Dr Furkan Genel1,4, Dr Michael Kale2, Natalie Pavlovic1,4, Prof Vicki Flood3, A/Prof Justine Naylor1,4, A/Prof Sam Adie1
1Faculty of Medicine, University Of New South Wales, 2Faculty of Health and Medicine, University of Newcastle, 3Faculty of Medicine and Health, University of Sydney, 4Whitlam Orthopaedic Research Centre, Ingham Institute for Applied Medical Research
The aim is to systematically assess the health impact of a low-inflammatory diet intervention (full-diet or supplement), compared to usual diet or other dietary interventions, on weight change, inflammatory biomarkers, joint symptoms, and quality-of-life in adults with osteoarthritis, rheumatoid arthritis or seronegative arthropathy (psoriatic, reactive, ankylosing spondylitis or IBD-related), on outcomes assessed in prospective studies within 6 months of intervention commencement (PROSPERO-CRD42019136567). Search of multiple electronic library databases from inception to July 2019, supplemented by grey literature searches, for randomised and prospective trials assessing the above objective. After exclusion of 446 ineligible studies, five randomised and two prospective trials involving 468 participants with either osteoarthritis or rheumatoid arthritis were included. GRADE assessment for all outcomes was very low. Meta-analyses produced the following standardised mean differences (SMD) and 95% confidence interval (CI) 2–4 months following commencement of the diets favouring the low-inflammatory diet: weight SMD −0.45 (CI −0.71, −0.18); inflammatory biomarkers SMD −2.33 (CI −3.82, −0.84). No significant effects were found for physical function (SMD −0.62; CI −1.39, 0.14), general health (SMD 0.89; CI −0.39, 2.16) and joint pain (SMD −0.98; CI −2.90, 0.93). In most studies, the quality of dietary intervention (dietitian input, use of validated dietary compliance tool) could not be gauged. In conclusion, very low-level evidence suggests that low-inflammatory diets or supplements compared to usual diets are associated with greater weight loss and improvement in inflammatory biomarkers. More high-quality trials are needed to assess the health effects of a low-inflammatory diet more comprehensively and conclusively in arthritic conditions.
Dr Furkan Genel (B Med Sci (Hons), MD) is currently completing his PhD at UNSW. He worked was an Orthopaedic Registrar in Christchurch Hospital, New Zealand. Furkan’s research focuses on addressing issues affecting complications after knee or hip arthroplasty.