Rates of secondary hyperparathyroidism after bypass operation for super-morbid obesity: An overlooked phenomenon

Evaluation of Long-Term Nutrition Outcomes After Duodenal Switch: A Systematic Review and Meta-Analysis

BACKGROUND

Biliopancreatic diversion with duodenal switch (BPD-DS) is the most effective and durable metabolic and bariatric surgery to achieve a target weight loss. However, many surgeons are hesitant to adopt BPD-DS due to a lack of training, technical complexity, and long-term nutrition deficiencies. This meta-analysis aimed to investigate long-term nutrition outcomes after primary BPD-DS in the management of obesity.

METHODS

Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to February 2023 by 2 independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) system. The review was registered prospectively with PROSPERO (CRD42023391316).

RESULTS

From 834 studies screened, 8 studies met the eligibility criteria, with a total of 3443 patients with obesity undergoing primary BPD-DS. At long-term follow-up (≥5 years), 25.4% of patients had vitamin A deficiency (95% CI: -.012, .520, I2 = 94%), and 57.3% had vitamin D deficiency (95% CI: .059, 1.086, I2 = 86%). Calcium deficiency was observed in 125 patients (22.2%, 95% CI: .061, .383, I2 = 97%), and 69.7% had an abnormal parathyroid hormone level (95% CI: .548, .847, I2 = 78%). Ferritin level was abnormal in 30 patients (29.0%, 95% CI: .099, .481, I2 = 79%).

CONCLUSIONS

Despite displaying comparable nutrition-related outcomes to mid-term follow-up, our study demonstrated that BPD-DS could result in a high level of long-term nutrition deficiency after BPD-DS for selected patients. However, further randomized controlled studies with standardized supplementation regimens and improvement in compliance are necessary to evaluate and prevent long-term nutritional deficiencies after BPD-DS.

Bariatric surgery and secondary hyperparathyroidism: a meta-analysis

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.

Prevalence and associated factors of secondary hyperparathyroidism after Roux-en-Y gastric bypass: A meta-analysis

This study aimed to investigate the prevalence and factors associated with secondary hyperparathyroidism (SHPT) after Roux-en-Y gastric bypass (RYGB). We searched PubMed, EMBASE, and CENTRAL for relevant studies using search terms gastric bypass, RYGB and hyperparathyroidism. Thirty-four cohort studies with 4331 patients were incorporated into the final meta-analysis. Overall estimates of the prevalence of SHPT following RYGB were 39%. Subgroup analyses indicated the pooled prevalences of SHPT were 25%, 42%, 48%, and 54% for ≤1 year, >1 and ≤5 years, >5 and ≤10 years, and >10 years, respectively, after RYGB. Meta-regression showed that SHPT occurred was positively related to follow-up durations (p = 0.001). Additionally, SHPT prevalence was higher in studies in which calcium and vitamin D supplementation were considered inadequate than in those which were adequate (p = 0.002). SHPT is highly prevalent in individuals with obesity after RYGB. It seems to progress with time after surgery. Routine calcium and vitamin D supplementation post-RYGB together with targeted treatment of vitamin D deficiency, reasonable adjustment of the doses of supplementation with regular follow-up, and improved patient compliance, as well as long-term screening, are necessary to prevent the development of SHPT.

Hospital Readmissions for Hyperparathyroidism After Bariatric Surgery in the United States: A National Database Review

Introduction: The incidence and significance of hyperparathyroidism in patients after bariatric surgery have been established to some degree; however, the impact it has on the national healthcare system has not. We sought to assess the risk of readmission and related comorbidities in this patient population.

Methods: The Healthcare Cost and Utilization Project Nationwide Readmission Database was queried for all patients who underwent Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Multivariate logistic regression analysis was conducted to identify factors associated with readmission for hyperparathyroidism.

Results: A total of 915,792 patients between 2010 and 2015 were queried; 43.2% had undergone SG and 56.8% had RYGB. A total of 589 patients were readmitted for hyperparathyroidism; 80.8% were female and 68% had a Charlson comorbidity index ≥ 2. Factors associated with readmission were as follows: age 45-64 years (odds ratio [OR] 1.42, p=0.001), Medicare (OR 3.01, p<0.001) or Medicaid (OR 2.61, p<0.001) insurance status, lower median household income, renal failure (OR 17.14, p<0.001), hypertension (OR 2.89, p<0.001), and deficiency anemia (OR 2.62, p<0.01).

Conclusions: Parathyroid axis monitoring may provide benefits to predictably high-risk patients. Appropriate surveillance may decrease the impact of bariatric hyperparathyroidism readmission on the U.S. healthcare system.

Recommendations Based on Evidence by the Andalusian Group for Nutrition Reflection and Investigation (GARIN) for the Pre- and Postoperative Management of Patients Undergoing Obesity Surgery

In order to develop evidence-based recommendations and expert consensus for nutrition management of patients undergoing bariatric surgery and postoperative follow-up, we conducted a systematic literature search using PRISMA methodology plus critical appraisal following the SIGN and AGREE-II procedures. The results were discussed among all members of the GARIN group, and all members answered a Likert scale questionnaire to assess the degree of support for every recommendation. Patients undergoing bariatric surgery should be screened preoperatively for some micronutrient deficiencies and treated accordingly. A VLCD (Very Low-Calorie Diet) should be used for 4–8 weeks prior to surgery. Postoperatively, a liquid diet should be maintained for a month, followed by a semi-solid diet also for one month. Protein requirements (1–1.5 g/kg) should be estimated using adjusted weight. Systematic use of specific multivitamin supplements is encouraged. Calcium citrate and vitamin D supplements should be used at higher doses than are currently recommended. The use of proton-pump inhibitors should be individualised, and vitamin B12 and iron should be supplemented in case of deficit. All patients, especially pregnant women, teenagers, and elderly patients require a multidisciplinary approach and specialised follow-up. These recommendations and suggestions regarding nutrition management when undergoing bariatric surgery and postoperative follow-up have direct clinical applicability.

Impact of bariatric surgery on bone tissue

The important prevalence and morbidity of obesity has generated an increase in bariatric surgery. It has a positive effect in obesity-related comorbidities. However, it's detrimental to bone health. The underline pathophysiological mechanisms are complex and heterogeneous. The knowledge of these factors may lead us to develop an adequate therapeutic intervention.

Vitamin D Metabolism in Bariatric Surgery

Hypovitaminosis D is common in obese patients and persists after roux-en-Y gastric bypass and sleeve gastrectomy. Several societies recommend screening for vitamin D deficiency before bariatric surgery, and replacement doses of 3000 IU/d and up to 50,000 IU 1 to 3 times per week, in case of deficiency, with periodic monitoring. These regimens are mostly based on expert opinion. Large trials are needed to assess the vitamin D dose response, by type of bariatric surgery, and evaluate the effect on surrogate markers of skeletal outcomes. Such data are essential to derive desirable vitamin D levels in this population.