Pain, physical function improves after bariatric surgery for severe obesity

A large proportion of patients with severe obesity who underwent either Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding experienced improvements in pain, physical function and walk time during the first 3 years after surgery, according to data published in JAMA.

“Although evidence of improvements in pain and physical function following bariatric surgery is increasing, the variability and durability of improvement have not been well described — with most studies limited by small sample size and follow-up of 1 year or less by the study of obsolete surgical procedures,” Wendy C. King, PhD, of University of Pittsburgh, and colleagues wrote.

To assess changes in pain and physical function over 3 years after bariatric surgery, and to identify factors linked to improvement, King and colleagues conducted the Longitudinal Assessment of Bariatric Surgery-2 study. This was an observational cohort study evaluating 2,458 adults who underwent bariatric surgery between March 2006 and April 2009 at 10 U.S. hospitals.

Patients were evaluated before surgery and annually for 3 years after surgery, with clinically meaningful improvements in bodily pain, physical function and walk time serving as the primary endpoints. Improvement in the Western Ontario McMaster Osteoarthritis Index served as the key secondary endpoint.

Of the 2,221 patients who completed baseline and follow-up evaluations, 78.5% were women, median age was 47 years (range, 37–55 years), median BMI was 45.9, 70.4% underwent Roux-en-Y gastric bypass, 25% underwent laparoscopic adjustable gastric banding, and less than 5% underwent another procedure.

At 1 year, 57.6% (95% CI, 55.3-59.9) experienced improvements in pain, 76.5% (95% CI, 74.6-78.5) experienced improvements in physical function and 59.5% (95% CI, 56.4-62.7) experienced improvements in walk time. Of the 633 patients with baseline severe knee pain or disability, 77.1% (95% CI, 73.5-80.7) experienced joint-specific improvements, and of the 500 patients with baseline severe hip pain or disability, 79.2% (95% CI, 75.3-83.1) experienced improvements. Most patients with a mobility deficit at baseline experienced remission at year 1 (55.6%; 95% CI, 52-59.3).

Between years 1 and 3, improvement rates for pain dropped to 48.6% (95% CI, 46-51.1) and improvement rates for physical function dropped to 70.2% (95% CI, 67.8-72.5), whereas improvement rates for walk time, knee pain and function, and hip pain and function did not decrease (all P .05)

Factors associated with improvements included younger age, male sex, higher income, lower BMI, fewer depressive symptoms before surgery, no diabetes and no venous edema with ulcerations after surgery, and presurgery-to-postsurgery reductions in weight and depressive symptoms.

“The findings from this study reinforce shorter-term results from studies that have reported significant improvements in SF-36 bodily pain and physical function scores, WOMAC scores, walking capacity … resting heart rate, or other measures of pain and function in the first 3 to 12 months following RYGB or LAGB,” the researchers concluded. – by Adam Leitenberger