Weight Loss with the Incorporation of Meal Replacements may Trim Down Arthritis Pain Among Older Obese Adults

10/08/06 Losing weight with an intervention of a reduced-calorie diet that incorporates Slim-Fast meal replacements and exercise training along with education and lifestyle behavior changes can significantly reduce the pain and physical impairment of osteoarthritis (OA) in obese people age 60 or older, according to a study published in the July issue of Obesity, the official journal of the North American Association for the Study of Obesity (NAASO).

Osteoarthritis, a degenerative joint disease, occurs when the cartilage that covers the ends of bones in the joint deteriorates. The condition affects more than 20 million Americans, particularly people over age 65, and causes great pain and difficulty moving as the bones rub against one another. Osteoarthritis is the leading cause of disability in the United States, and being overweight is a risk factor in the development and progression of arthritis. In fact, researchers have shown that the percentages of arthritis cases linked directly to obesity (body mass index, or BMI, greater than or equal to 30) has risen from 3% in 1971 to 18% in 2002, with obese people in 2002 60 percent more likely to develop arthritis than those who aren't overweight.

"The good news is that it's never too late--weight loss along with a regular exercise program can improve physical function-even as we age. "Both obesity and arthritis affect mobility" said Patricia Groziak, MS, RD, Senior Manager, Medical Marketing for Slim-Fast. "The results of this study show that older obese adults can safely and successfully lose weight while improving their ability to walk, climb stairs, lift groceries and perform other daily activities."

The study included 87 people ages 60 or older with a BMI greater than or equal to 30 (roughly equal to about 30 extra pounds in a five-foot, four-inch tall person) who had been diagnosed with OA of the knee and reported difficulty with physical activities. The participants were randomly assigned to either an "Intensive Weight Loss" or a "Weight Stable Control" program.

The weight loss program included a balanced, reduced-calorie diet (energy deficit of 1,000 calories per day based on individual estimated needs) with exercise three days a week. The diet included up to two Slim-Fast meal replacements (bars and shakes) each day. The target weight loss was 10 percent within six months.

After six months, the average weight loss was 8.7 percent among people in the weight loss program; nearly half of the people had a weight loss of at least 10 percent. Weight loss was safe and compliance to the meal replacement was good; no adverse events were attributed to the weight loss program in this study. By comparison, few people (less than 10 percent) in the weight stable group lost at least 5 percent of their body weight.

This weight loss strategy improved self-reported function and pain by 33 percent and physical performance by 15 percent, with significant reductions in body fat. People who lost the most weight also had the most improved physical functioning, suggesting that greater weight loss may lead to better outcomes. Results of this study do not support the notion that weight loss in the elderly produces excessive decreases in fat-free mass and a resulting acceleration in functional decline.

This is the first randomized control trial that looked at changes in physical function and body composition following an intensive weight loss intervention exclusively in older adults. One-quarter of American adults are considered obese (body mass index, or BMI), and are four times more likely to develop knee OA than people who are not overweight or obese (BMI less than or equal to 25).