Bariatric surgery and secondary hyperparathyroidism: a meta-analysis

Abstract

Background: Obesity increases the risk of obesity-related medical problems. Weight loss after metabolic and bariatric surgery (MBS) has been well studied. However, the effects of MBS on parathyroid function remain unclear.

Objective: The objective of this study was to perform a meta-analysis to examine the impact of MBS on the risk of secondary hyperparathyroidism (SHPT).

Setting: The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.

Methods: The PubMed, Embase, Web of Science, and the Cochrane Library databases were systematically reviewed from inception to May 2022 to identify studies reporting quantitative measurements of SHPT risk pre-MBS and post-MBS. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated and compared. Effects were pooled using a random-effects or fixed-effects model. Subgroup analyses were performed according to the follow-up time and surgical procedure.

Results: The final meta-analysis included 9 studies with a total of 5585 patients. The mean follow-up time was 3.5 years (range 0.25-5). Overall, MBS appears to does not affect SHPT risk (OR = 1.34, 95% CI 0.81-2.20, I² = 95%). Follow-up data showed no evidence of SHPT within 2 years following gastric bypass (GB) and sleeve gastrectomy procedures (OR = 1.42, 95% CI 0.66-3.07 for GB, OR = 0.39, 95% CI 0.09-1.62 for sleeve gastrectomy ). At the 2-year and long-term follow-up intervals, a marked increase in SHPT was detected for GB (OR = 6.06, 95% CI 3.39-10.85 for GB). In addition, the surgical procedure for GB decreased the likelihood of SHPT compared with the surgical procedure for biliopancreatic diversion with duodenal switch (OR = 0.29, 95% CI 0.17-0.49).

Conclusions: Our meta-analysis indicated that GB appears to increase SHPT risk. Patients undergoing MBS should be aware of the risk of SHPT. Larger studies are needed to evaluate the outcomes and side effects and may eventually provide a better and more comprehensive understanding of the risks.

Keywords: Bariatric surgery; Hyperparathyroidism; Meta-analysis.