Telomere length in patients with obesity submitted to bariatric surgery: A systematic review

Background Patients with obesity show evidence of increased levels of inflammation, oxidative stress and premature ageing. Telomere length (TL) is a key marker of cellular ageing, and patients with obesity often present shorter TL. Bariatric surgery (BS) is currently the most effective treatment for severe obesity. The aim of this systematic review was to explore whether the beneficial health effects observed after surgery in obese patients correspond to a restoration in TL or slower rates of shortening. As a secondary aim, we evaluated, at baseline and post‐surgery, the relationship between TL and different factors that could play a role in TL changes along time. Methods Searches for relevant articles were performed in MEDLINE, Web of Knowledge and SCOPUS. Prospective longitudinal studies that evaluated leukocyte TL in adult patients who had undergone BS were included. Data were extracted and evaluated by two independent researchers. The protocol was registered in PROSPERO with the number CRD42020197711. Results Seven studies based on independent samples that fulfilled our inclusion criteria were included. Obese patients showed shorter telomeres compared to healthy individuals. Long‐term studies (>2 years) seem to suggest an improvement in TL after surgery presumably due to the improvement of the inflammatory and oxidative levels of the patients induced by weight loss. Conclusion Studies seem to point towards a beneficial long‐term effect of BS on TL recovery. However, the scarce number of studies and the heterogeneity in the variables analysed in the different cohorts make it difficult to draw a firm conclusion. More studies are needed to evaluate long‐term changes to TL following BS. Highlights Severity of obesity may have a negative effect on telomere length (TL). Despite numerous beneficial effects of bariatric surgery, the recovery of TL seems to only be apparent at long‐term follow‐up.