Adherence to Healthy Habits Linked to Years Free of Chronic Disease

Adherence to four heart-healthy lifestyle factors is associated with an increase in the number of life-years spent without any major chronic conditions, including coronary heart disease, stroke, and type 2 diabetes, according to the results of a new study.

In an analysis of 116,043 people from 12 European cohorts, there was a linear relationship between the overall healthy lifestyle score and the number of disease-free years, report Solja Nyberg, PhD (University of Helsinki, Finland), and colleagues in their paper published April 6, 2020, in JAMA Internal Medicine. Each 1-point increase in the 8-point healthy lifestyle score was associated with an increase of 0.96 disease-free years in men and 0.89 disease-free years in women.

“Our results provide powerful evidence that differences in lifestyle are associated with large differences in health span,” Nyberg told TCTMD via email. “A high overall healthy lifestyle score was associated with significant gains in years lived without major noncommunicable diseases between ages 40 and 75 years in both sexes. Comparing the best with the worst lifestyle score was associated with approximately 9 additional years without chronic diseases.”

Nyberg said that while it’s well known that a healthy lifestyle protects against several major noncommunicable diseases, the benefit is typically quantified as relative risk estimates for specific diseases. There was some uncertainty, she said, over the impact of a healthy lifestyle on disease-free life expectancy.

To address this, the group turned to the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) consortium. Of the 19 cohorts that are part of the IPD-Work consortium, 12 had data on the four risk factors in question—body mass index (BMI), smoking status, leisure-time physical activity, and alcohol consumption—at baseline and follow-up of noncommunicable diseases (coronary heart disease, stroke, type 2 diabetes, cancer, asthma, and chronic obstructive pulmonary disease). An aggregate lifestyle score was calculated based on optimal (2 points), intermediate (1 point), or poor (0 points) adherence to each of the four lifestyle factors. The mean age of participants was 43.7 years, and 61.1% were women.

After a mean follow-up of 12.5 years, 17.8% of men and 13.2% of women developed at least one incident chronic disease. For men with 0 points on the lifestyle score, they had an estimated 21.7 years free from chronic disease between ages 40 to 75 years while men with the maximum score had 30.9 disease-free years. In women, those with the lowest possible score had 21.6 disease-free years between ages 40 to 75 years compared with 30.7 years free of chronic disease in those with the optimal lifestyle score. Men and women with the maximum lifestyle score reached 70.9 and 70.7 years, respectively, without any of the six noncommunicable diseases.

When investigators defined the number of disease-free years to include heart failure and dementia in addition to the six noncommunicable diseases, the results did not change substantially.  

To TCTMD, Nyberg said a normal BMI appears to be a particularly important component of the lifestyle profiles. Given the four lifestyle factors, there were 16 different lifestyle profiles possible based on the combinations; of these combinations, the four associated with the longest disease-free lifespan included a normal BMI and at least two of the remaining three lifestyle factors, she said.