ST. LOUIS, Mo. – Obesity aggravates the typical age-related decline in physical function and increases frailty, but much about this progression appears to be reversible. Dennis T. Villareal, MD, of Washington University School of Medicine in St. Louis, tested a diet and exercise intervention in a controlled trial in frail obese older volunteers. He reports that the treatment group lost weight, improved physical function, gained strength, and was generally better able to manage the activities of daily living.

Dr. Villareal's study also showed that strength-building exercise does not accelerate the usual age-related loss of fat-free mass that leads to sarcopenia in such patients.

The new study, published in the April 24, 2006, issue of the Archives of Internal Medicine,¹ is the first randomized, controlled trial to evaluate the effects of weight loss and exercise on frail obese older adults. Currently, about 20.3% of American adults aged 65 and older are obese, according to statistics cited in the new study.

After screening 40 obese older volunteers, Dr. Villareal and colleagues randomized 27 frail obese patients to either 6 months of weekly behavioral therapy for weight loss with 90-minute exercise training sessions three times a week, or a no-treatment/usual care control group. Study participants had an mean age of 70 and an average body mass index of 39. The treatment group program comprised a diet that reduced caloric intake by 750 calories per day and study exercise sessions focusing on flexibility, endurance, strength, and balance.

Patients lose fat, gain strength

Patients in the treatment group lost an average of 8.4% of body weight. In contrast, weight did not change among those participants in the control group. Moreover, fat mass decreased by a mean of 6.6 kg in the intervention groups compared with a mean of 1.7 kg in the control group. Participants in the treatment group also improved by about 2.6 points on the Physical Performance test, which is used to assess physical function. Control group participants improved by 0.1 points on this standardized measure, the study showed. Participants in the intervention group also showed improvements in strength, walking speed, obstacle course, 1-leg limb stance time, and certain quality-of-life measures.

"These findings demonstrate that weight loss and regular exercise have important beneficial effects in frail obese older adults by improving functional status and health-related quality of life," Dr. Villareal said. "If frailty is related to obesity, it can be reversed, and this is encouraging."

Motivation may be key to compliance

While not an issue in the new study, compliance may be an issue outside of this research setting, the researchers note. During the trial, two subjects in the treatment group did not comply, and one patient in the control group dropped out of the study.

"It has been suggested that successful weight loss is difficult to achieve in the older population because of ingrained lifelong diet and activity habits, and attempts to change these habits will cause distress and anxiety," the investigators write. However, they point out, most subjects looked forward to the weekly group meetings and regular exercise sessions and "embraced lifestyle changes." Yet because study subjects did volunteer to be part of the research project, these results may not be generalizable, they point out. Dr. Villareal and colleagues are continuing the study to determine if compliance can be maintained after 6 months.

"We don't know if people will be as compliant outside of the study," Dr. Villareal said. "We know that older patients are interested in maintaining physical function and their independence in the community, so if they can follow this intervention, they will lose weight and derive substantial benefits, which may give them the proper motivation."

"I was struck by the amount of weight loss that these people had," said Stephen Honig, MD, director of the osteoporosis center at New York University Hospital for Joint Diseases in New York City. "Clearly, the combination of behavioral changes and exercise can work to [help people] lose weight, and that in and of itself is a plus," he told CIAOMed. "Changes in some of the standard objective measures of physiological function [seen in the study] all speak to the fact that there was improvement based on weight reduction alone," he says.
 
Although the new study does not provide many clues for how to treat frailty in the thin osteoporotic female patient that Dr. Honig typically sees, he said, "It does show that no matter how old you are, if you are overweight, weight reduction can have a positive physiologic result as well as a positive effect on muscles."

Reference

1. Villareal DT, Banks M, Sinacore DR, Siener C, Klein S. Effect of weight loss and exercise on frailty in obese older adults. Arch Intern Med. 2006;166:860-866.