Meta-analysis of the effect of bariatric surgery on physical function

Background: Obesity leads to an impairment of physical function that limits the ability to perform basic physical activities affecting quality of life. Literature on the effect of bariatric surgery on physical function is confounding and generally of low quality. Methods: A comprehensive search was undertaken using MEDLINE, Scopus (including Embase), CENTRAL, PubMed, SPORTDiscus, Scirus and OpenGrey for published research and non-published studies to 31 March 2017. Studies employing objective measurement and self-reporting of physical function before and after bariatric surgery were included. The magnitude of experimental effect was calculated in terms of the standardized mean difference (MD), and confidence intervals were set at 95 per cent to reflect a significance level of 0 center dot 05. Results: Thirty studies including 1779 patients met the inclusion criteria. Physical function improved after bariatric surgery at 0-6 months (MD 0 center dot 90, 95 per cent c. i. 0 center dot 60 to 1 center dot 21; P < 0 center dot 001), more than 6 to 12months (MD 1 center dot 06, 0 center dot 76 to 1 center dot 35; P < 0 center dot 001) and more than 12 to 36months (MD 1 center dot 30, 1 center dot 07 to 1 center dot 52; P < 0 center dot 001). Objective assessment of physical function after bariatric surgery showed improvement at 0-6months (MD 0 center dot 94, 0 center dot 57 to 1 center dot 32; P < 0 center dot 001), more than 6 to 12months (MD 0 center dot 77, 0 center dot 15 to 1 center dot 40; P = 0 center dot 02) and more than 12 to 36months (MD 1 center dot 04, 0 center dot 40 to 1 center dot 68; P = 0 center dot 001). Self-reported assessment of physical function showed similar improvements at 0-6 months (MD 0 center dot 80, 0 center dot 12 to 1 center dot 47; P = 0 center dot 02), more than 6 to 12months (MD 1 center dot 42, 1 center dot 23 to 1 center dot 60; P < 0 center dot 001) and more than 12 to 36months (MD 1 center dot 41, 1 center dot 20 to 1 center dot 61; P < 0 center dot 001) after a bariatric procedure. Conclusion: Bariatric surgery improves physical function significantly within 6 months of the procedure and this effect persists over time to 36months after surgery, whether measured objectively or by self-reporting.