Higher Body Mass Index (BMI) is not linked to increased risk of death or other complications following shoulder replacement surgery, according to a new study by University of Oxford researchers.
Joint replacement surgeries – including hip, knee and shoulder replacements – can significantly improve quality of life. Many patients with obesity are denied these procedures despite a lack of formal recommendations from national organisations. Evidence on the risks of joint replacement surgery in patients with obesity is limited and mixed.
In this study, supported by the NIHR Oxford Biomedical Research Centre, researchers analysed more than 20,000 elective shoulder replacement surgeries performed across the UK and Denmark to see whether BMI was associated with death or other complications.
Compared to patients with a healthy BMI (21.75 kg/m2), patients with obesity (BMI 40 kg/m2) had a 60% lower risk of death within the year following surgery. Those considered underweight however, (BMI <18.5 kg/m2)had an 18% higher risk of death, in addition to an increased risk of other poor outcomes. The study does not support restricting patients with a high BMI from having elective shoulder replacement surgery, contrary to evidence that some hospitals are starting to restrict patients.
One limitation of this study was the small sample size of the underweight population (131 for the UK data and 70 for Danish data). However, this was a large study that consistently showed a lower risk of death in patients with obesity undergoing shoulder replacement surgery across multiple outcomes and two countries. The results can help patients, surgeons and policymakers make informed decisions about who should be considered fit for these surgeries.
Lead author Epaminondas Markos Valsamis from the Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS) says: “Shoulder replacements offer patients the opportunity for excellent pain relief and improved quality of life. Our research shows that patients with a higher BMI do not have poorer outcomes after shoulder replacement surgery.”
Senior author Professor Jonathan Rees adds: “While BMI thresholds have been used to limit access to joint replacement surgery, our findings do not support restricting higher BMI patients from accessing shoulder replacement surgery.”
This research was supported by the NIHR Oxford Biomedical Research Centre (BRC) and Aarhus University.
Read the paper, published in PLOS Medicine.
[RP1] The association of body mass index with patient outcomes after shoulder replacement surgery: Population-based cohort study using linked national data from the United Kingdom and Denmark | PLOS Medicine