Weight loss lessens symptoms of arthritis in former NFL athletes

Issue: April 2011

SAN DIEGO – Isolated weight loss results in a significant reduction of arthritis symptoms in obese patients, according to a study presented here.

Christopher Edwards, shared his findings at the 2011 American Orthopaedic Society for Sports Medicine Specialty Day Meeting.

Obesity is prevalent among former NFL players, and Edwards said his group hypothesized this obesity was at least partially to blame for the increased risk of knee osteoarthritis (OA) in the former player population.

Higher BMIs

“Notably, men under the age of 60 who played in the NFL are three times more likely to develop knee osteoarthritis than the general population,” Edwards said. “No one has accounted for this. It may be related to their higher BMI.”

“Individuals with a BMI greater than 30 have a four times greater risk of developing knee OA than those with a BMI of less than 25,” he added.

The study’s goal was to investigate isolated weight loss as a treatment for the symptoms of knee OA in a cohort of obese patients with radiographically confirmed arthritis.

Bariatric surgery patients

Edwards said his study investigated 24 adult patients scheduled to undergo bariatric surgery. The patients all exhibited clinical and radiographic evidence of knee OA. The WOMAC and KOOS surveys were administered preoperatively, and then at 6 and 12 months postoperatively. Each patient’s weight was recorded at baseline and at each follow-up appointment.

Changes from baseline were analyzed statistically through univariate analysis with the Student’s T test and Sign Rank test.

Edwards noted the patients were not prescribed exercise programs, medications, or injections during the study.

Weight loss at 6 and 12 months postoperatively was reported to be statistically significant. Edwards added that all variables from both the KOOS and WOMAC surveys at the postoperative follow-ups were shown to have improved to a statistically significant degree relative to the baseline measurements.

Each individual, Edwards reported, showed some kind of improvement in their pain as a result of losing weight.

“We have shown in this particular patient population that pain, stiffness and physical function can be significantly improved with isolated weight loss,” he said.

He added that though such uses were not examined in the study, there could be potential for an expanded role of weight loss in the treatment of knee arthritis in older and retired athletes. – by Robert Press

Reference:

Edwards C, et al. Isolated weight loss significantly reduces the symptoms associated with knee arthritis. Paper 9508. Presented at the 2011 American Orthopaedic Society for Sports Medicine Specialty Day. Feb. 19. San Diego.

Christopher Edwards, is a student at the Penn State University School of Medicine. He can be reached at cedwards@hmc.psu.edu.

Disclosure: Edwards has no relevant financial disclosures.

I thought it was a great study. There have been a few studies that have correlated BMI with the degree of OA and/or subjective complaints of knee pain in general. There have been some attempts at biochemical analysis in orthopedic literature to say that certain biochemical factors may be present to a higher degree in the obese patients – biochemical correlations in the osteoarthritic knee with the degree of obesity. That is probably not a chicken and egg concept: More arthritis, more symptoms, therefore more presence of biochemical factors.

The intuitive argument is: When a patient comes in the office and says their knee hurts, but they are sitting on the examination table and have no pain, then they jump off the table and have a little pain, then they walk and have a little more pain, then they go up and down stairs and have a little more pain … in my opinion, a significant component of pain coming from OA is load-related. When a patient is symptomatic with osteoarthritis, load is often what bothers them. It does not mean it will necessarily progress; it is just that they feel more pain with more load. One could argue the same phenomenon occurs when a patient says, “I can do everything except run. When I run, I have pain.” That is just a function of load.

However, to draw a direct correlation between obesity and OA in this study – I do not think you can do that. You can draw the conclusion that knees hurt with more load, or at least start thinking about it in that way. You have to separate out activity level, which could increase with weight loss. That is another interesting way you can look at this.

— Brian J. Cole, MD, MBA
Rush Cartilage Restoration Center
Rush University Medical Center, Chicago, IL
Disclosure: He is a consultant to Arthrex and Genzyme.