Preventing calcium and vitamin D deficiencies following weight loss and metabolic surgery

Preoperative Micronutrient Repletion Strategies in Metabolic and Bariatric Surgery: A Systematic Review

BACKGROUND

Evidence is lacking to inform how micronutrient deficiencies should be prevented and treated before metabolic-bariatric surgery to optimize patient outcomes.

OBJECTIVE

This systematic review aimed to examine the effect of preoperative repletion strategies for micronutrient deficiencies on micronutrient biochemistry, quality of life, and complication rates among candidates for metabolic and bariatric surgery compared with usual care, alternate strategies, or no treatment.

METHODS

PubMed, Embase, CINAHL, and CENTRAL was searched in April 2024. A grey literature search was updated in April 2024 via Google search. Eligible observational and interventional studies were those that provided micronutrient repletion before the surgery and measured micronutrient status pre- and/or postsurgery. Studies with participants who were pregnant, lactating, or elected jejunocolic bypass, jejunoileal bypass, vertical banded gastroplasty, and biliopancreatic diversion were excluded. Risk of bias was assessed using the Academy of Nutrition and Dietetics Quality Criteria Checklist. Findings were narratively synthesized and the Grading of Recommendation, Assessment, Development and Evaluations was adopted when applicable. Twenty studies (n = 27 groups) were included (n = 15 observational; n = 5 interventional).

RESULTS

Strategies targeted vitamins A, D, E, B6, B12, C, thiamin, folate, calcium, iron, selenium, and zinc, including chronic dosing of oral supplements and multivitamins (n = 21), megadoses of oral supplements (n = 1), intramuscular injection (n = 1), intravenous infusion (n = 1), and a mix of injection and oral supplements (n = 3). Preoperative repletion strategies varied in efficacy. Chronic dosing of oral supplements increased vitamin D levels (n = 4 interventional studies; Grading of Recommendation, Assessment, Development and Evaluations rating: moderate). Multivitamins did not improve vitamin B12 status but improved status of vitamin B6, vitamin C, and folate. Iron infusion (n = 1) increased ferritin levels, despite small sample size and low adherence rate, whereas oral iron supplementation resulted in unchanged (n = 4) or decreased (n = 1) ferritin levels.

CONCLUSIONS

Proactive and personalized micronutrient repletion schedules may decrease the risk of preoperative and early postoperative deficiency.

LLL 44 - Module 3: Micronutrients in Chronic disease

Micronutrients (MN), i.e. trace elements and vitamins, are essential organic molecules, which are required in the diet in relatively small amounts in any form of nutrition (oral, enteral, parenteral). The probability of MN depletion or deficiencies should be considered in all chronic illnesses, especially in those that can interfere with intake, digestion, or intestinal absorption. Low socio-economic status and food deprivation are recognized as the most prevalent reasons for MN deficiencies world-wide. Elderly multimorbid patients with multimodal therapy, as well as patients with long-lasting menu restrictions, are at high risk for both disease related malnutrition as well as multiple MN deficiencies, needing careful specific follow-up. The importance of monitoring MN blood levels along with CRP is essential for optimal care. Drug interactions are also highlighted. In patients with chronic conditions depending on medical nutrition therapy, the provision of adequate dietary reference intakes (DRI) of MN doses and monitoring of their adequacy belongs to standard of care.

Visual Analysis of Nutrient Deficiency and Treatment Protocols in Bariatric Surgery Based on VOSviewer

Objective

To analyze the global literature on nutritional deficiencies in bariatric surgery (BS) since January 1, 1985, and to discuss the current status of research, research hotspots, and new development trend and treatment of nutritional deficiency in bariatric surgery. It provides ideas and basis for promoting the development of bariatric surgery and new alternative therapy or treatment protocols.

Methods

The Web of Science (WOS) database core collection was used as the data source, and VOSviewer 1.6.17 software was used to search the literature on the topic of “nutritional deficiencies in bariatric surgery.” The number of published literature, the distribution of authors, institutions, and countries, keyword cooccurrences, and journal cocitations were visualized and analyzed.

Results

A total of 1015 relevant publications was obtained after searching and screening, and the overall trend of literature published was on the rise. The most published countries, institutions, and authors were USA, University of Sao Paulo, Ramalho, Andrea; Obesity Surgery has been the most frequently cited journal (7943 citations), and the top 10 journals had high impact factors. Keyword cooccurrence analysis showed that “bariatric surgery” and “nutritional deficiencies” are the hot topics of research in this field.

Conclusion

There is an urgent need for bariatric surgery issuing institutions and authors to strengthen cross-institutional, cross-team, and multicenter and multidisciplinary cooperation, to promote and facilitate the exchange and cooperation in the field of bariatric surgery between developed countries in Europe and America and developing countries in Asia, Africa, and Latin America, to draw the attention of developing countries to the health problems caused by obesity, and to encourage and support the development of developing countries in this field. Bariatric surgery, obesity, weight loss, Y-type gastric bypass, gastric bypass, and nutritional deficiency are the hot research topics in the field of nutritional deficiency in bariatric surgery, and metabolic surgery, single anastomosis gastric bypass, micronutrient supplementation, micronutrient deficiency, intestinal microbiology, and guidelines are the new trends in this field.

Pre-Operative Assessment of Micronutrients, Amino Acids, Phospholipids and Oxidative Stress in Bariatric Surgery Candidates

Obesity has been linked to lower concentrations of fat-soluble micronutrients and higher concentrations of oxidative stress markers as well as an altered metabolism of branched chain amino acids and phospholipids. In the context of morbid obesity, the aim of this study was to investigate whether and to which extent plasma status of micronutrients, amino acids, phospholipids and oxidative stress differs between morbidly obese (n = 23) and non-obese patients (n = 13). In addition to plasma, malondialdehyde, retinol, cholesterol and triglycerides were assessed in visceral and subcutaneous adipose tissue in both groups. Plasma γ-tocopherol was significantly lower (p < 0.011) in the obese group while other fat-soluble micronutrients showed no statistically significant differences between both groups. Branched-chain amino acids (all p < 0.008) and lysine (p < 0.006) were significantly higher in morbidly obese patients compared to the control group. Malondialdehyde concentrations in both visceral (p < 0.016) and subcutaneous (p < 0.002) adipose tissue were significantly higher in the morbidly obese group while plasma markers of oxidative stress showed no significant differences between both groups. Significantly lower plasma concentrations of phosphatidylcholine, phosphatidylethanolamine, lyso-phosphatidylethanolamine (all p < 0.05) and their corresponding ether-linked analogs were observed, which were all reduced in obese participants compared to the control group. Pre-operative assessment of micronutrients in patients undergoing bariatric surgery is recommended for early identification of patients who might be at higher risk to develop a severe micronutrient deficiency post-surgery. Assessment of plasma BCAAs and phospholipids in obese patients might help to differentiate between metabolic healthy patients and those with metabolic disorders.

Secondary Hyperparathyroidism Before and After Bariatric Surgery: a Prospective Study with 2-Year Follow-Up

PURPOSE

Secondary hyperparathyroidism (SHPT) is linked to obesity. Bariatric surgery may be associated with calcium and vitamin D deficiencies leading to SHPT. This study aimed to detect the prevalence of SHPT before and after bariatric surgery.

METHODS

This prospective study assessed the prevalence of SHPT after sleeve gastrectomy (SG, n = 38) compared to one-anastomosis gastric bypass (OAGB, n = 86). All patients were followed up for 2 years. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry.

RESULTS

Of the 124 patients, 71 (57.3%) were females, and 53 (42.7%) were males, with a mean age of 37.5 ± 8.8 years. Before surgery, 23 patients (18.5%) suffered from SHPT, and 40 (32.3%) had vitamin D deficiency. The prevalence of SHPT increased to 29.8% after 1 year and 36.3% after 2 years. SHPT was associated with lower levels of vitamin D and calcium and higher reduction of BMD in the hip but not in the spine. After 2 years, SHPT was associated with a significantly lower T-score in the hip. SHPT and vitamin D deficiency were significantly more common in patients subjected to OAGB compared to SG (p = 0.003, and p < 0.001, respectively). There is a strong negative correlation between vitamin D levels and parathormone levels before and after surgery.

CONCLUSION

Prevalence of SHPT is high in obese patients seeking bariatric surgery, especially with lower vitamin D levels. Bariatric surgery increases the prevalence of SHPT up to 2 years. Gastric bypass is associated with a higher risk of developing SHPT compared to SG.