Fitness in middle age reduces risk of developing chronic diseases
According to a new study, physical fitness in middle age significantly reduces the risk of developing chronic diseases in later life. Researchers affiliated from the Cooper Institute at the University of Texas Southwestern Medical Center in Dallas published their findings online on August 27 in the Archives of Internal Medicine.
The researchers noted that the association between cardiorespiratory fitness and mortality has been well documented in the medical literature; however, the association between midlife fitness and the development of nonfatal chronic conditions in older age has not been studied.
Therefore, they designed as study to examine the association between midlife fitness and chronic disease outcomes in later life. Data from the Cooper Center Longitudinal Study were linked with Medicare claims. They reviewed 18,670 healthy individuals (21.1%: women; average age: 49 years) who survived to receive Medicare coverage from January 1, 1999 through December 31, 2009. Fitness estimated by Balke treadmill time was analyzed as a continuous variable (in metabolic equivalents (METs)) and according to age- and gender-specific factors. The investigators defined eight common chronic conditions; associations between these chronic conditions and midlife fitness were assessed. The conditions were adjusted for age, body mass index, blood pressure, cholesterol levels, glucose levels, alcohol use, and smoking.
The researchers found that after 120,780 person-years of Medicare exposure with a median follow-up of 26 years, the highest quintile of fitness (quintile 5) was associated with a lower incidence of chronic conditions compared with the lowest quintile (quintile 1) in men (15.6 vs. 28.2 per 100 person-years) and women (11.4 vs. 20.1 per 100 person-years). A higher fitness (in METs) was associated with a lower risk of developing chronic conditions in both men and women. Among individuals who expired (2,406; 12.9%), higher fitness was associated with a lower risk of developing chronic conditions relative to survival.
The researchers concluded that in this group of healthy middle-aged adults, fitness was significantly associated with a lower risk of developing chronic disease outcomes during 26 years of follow-up. The investigators noted that their findings indicate that a higher level of midlife fitness was associated with a delay in the development of chronic conditions; therefore, morbidity is delayed until nearer the end of life in fitter individuals.
In a related editorial, Diane E. Bild, MD, MPH, from the Division of Cardiovascular Sciences at the National Heart, Lung, and Blood Institute, in Bethesda, Maryland, noted that the study provides “further evidence for physical fitness as a contributor to healthy aging and the compression of morbidity.” She added that in addition to this observational study, the ongoing Lifestyle Interventions and Independence for Elders trial will compare a moderate-intensity physical activity program with a successful aging health education program in 1,600 sedentary older persons who will be monitored for an average of 2.7 years.
Reference: Archives of Internal medicine