xanthakis. “We decided to use 5-year increments so we could better capture lifestyle behavior. We want to emphasize that the longer you keep yourself in a healthy cardiovascular state, the lower your chance of getting diseased.”

In terms of public health, Xanthakis said the implications could be great. “Quantifying these associations may help us understand that when you make even small healthier changes in your lifestyle and maintain them for a longer period, you could gain years of a healthier life,” she said, stressing that every little healthier change matters. “We are [also] extremely thankful to all Framingham Heart Study participants for dedicating their precious time so we could have such comprehensive data to evaluate our hypotheses.”

She pointed out that Framingham is a relatively healthy cohort, which means that the beneficial effects of time spent in good CV health may be amplified among those with underlying health conditions. To facilitate changes at the community level, Xanthakis said every person should know their numbers—weight, blood pressure, cholesterol levels, and glucose levels—so that they can focus on making the right improvements. “Clinicians and public health professionals should also focus on educating the community on the importance of achieving those good numbers,” she advised.

How Fast Does CV Health Decline and Does It Matter?  

In the second study, Allen and colleagues sought to assess the longitudinal trajectories of CV health and the impact declines in CV health had on subclinical atherosclerosis. To do so, they turned to five prospective studies with childhood and young adulthood cohorts, including the Cardiovascular Risk in Young Finns Study (YFS), Bogalusa Heart Study (BHS), Project HeartBeat!, the Special Turku Coronary Risk Factor Intervention Project (STRIP), and the Coronary Artery Risk Development Study (CARDIA).

The researchers calculated a “clinical” CV health score based on measures of body mass index, blood pressure, blood glucose, and total cholesterol levels. They also performed a second analysis using the full Simple 7 metrics—the aforementioned clinical measures plus smoking status, diet, and physical activity levels—to create the full CV health score, but this was an exploratory analysis because participant data were only available at three or more examinations in YFS, CARDIA, and Project HeartBeat!.

In total, 1,518 participants had a high CV health score at 8 years of age that was maintained through early adulthood, while there were 2,403 and 3,066 participants with high CV health scores in childhood that experienced moderate or early declines in their CV health. For those with a moderate decline, the drop-off in CV health occurred around at 25 to 30 years while those with an early decline saw their CV health deteriorate in their teens or early 20s. The two remaining groups were roughly 2,500 subjects with intermediate CV health in childhood that declined early or later in life.

“None of our groups were able to maintain ideal cardiovascular health throughout childhood and young adulthood,” said Allen, a finding the group said wasn’t surprising, although it was disheartening. “We did find a significant proportion of children who maintained fairly high levels and then started to decline towards middle age. The most surprising finding to us was that already by age 8, which was the youngest age included in this cohort, there was a significant group of children, around 20%, who were no longer in ideal cardiovascular health.”

Overall, the trajectory of the clinical CV health score was associated with continuous carotid IMT in adulthood. After adjusting for demographic and baseline smoking, physical activity, and diet, those with a high CV health score who declined later in life had the thinnest carotid IMT while those in intermediate CV health with an early decline had the thickest (0.64 vs 0.72mm, respectively; P < 0.001). In a comparison with the high CV score/late decline trajectory, those with the earliest declines in CV health, regardless of their CV health at baseline, were significantly more likely to have “high” carotid IMT levels. Similar results were observed when investigators calculated the CV health trajectory of subjects using all seven risk factors. 

“I think every year you can prevent poor levels of these risk factors is added benefit to reducing your risk of cardiovascular disease, but many of us strongly believe that protecting ideal levels is probably the most effective way to reduce cardiovascular risk or to eliminate it potentially,” said Allen. “One, you haven’t accumulated any subclinical damage due to elevated risk factors. Two, I also just think it’s easier to maintain a good behavior, like a healthy diet or physical activity, than it is to change once someone has started eating poorly or stopped exercising.”

Spatz, in her editorial, notes that people’s willingness to make changes to their lifestyle depends on their perception of how vulnerable they might be. Young people, where death and disease are many years off, may be less likely to act on health issues within their control because the threats are less certain or more distant. However, these two new studies could provide an impetus for capturing people’s experiences and behaviors throughout the life span. In doing so, it may be possible to change their perceptions about prevention by “incorporating cumulative cardiovascular health metrics and health trajectories.”

Note: This story was updated with additional comments from Xanthakis.