Patients without obesity, diabetes or hypertension at age 45 lived 10 years longer on average without heart failure, and 13 years longer overall than those with all three conditions, according to a Northwestern Medicine study.
The study is the first time scientists have quantified the average number of healthy years gained by avoiding specific heart failure risk factors in middle age.
Faraz Ahmad, MD, a senior fellow in cardiovascular disease, was the lead author of the study, published in the Journal of the American College of Cardiology: Heart Failure. John Wilkins, MD, ’11 MS, ’12 GME, assistant professor of Medicine in the Division of Cardiology and of Preventive Medicine, was the senior author.
While it’s long been known that diabetes, obesity and hypertension are key risk factors for heart failure — a condition where the heart is no longer able to adequately pump blood to the rest of the body — risk estimates have traditionally been presented in terms of percentages.
Ahmad’s objective was to create a novel way to communicate heart failure risk — one that could potentially be more impactful with patients and public health officials. He was inspired by a 2012 study Wilkins published in JAMA, which showed that those without risk factors in middle age lived up to 14 years longer free of cardiovascular disease than those with at least two risk factors.
In the current study, Ahmad, Wilkins and other Northwestern Medicine investigators pooled data from four large cohort studies conducted across the country. They found that the absence of obesity, diabetes and hypertension at ages 45 and 55 was associated with up to 86 percent lower risk of heart failure throughout the rest of the patient’s life.
The authors were also able to quantify the average additional years men and women lived free of heart failure, as well as overall survival, with the absence of one, two or three risk factors at age 45 and age 55. Of the three risk factors, the absence of diabetes at midlife was associated with the most years lived heart failure-free.
“Because we had such a large data set, we were able to quantify how the absence of risk factors leads to years lived free of heart failure, as opposed to just a risk for heart failure,” Ahmad said. “And we think having the actual number is much more meaningful.”
The hope is that such figures will better illuminate the benefits of avoiding obesity, diabetes and hypertension to patients and potentially lead to stronger compliance with medications and lifestyle.
“In my clinical practice, I find these data, and data like it, to be very helpful in counseling patients. For most people, what they really want to know is ‘how long on average am I expected to live, and how long am I expected to live healthy?’” Wilkins said. “Faraz was able to quantify this in a very direct way. And I find it motivating: live as long as you can without developing these risk factors and the benefits can be substantial.”
In future research, the investigators are interested in studying how communicating risk to patients leads to measurable improvements in the prevention of risk factors and the overall incidence of heart failure.
“Once someone has heart failure, we have limited therapies for it. On average, the five-year survival may be as low as 50 percent,” Ahmad said. “So preventing the development of heart failure is really key if you want to move the needle on this massive public health problem.”
The paper was also co-authored by Hongyan Ning, MD, MS, statistical analyst in the Department of Preventive Medicine; Jonathan Rich, MD, assistant professor of Medicine in the Division of Cardiology; Clyde Yancy, MD, MSc, chief of Cardiology; and Donald Lloyd-Jones, MD, ScM, chair of the Department of Preventive Medicine.
The research was supported in part by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health grant R21 HL085375 and award T32HL069771, as well as the Heart Failure Society of America.