Obesity Abstracts

Obesity is an important modifiable risk factor for developing osteoarthritis. Arthroplasty improves mobility and quality of life in those with osteoarthritis. BMI thresholds are mandated by some commissioning bodies in the UK, leading to extended waiting times for arthroplasty. Obesity is associated with increased complications after arthroplasty. It is unknown if these risks can be mitigated by weight loss pre-operatively. Our systematic review and meta-analysis explores the association between weight loss pre-arthroplasty and peri- and post-operative outcomes.

Methods: Our review was registered with PROSPERO. We searched keywords on Pubmed, EMBASE, Ovid, Web of Science, Google Scholar, Europe PMC and throughout grey literature. Studies included those who underwent either medical and/or surgical weight loss prior to arthroplasty. Exclusion criteria included: articles pre-2010, case studies, those assessing outcomes in upper limb arthroplasty, revision surgery and articles not published in English. Outcome measures included incidence of superficial wound infection, deep wound infection, pulmonary embolus, deep vein thrombosis (DVT) and revision surgery up to 90 days post-arthroplasty. The intervention group included patients living with obesity who lost weight pre-arthroplasty. The control group were patients of any BMI who underwent arthroplasty without intervention.

Results: 21 articles were included, with data available for 50,672 patients in the intervention group and 1,446,755 patients in the control group. Pre-arthroplasty weight loss was associated with an increased risk of revision surgery (Odds Ratio (OR) 1.32, 95% CI [1.13,1.53], P=0.0004) and DVT (OR 1.37, 95% CI [1.23 to 1.52], P0.00001). However, there was no association between pre-arthroplasty weight loss and superficial wound infection (OR 1.08, 95% CI [0.84 to 1.40], P0.54), deep wound infection (OR 0.97, 95% CI [0.77 to 1.22], P0.79) or pulmonary embolism (OR 0.93, 95% CI [0.78 to 1.10], P0.38).

Conclusion: These data suggest that weight loss prior to arthroplasty does not reduce the risk of perioperative complications and may increase the risk of DVT and revision surgery. However, well-designed and adequately powered prospective studies are required to establish the risks and benefits of pre-arthroplasty weight loss in people living with obesity. Further research into the causative link between obesity and operative complications is also required.