The Role of Healthy Lifestyles in Healthy Aging

“Healthy aging” refers to both the quality and quantity of life—adding life to our years and years to our life. The anthropologist Ashley Montagu once said, “The best way to age is to die young as late as possible.” Living longer without illness is a goal for most people. Healthy aging is influenced by genetics, as well as by lifestyle factors such as being physically active, not smoking, and maintaining body weight within a normal range.

Cardiorespiratory (aerobic) fitness is associated with both longevity and the reduction of chronic diseases, such as heart disease. In a new observational study, funded in part by the National, Heart, Lung, and Blood Institute (NHLBI), researchers examined the associations between cardiorespiratory fitness and the development of nonfatal chronic conditions or death. The study linked data from participants in the Cooper Center Longitudinal Study (CCLS) who underwent standardized treadmill fitness testing with data from Medicare claims when these participants reached age 65 years and older. The researchers found that cardiorespiratory fitness, as objectively measured at middle age, was significantly associated with a lower risk of developing chronic disease decades later.

Diane Bild, M.D., M.P.H., Associate Director for the Prevention and Population Sciences Program, Division of Cardiovascular Sciences at the NHLBI, wrote an editorial to accompany the publication. In the answers below, Dr. Bild discusses healthy aging, the importance of the study, and what research is in progress.

How do you define healthy or “successful” aging?

I use a common sense definition rather than a formal one, though formal definitions are needed for research studies and making policy for seniors. The basic concept of healthy aging is to age without chronic illness and disability. Another approach is to think of healthy aging as maintaining well-being in all spheres of life—physical, mental, and social.

What is the role of lifestyle in contributing to healthy aging?

One research study supported by the NHLBI and conducted in a large group of elderly people identified the following factors as being associated with remaining healthy: higher physical activity levels, refraining from cigarette smoking, having a lower waist circumference, and having lower blood pressure. The basic tenets of a healthy lifestyle apply to achieving these—a healthy diet, regular physical activity, and avoiding stress.

What is the importance of cardiorespiratory fitness?

Several studies have found that cardiorespiratory fitness, as measured by performance on a treadmill, is associated with longevity and prevention of cardiovascular disease. A recent study also found that people who performed better on treadmill machines (were able to run longer, even after progressively higher inclines) appeared to avoid a wide range of chronic illnesses.

What are the key findings in the recent study “Midlife fitness and the development of chronic conditions in later life” in the Archives of Internal Medicine?

The authors studied 18,670 men and women who visited the Cooper Clinic from 1970 to 2009 and underwent standardized treadmill fitness testing. The participants were followed through Medicare claims after they reached age 65. After adjusting for age, body mass index, systolic blood pressure, total cholesterol, smoking, fasting blood glucose, and alcohol intake, there was a strong graded relationship of fitness to the rate of development of a set of common chronic conditions, including ischemic heart disease, heart failure, stroke, diabetes, chronic obstructive pulmonary disease, chronic renal disease, Alzheimer’s dementia, and cancer. That is, the greater the fitness level, the lower the rates of chronic conditions. Fitness appeared protective against each chronic condition, and there were similar relationships in both men and women.

What are the key strengths and limitations of this study?

Its large size and long duration are major strengths, as well as the objective measure of fitness. As an observational study, however, we always worry about confounders—other factors that could explain the findings. One such factor is genetics, which can both influence the ability to attain a high level of fitness and be associated with a longer life and avoidance of disease.

What are the take-home messages for health care professionals?

Health care professionals can feel a bit more confident about encouraging their patients to get regular exercise. This may have an impact on a wide variety of diseases and conditions that people want to avoid.

What research is currently being done to address the importance of healthy lifestyles in aging?

The NHLBI supports a variety of studies that measure physical activity, and scientists are looking for associations with risk factors and health outcomes. One very exciting study supported by the National Institute on Aging and the NHLBI should provide direct evidence on whether exercise contributes to healthy aging in older people. It is called the Lifestyle Interventions and Independence for Elders (LIFE) trial. This multicenter randomized controlled trial compares a moderate-intensity physical activity program with a successful aging health education program in 1,600 sedentary older persons for an average of 2.7 years. While the primary outcome is major mobility disability, many chronic disease outcomes relevant to healthy aging, such as cognitive impairment, will be examined.

Resources

Health Information

• Health Topics: Atherosclerosis, Coronary Heart Disease Risk Factors, High Blood Pressure, How the Heart Works, Overweight and Obesity, Physical Activity and Your Heart, Smoking and Your Heart 
• Aim for a Healthy Weight: Assessing Your Weight and Health Risk
• In Brief: Your Guide to Physical Activity and Your Heart (4 page booklet)
• Your Guide to Physical Activity and Your Heart (48 page booklet)

Research

• Willis, B.L., Gao, A., Leonard, D., Defina, L.F., and Berry, J.D. (2012). Midlife fitness and the development of chronic conditions in later life. Archives of Internal Medicine, Aug 27, 1-8. doi: 10.1001/archinternmed.2012.3400.
• Bild, D.E. Thriving of the fittest: Comment on "Fitness and the development of chronic conditions in later life." (2012). Archives of Internal Medicine, Aug 27, 1-8. doi: 10.1001/archinternmed.2012.3400.
• The Lifestyle Interventions and Independence for Elders (LIFE) Study

September 2012