The American Heart Association has released an assessment tool called Life’s Simple 7 that focuses on modifiable health behaviors, which can be used to promote cardiovascular health. Previously researchers have shown a relationship between cardiovascular problems and a greater risk of cognitive decline. In light of the earlier research, researchers wondered whether scores on Life’s Simple 7 could be associated with a greater risk of cognitive decline. If so, this association of decline with a tool focused on modifiable health behaviors could provide motivation for making lifestyle changes that will benefit the heart and brain.
To examine this question, researchers looked at data from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. A total of 17,761 individuals took part in this study. Participants were all over 45 years old and had normal global cognitive status at the start of the study. Of the participants, 45 percent were men and 42 percent were African American. (The other 58 percent were Caucasian.) The average age of the participants at the beginning of the study was 64.
Each participant was given a Life’s Simple 7 assessment, which covered the following modifiable areas of health: smoking, diet, physical activity, body mass index (BMI), blood pressure, total cholesterol, and fasting glucose. Scores on Life’s Simple 7 can range from 0 to 14, with a higher score indicating better cardiovascular health. Overall, Caucasian participants had an average score of 7.9, and African American participants’ average score was 6.9. Males and individuals with higher education and higher income were more likely to have high scores. For the data analysis, researchers divided the study participants into thirds based on their scores. The lowest third had scores between 0 and 6, the middle third had scores of 7 to 8 and the top third had scores between 8 and 14.
Four years after the beginning of the REGARDS study, participants’ degree of cognitive status was assessed using measures of verbal learning, memory, and fluency. At that point, 573 of the participants were judged to have developed mild cognitive impairment. These individuals were more likely to have lower incomes, to reside in the Southeast of the United States (in what is known as “the stroke belt”), and to have been diagnosed with cardiovascular disease.
When looking at the relationship between Life’s Simple 7 and cognitive impairment, the researchers found that the participants in the group with the lowest scores on the cardiovascular health measures had significantly greater rates of cognitive impairment compared to the intermediate and high score groups. Of those individuals with low scores, 4.6 percent showed cognitive impairment four years later, compared to 2.7 percent in the intermediate group and 2.7 percent of the high score group. This translates to a 35 percent and 37 percent lower risk of cognitive impairment for the intermediate and high score groups. This association was similar across race, gender, age, levels of education, and geographic regions. When the researchers looked at the specific cardiovascular risk factors that make up Life’s Simple 7, they found that the strongest associations with cognitive impairment came from smoking, BMI, and fasting glucose.
Overall, the findings of this study are encouraging in that they convincingly demonstrate that aspects of cardiovascular health that are modifiable through lifestyle changes and medical treatment are related to risk of cognitive impairment. This communicates that cognitive impairment is not inevitable, and that controllable cardiovascular risk factors play a significant role in the risk for cognitive impairment. The researchers also note that the lack of significant differences between the intermediate and high score groups “is an encouraging message for population health promotion, because intermediate CVH [cardiovascular health] is a more realistic target than ideal CVH for many individuals.e
Thacker EL, Gillett SR, Wadley, VG, et al. The American Heart Association Life’s Simple 7 and incident cognitive impairment: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Journal of the American Heart Association. (2014). DOI: 10.1161/JAHA.113.000635