A systematic review has concluded that the current evidence seems to show improved outcomes in rheumatoid arthritis (RA) patients with obesity one year after bariatric and metabolic surgery (BMS) and surgery seems a promising alternative in reducing RA disease activity as well as morbidity and mortality, according to researchers from University Tunis El Manar, Tunis, Tunisia.
Higher levels of adiposity have been associated with higher risk of developing RA, and RA patients suffering from obesity are not only less likely to achieve remission or low disease activity, but adipocytokines produced by the adipose tissue maintain an inflammatory state in the synoviocytes which makes it difficult to achieve remission. Therefore, the authors noted that there is “a need for more stringent interventions to reduce weight in this population.”
Subsequently, the researchers hypothesised that weight loss is associated with a reduction of adipokine levels which would improve outcomes in RA and they conducted a systematic review to examine the evidence regarding the effect of BMS on outcomes of RA including disease activity as well as RA morbidity and mortality.
The systematic review identified three papers that met criteria: 1) Patients who underwent a BMS 2) Patients followed for RA with available data on disease outcomes before and after BMS. 3) Comparison of RA outcomes before and after surgery with or without a control group. 4) Cohort studies assessing RA outcomes over time. In total, 33193 patients and the mean age was 52.1 years. The mean number of RA patient who underwent BS was 6,700 and the mean disease duration of RA before BS was nine years. The mean BMI at baseline and after BS was 43.1kg/m2 and 29.7kg/m2, respectively.
Compared to non-surgical patients, weight loss after BMS was associated with lower disease activity. At 12 months post-surgery, 68% of subjects were in remission compared to 26% at baseline (p<0.001). Assessing the disease state using American College of Rheumatology RA classification criteria, they noted ACR20, 50 and 70 response rate were observed in 75.0%, 53.1% and 31.3% in the BMS compared to 51.5%, 39.4%, 21.2% in the non-surgery group (p<0.01, p<0.01, p<0.01) respectively. Regarding acute phase reactants, CRP and ESR were significantly lower at 12 months post-surgery (5.9 mg/L (SD 8.2), 26.1 mm/hr (SD 2.0)) compared to baseline (26.1 mg/L (SD 20.9), 45.7 mm/hr (SD 26.2)), (p<0.05, p<0.001), respectively.
The researchers also noted a significant reduction in the use of NSAIDs, Leflunomide, biologics and combination treatment in both surgery and non-surgery groups at 12 months, compared to baseline (p<0.01). This reduction did not concern corticosteroids, Methotrexate and Sulfasalazine use. Similarly, medication tapering in the bariatric group was not superior to that in non-surgical patients (p>0.05). One study showed that prior BMS in RA patients was significantly and independently associated with reduced odds ratios for all the morbidities, compared with no prior BMS (p<0.001).
“The two take-home messages derived from this systematic review are the following: i) Weight loss from BMS was associated with an improvement in disease activity outcomes in RA patients compared with no intervention. ii) RA patients with prior BMS were less likely to develop major morbidities and have a decreased in-hospital mortality compared to RA patients with obesity,” they authors noted.
As far as the authors are aware, this is the first systematic review to investigate the effect of BS on different aspects of RA including not only disease activity but also morbidity and mortality. However, they noted that bariatric procedures have been associated reduced bone mineral density in some studies, therefore any future studies should examine these particular issues.
The findings were featured in the paper, ‘Effect of bariatric and metabolic surgery on rheumatoid arthritis outcomes: A systematic review’, published in PlosOne. To access this paper, please click here