According to a study by researchers at Wake Forest University in Winston-Salem, North Carolina, intensive diet and exercise can dramatically reduce the amount of pain in older adults with osteoarthritis of the knee and improve function and gait speed .The study Intensive Diet and Exercise on Arthritis (IDEA, for its acronym in English) of 18 months was intended to assess the impact of intense weight loss with or without exercise in the progression of the disease. The results presented here at the 2011 Annual Meeting of the American College of Rheumatology is the first study and focus only on pain and function.
The researchers randomly distributed to 454 individuals with pre-obesity and obesity (72% women) with a mean body mass index of 33.6 kg / m 2 and an average age of 65.6 years, one of three groups: intensive diet designed to achieve a weight loss of 10% or more, only moderate exercise (two marches of 15 minutes and 20 minutes of exercise to reduce weight three times a week), or both. Participants were served each week during the first six months and every two weeks thereafter. Eighty-eight percent of participants reached the final 18 months study.
At study end, participants in the diet-only group had an average loss of 9.5% of their initial weight and group exercise conducted only reached an average loss of 2.2%.However, diet and exercise group had a combined average of 11.4% loss. None of the participants returned to the initial figures, even after 18 months.
While all groups reported less pain at six months, the difference between groups was not significant. However, at 18 months, the group combined with diet and exercise showed a 51% reduction in pain compared with 27% and 28% in the groups that received only diet and exercise only, respectively ( p <0, 0004), said lead author Dr. Stephen P. Messier, PhD, JB Snow Biomechanics Director of Laboratory at Wake Forest University . He said that 40% of patients in the combined group rated their pain at 0 or 1 to 18 s's, compared with 20% of groups with only exercise and diet alone.
In addition, participants in the group with diet / exercise improved their functional status 47%, compared with 30% in the diet-only group and 26% in the exercise only group. The combination group also increased walking speed by 12%, compared with 10% and 6% in the groups that received only diet or only exercise, respectively ( p = 0.004).
Dr. Messier said: "Surely our cohort has reversed the trend of decreasing mobility observed in older adults." In fact, the combination group had a faster walking speed than women in healthy middle-aged 40 to 62, and an equivalent of middle-aged healthy men.
Dr. Eric L. Matteson, chairman of the Department of Rheumatology at the Mayo Clinic in Rochester, Minnesota, said the most interesting finding of this study is that even patients who did not exercise had less pain.
He said: "Both exercise and diet are a formidable method to improve pain and function, but what was unique in this study was the observation that patients who lost weight had less pain associated with weight loss, even with some exercise. " This could be the result of a lower burden on the joints, he said, and could enable patients to postpone joint replacement operations.
It is also possible that patients can reduce the amount of analgesics taken if lose weight, noted Dr. Messier, something his group hopes to show by further analysis. He said: "We hope that from the standpoint of public health decreases medication use."
The key message, he said, is that "Doctors can tell patients that have a great improvement in pain and function in six months or so." The fact that no significant differences appeared between the groups until 18 months, however, "underscores the need for long-term studies to detect clinically and statistically significant results.
