Effect of gastric bypass surgery on vitamin D nutritional status

Changes in Nutritional Outcomes After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis

BACKGROUND

Bariatric surgery (BS) is the most effective treatment for severe obesity and it has beneficial effects on glycemic control and metabolism outcomes. However, the effects of BS on nutritional outcomes are controversial. Therefore, we aimed to evaluate the changes in several nutritional outcomes after Roux-en-Y gastric bypass (RYGB).

METHODS

A comprehensive search was performed using the following databases: PubMed, Embase, Web of Science, Cochrane Library, WanFang and Chinese National Knowledge Infrastructure. The following outcomes were evaluated: vitamin A, 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, parathormone (PTH), iron, ferritin, vitamin B12, folate, and zinc. The pooled outcomes were expressed as standard mean difference (SMD) and 95% confidence interval (CI) using a random effects model.

RESULTS

Fifty-six studies including 5645 individuals with obesity met the inclusion criteria. Serum 25(OH)D (SMD = 0.78, 95%CI 0.38 to 1.20, P < 0.001), phosphorus (SMD = 0.48, 95%CI 0.22 to 0.74, P < 0.001), PTH (SMD = 0.35, 95%CI 0.11 to 0.59, P = 0.005), vitamin B12 (SMD = 1.11, 95%CI 0.41 to 1.80, P = 0.002), and folate (SMD = 1.53, 95%CI 0.77 to 2.28, P < 0.001) significantly increased after RYGB compared with the baseline. Serum ferritin (SMD =  - 1.67, 95%CI - 2.57 to - 0.77, P < 0.001), vitamin A (SMD =  - 0.64, 95%CI - 0.99 to - 0.29, P < 0.001), and plasma zinc (SMD =  - 0.58, 95%CI - 1.09 to - 0.06, P = 0.027) significantly decreased after RYGB. No significant changes in serum calcium (SMD =  - 0.14, 95%CI - 0.40 to 0.11, P = 0.219) and iron (SMD = 0.26, 95%CI - 0.11 to 0.64, P = 0.165) were observed after RYGB.

CONCLUSIONS

Despite the increased levels of 25(OH)D, phosphorus, vitamin B12 and folate, this meta-analysis revealed the unfavorable nutritional consequences after RYGB.

Prevalence of Micronutrient Deficiencies in Preoperative Bariatric Patients in a New Zealand Tertiary Centre

PURPOSE

A potential complication of bariatric surgery is development of nutritional deficiencies. Study aims were to assess prevalence of micronutrient deficiencies in preoperative bariatric patients and to examine for ethnic differences.

METHODS

Retrospective analysis of 573 patients that underwent bariatric surgery at Counties Manukau District Health Board was carried out. Mean preoperative levels of albumin, calcium, phosphate, folate, vitamin B12, vitamin D, magnesium, haemoglobin, haematocrit, mean cell volume, mean cell haemoglobin, ferritin, iron, and transferrin were calculated. Chi square, fisher exact test, and multiple logistic regression was used to assess for differences in prevalence of micronutrient deficiencies across ethnicities.

RESULTS

The most common micronutrient deficiency was vitamin D (30.85%). There were statistically significant differences in vitamin D deficiency across ethnicities (p < 0.0001). Asians had the highest prevalence of vitamin D deficiency (60%), followed by Pacifica (44.57%), and Māori (31.68%). Asians were more likely to have vitamin D deficiency compared to NZ/Other Europeans (OR = 14.93, p < 0.001). Vitamin D deficiency was associated with higher BMI (OR = 1.05, p = 0.008). The second most common deficiency was iron (21.1%). Asians had the highest prevalence of iron deficiency (44%), followed by Māori (27.95%), and Pacifica (19.57%) (p = 0.0064). Compared to NZ/Other Europeans, Asians (OR = 4.26) and Māori (OR = 1.78) were more likely to be iron deficient (p = 0.004). Female gender was associated with iron deficiency (OR = 2.12, p = 0.007).

CONCLUSION

Vitamin D and iron are the most common micronutrient deficiencies among preoperative bariatric patients in this cohort and ethnic differences were seen. There may be a role for preoperative supplementation in these at-risk ethnic groups.

Racial disparities in selected micronutrient deficiencies after bariatric surgery: A systematic review

BACKGROUND

Bariatric surgery has been associated with numerous micronutrient deficiencies. Several observational studies have found that these deficiencies are more common in racially/ethnically minoritized patients.

OBJECTIVES

To conduct a systematic review to investigate whether racially/ethnically minoritized patients experience worse nutritional outcomes after bariatric surgery.

SETTING

University of Wisconsin-Madison.

METHODS

PubMed, CINAHL, PsychINFO, and Cochrane databases were queried. We searched for manuscripts that reported micronutrient levels or conditions related to micronutrient deficiencies according to race/ethnicity (White, African American/Black, and Hispanic) after laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass between 2002 and 2022. Eleven micronutrients (vitamins A, B1 [thiamine], B12, D, E, K, calcium, copper, folate, iron, and zinc), and four conditions (anemia, bone loss, fractures, and hyperparathyroidism) were assessed.

RESULTS

Abstracts from 953 manuscripts were screened; 18 full-text manuscripts were reviewed for eligibility, and ten met the inclusion criteria. Compared to White patients, African Americans had a higher prevalence of thiamine, vitamin D, and vitamin A deficiencies. There were no differences in calcium and vitamin B12 deficiencies. The other six micronutrients were not assessed according to race/ethnicity. Hyperparathyroidism was more prevalent in African Americans than White patients in the three studies that evaluated it. The prevalence of fractures was mixed. Anemia and bone loss were not evaluated according to race/ethnicity.

CONCLUSIONS

Although the literature on micronutrient outcomes following bariatric surgery according to race/ethnicity is limited, African Americans appear to experience a higher prevalence of vitamin deficiencies and associated conditions. Qualitative and quantitative research to explore these disparities is warranted.

Vitamin D status and supplementation before and after Bariatric Surgery: Recommendations based on a systematic review and meta-analysis

Bariatric surgery is associated with a postoperative reduction of 25(OH) vitamin D levels (25(OH)D) and with skeletal complications. Currently, guidelines for 25(OH)D assessment and vitamin D supplementation in bariatric patients, pre- and post-surgery, are still lacking. The aim of this work is to analyse systematically the published experience on 25(OH)D status and vitamin D supplementation, pre- and post-surgery, and to propose, on this basis, recommendations for management. Preoperatively, 18 studies including 2,869 patients were evaluated. Prevalence of vitamin D insufficiency as defined by 25(OH)D < 30 ng/mL (75 nmol/L) was 85%, whereas when defined by 25(OH)D < 20 ng/mL (50 nmol/L) was 57%. The median preoperative 25(OH)D level was 19.75 ng/mL. After surgery, 39 studies including 5,296 patients were analysed and among those undergoing either malabsorptive or restrictive procedures, a lower rate of vitamin D insufficiency and higher 25(OH)D levels postoperatively were observed in patients treated with high-dose oral vitamin D supplementation, defined as ≥ 2,000 IU/daily (mostly D3-formulation), compared with low-doses (< 2,000 IU/daily). Our recommendations based on this systematic review and meta-analysis should help clinical practice in the assessment and management of vitamin D status before and after bariatric surgery. Assessment of vitamin D should be performed pre- and postoperatively in all patients undergoing bariatric surgery. Regardless of the type of procedure, high-dose supplementation is recommended in patients after bariatric surgery.

Prevalence and associated factors of vitamin D deficiency after Roux-en-Y gastric bypass: a systematic review and meta-analysis

OBJECTS

To estimate the prevalence and associated factors of vitamin D deficiency (VDD) after Roux-en-Y gastric bypass (RYGB).

METHODS

PubMed, EMBASE, and CENTRAL were searched for relevant records from inception to 17 March 2023, using search terms: vitamin D, vitamin D3, vitamin D deficiency, hypovitaminosis D, gastric bypass, and RYGB. Studies were eligible for inclusion if they provided related data on VDD prevalence after RYGB.

RESULTS

Of the 1119 screened studies, 72 studies involving 7688 individuals were enrolled in the final analysis. The prevalence estimates of VDD after RYGB were 42%. Subgroup analyses suggested the pooled prevalence of postoperative VDD was 35% for follow-up duration less than or equal to 1 year, 43% for greater than 1 and less than or equal to 5 years, and 54% for greater than 5 years. Meta-regression showed that VDD prevalence was positively correlated with follow-up time. Also, the prevalence was higher in studies with inadequate vitamin D supplementation than in those with adequate supplementation and in Asia population than in those from South America, Europe, and North America. Other factors associated with high VDD prevalence after RYGB included high presurgical VDD prevalence, noncompliant patients, and black populations. No significant association existed between VDD and alimentary length.

CONCLUSION

VDD presented a high prevalence in patients following RYGB. It occurred more frequently with longer postoperative follow-up time. Population-specific vitamin D supplementation measures, targeted treatment for presurgical VDD, improved patient compliance, and periodical follow-ups were necessary to reduce VDD and other adverse outcomes.

The Eucalcemic Patient With Elevated Parathyroid Hormone Levels

Primary hyperparathyroidism (PHPT) is classically characterized by hypercalcemia with elevated or inappropriately normal parathyroid hormone (PTH) levels. Elevated PTH levels in the presence of normal calcium levels are not infrequently found during the evaluation of metabolic bone disorders or kidney stone disease. This can be caused by secondary hyperparathyroidism (SHPT) or normocalcemic primary hyperparathyroidism (NPHPT). NPHPT is due to autonomous parathyroid function whereas SHPT is caused by a physiologic stimulation to PTH secretion. Many medical conditions and medications can contribute to SHPT, and differentiation between SHPT and NPHPT may be difficult. Cases are presented to illustrate examples. In this paper, we review the distinction between SHPT and NPHPT as well as end organ effects of NPHPT and outcomes of surgery in NPHPT. We suggest that the diagnosis of NPHPT be made only after careful exclusion of causes of SHPT and consideration of medications that can increase PTH secretion. Further, we advise a conservative approach to surgery in NPHPT.

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.

Vitamin D: Dosing, levels, form, and route of administration: Does one approach fit all?

The 4th International Conference on Controversies in Vitamin D was held as a virtual meeting in September, 2020, gathering together leading international scientific and medical experts in vitamin D. Since vitamin D has a crucial role in skeletal and extra-skeletal systems, the aim of the Conference was to discuss improved management of vitamin D dosing, therapeutic levels and form or route of administration in the general population and in different clinical conditions. A tailored approach, based on the specific mechanisms underlying vitamin D deficiency in different diseases that were discussed, was recommended. Specifically, in comparison to healthy populations, higher levels of vitamin D and greater amounts of vitamin D were deemed necessary in osteoporosis, diabetes mellitus, obesity (particularly after bariatric surgery), and in those treated with glucocorticoids. Emerging and still open issues were related to target vitamin D levels and the role of vitamin D supplementation in COVID-19 since low vitamin D may predispose to SARS-CoV-2 infection and to worse COVID-19 outcomes. Finally, whereas oral daily cholecalciferol appears to be the preferred choice for vitamin D supplementation in the general population, and in most clinical conditions, active vitamin D analogs may be indicated in patients with hypoparathyroidism and severe kidney and liver insufficiency. Parenteral vitamin D administration could be helpful in malabsorption syndromes or in states of vitamin D resistance.Specific guidelines for desired levels of vitamin D should be tailored to the different conditions affecting vitamin D metabolism with the goal to define disease-specific normative values.

Improving vitamin D status in bariatric surgery subjects with monthly high-dose ergocalciferol

Background: Vitamin D insufficiency is common before and after bariatric surgery. Optimal supplementation to treat vitamin D insufficiency is not clearly defined. Objective: Determine if serum 25 (OH) D levels improve by the consumption of an additional monthly ergocalciferol supplement by subjects after bariatric surgery. Study design: Thirty-two subjects were randomly divided to receive an additional 100,000 IUs of ergocalciferol monthly after bariatric surgery (n=10) or standard level vitamin D supplement after bariatric surgery (n=22). Serum 25 (OH) D, calcium, and hemoglobin A1c levels were measured preoperatively and one year after bariatric surgery. Results: Mean changes in BMI at 1-year post-operation was -18.12±6.46 kg/m² in the control group versus -18.84±4.7 kg/m²; p=0.638 in the vitamin D group. One year after bariatric surgery, the mean changes from baseline in vitamin D levels were 2.69±9.4 and 12.4±17.0 ng/mL in control and intervention groups, respectively. The treated group showed a marginally higher mean increase in Vitamin D than the control group, p=0.059. Other mean changes at 1-year post-surgery that were not significantly different include calcium -0.264±0.45 and -0.21±0.509 mg/dl in control and intervention groups, respectively and Hgb A1c -1.0±1.21 and -0.95±0.071% in control and intervention groups, respectively. Conclusion: This study showed 100,000 IUs ergocalciferol once a month is a safe and effective treatment for vitamin D insufficiency in most patients having bariatric surgery.

Are There Ethnic Differences in Micronutrient Deficiencies in Preoperative Bariatric Patients? A Systematic Review and Meta-analysis

The purpose of this systematic review was to determine if in patients presenting for bariatric surgery, patients of different ethnicities, have different micronutrient deficiencies preoperatively. Databases searched were PubMed, Embase, MEDLINE and Cochrane Library. A meta-analysis of prevalence of vitamin D insufficiency (<20ng/ml) was carried out using a random effects model. Twenty-eight articles were included assessing preoperative micronutrient status across different ethnic groups. The most common micronutrient assessed was vitamin D, and the most assessed ethnicity was Caucasian. African Americans had the greatest prevalence of vitamin D insufficiency when compared to other ethnicities with a pooled prevalence and 95% confidence interval of 0.80 [0.74; 0.85]. There was a significant difference in vitamin D insufficiency when compared across ethnicities (p <0.01).

Micronutrient status in bariatric surgery patients receiving postoperative supplementation per guidelines: Insights from a systematic review and meta-analysis of longitudinal studies

The micronutrient status and optimal monitoring schedule after bariatric surgery have not been sufficiently assessed. This systematic review and meta-analysis investigated the longitudinal changes in micronutrient status after bariatric surgery. PubMed, EMBASE, and Cochrane Library were searched for articles that measured preoperative and postoperative serum micronutrient levels in patients undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Among guideline-adherent studies, the longitudinal changes in micronutrient status were investigated using weighted mean difference (WMD) using a random-effects model. Among the 82 included studies, the guideline adherence rates for micronutrient supplementation after bariatric surgery did not exceed 20%. In patients supplemented per guidelines, vitamin A significantly decreased after RYGB by -7.54 (95% confidence interval [CI], -10.16 to -4.92) μg/dl at 12-23 months, vitamin E decreased after RYGB by -2.35 (95% CI, -3.65 to -1.05) μg/dl at ≥24 months, and ferritin by -54.93 (95% CI, -77.19 to -32.67] μg/L at ≥24 months after SG, compared with baseline, with moderate level of evidence. Significant decreases in micronutrient levels at certain follow-up intervals in studies with supplementation per guidelines need to be considered to establish a post-bariatric micronutrient monitoring schedule for timely detection and management of micronutrient deficiencies.

Nutritional Status of Obese Taiwanese Before Bariatric-Metabolic Surgery and Their Serum 25-Hydroxyvitamin D Concentrations for Maximal Suppression of Parathyroid Hormone

BACKGROUND

This is the first report from Taiwan using laboratory tests to assess nutritional status of patients with obesity before bariatric-metabolic surgery. Moreover, the 25(OH)D threshold for maximal suppression of parathyroid hormone (PTH) was evaluated to offer a reference value for preoperative nutritional care.

METHODS

Inclusion criteria were Taiwanese, 18-65 years old, and with BMI ≥ 27.5 kg/m² awaiting bariatric-metabolic surgery. Anthropometric data and blood samples were collected before surgery. Serum concentrations of protein; vitamins B₁, B₁₂, folate, A, D, and E; calcium; iron; zinc; copper; selenium; PTH; and erythrocyte glutathione reductase activity coefficient (vitamin B₂ status) were measured.

RESULTS

For 52 participants with a mean BMI 37.6 ± 6.4 kg/m², vitamin D deficiency (25(OH)D < 20 ng/mL) and insufficiency (20 < 25(OH)D < 30 ng/mL) were at 73 and 22% prevalence, respectively. Secondary hyperparathyroidism (PTH ≧ 65 pg/mL) was 24% and hypocalcemia was 50% (ionized Ca < 4.5 mg/dL). Deficiency of other nutrients was sporadic (< 10%) or nil. When participants were stratified according to 25(OH)D concentrations (< 10, 10-15, 15-20, and ≥ 20 ng/mL), PTH increased at 25(OH)D < 10 ng/mL (β = 48.34, p = 0.001) after adjusting for age, gender, and BMI.

CONCLUSION

For patients with obesity before bariatric-metabolic surgery, vitamin D/calcium deficiency was the only nutritional issue that needs to be addressed in Taiwan. However, a lower cutoff point of 25(OH)D, i.e., 10 ng/mL, for vitamin D deficiency may be considered for patients before surgery.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03915158.

Vertical Sleeve Gastrectomy Has Better Weight Evolution and Serum Concentrations of Vitamin D when Compared with Roux-Y Gastric Bypass

OBJECTIVE

The objective of this study is to compare the weight evolution and serum concentrations of vitamin D in individuals undergoing Roux-en-Y Gastric Bypass (RYGB) and Sleeve after 1 follow-up year.

METHODOLOGY

Descriptive, prospective, and longitudinal study, with 108 individuals divided into 2 groups: RYGB (55 patients) and Sleeve (53), evaluated preoperatively, and at 6 and 12 postoperatively months. Anthropometric data, serum concentrations of 25(OH)D, calcium, and parathyroid hormone were analyzed.

RESULTS

The Sleeve group showed greater reductions in excess weight and excess body mass index (BMI) when compared with the RYGB group at both times (p < 0.001). Besides, after 12 months, those who had undergone the Sleeve procedure also had higher percentages of surgical success (84.4% versus 65.0%, p = 0.038). The prevalence of preoperative inadequacy of 25(HO)D in both groups was 78.7%. After 6 months, there was an increase in serum concentrations of 25(HO)D in both groups (p < 0.001), but without significant differences between the groups (p = 0.154). In the comparison between 6 and 12 months, there was only a reduction for the RYGB group (p = 0.001). Also, when comparing both groups, the means of vitamin D in patients undergoing RYGB were also lower after 12 months (p = 0.003). There was a negative correlation between vitamin D and parathyroid hormone (r = - 0.235 p = 0.030). The mean serum concentrations of calcium were adequate at all times.

CONCLUSION

Patients undergoing the Sleeve procedure had a better evolution in weight loss and are at a lower risk of vitamin D inadequacy than those undergoing RYGB.

A systematic review of the interrelation between diet- and surgery-induced weight loss and vitamin D status

Obesity is a major global health problem and has been associated with vitamin D deficiency. Intentional weight loss may alter vitamin D status and, conversely, vitamin D supplementation has been hypothesized to aid in weight loss. A systematic literature search in PubMed/Medline identified 3173 articles of which 37 studies (randomized controlled trials (RCT) [n=17], non-RCTs [n=20]) are summarized as effect of: (I) diet-induced weight loss on vitamin D status (n=7), (II) vitamin D supplementation on diet-induced weight loss (n=11), (III) surgery-induced weight loss on vitamin D status (n=15), and (IV) vitamin D supplementation after surgery-induced weight loss on vitamin D status (n=5). While all studies on the effect of diet-induced weight loss on vitamin D status have consistently reported increased vitamin D levels, the targeted percentage of weight loss that is necessary for an increase has varied between 5% and >10%. N=11 RCTs testing the effect of vitamin D supplementation observe that vitamin D supplementation does not result in increased weight loss, but may affect body fat loss. Vitamin D deficiency and subsequent hyperparathyroidism have been detected in post-surgery patients, and there is evidence that vitamin D supplementation improves these post-surgery complications. We review the current evidence addressing the role of vitamin D status and supplementation in diet- and surgery-induced weight loss. Subsequently, we highlight gaps in current research and suggest directions for future research including differences in vitamin D supplementation dosages, indoor vs. outdoor exercise, and the assessment of vitamin D status in different body pools.

Hypovitaminosis D in bariatric surgery: A systematic review of observational studies

BACKGROUND

Obesity is a public health problem that carries global and substantial social and economic burden. Relative to non-surgical interventions, bariatric surgery has the most substantial and lasting impact on weight loss. However, it leads to a number of nutritional deficiencies requiring long term supplementation.

OBJECTIVES

The aims of this paper are to review 25-hydroxyvitamin D [25(OH)D] status pre and post bariatric surgery, describe the dose response of vitamin D supplementation, and assess the effect of the surgical procedure on 25(OH)D level following supplementation.

METHODS

We searched Medline, PubMed, the Cochrane Library and EMBASE, for relevant observational studies published in English, from 2000 to April 2015. The identified references were reviewed, in duplicate and independently, by two reviewers.

RESULTS

We identified 51 eligible observational studies assessing 25(OH)D status pre and/or post bariatric surgery. Mean pre-surgery 25(OH)D level was below 30ng/ml in 29 studies, and 17 of these studies showed mean 25(OH)D levels ≤20ng/ml. Mean 25(OH)D levels remained below 30ng/ml following bariatric surgery, despite various vitamin D replacement regimens, with only few exceptions. The increase in post-operative 25(OH)D levels tended to parallel increments in vitamin D supplementation dose but varied widely across studies. An increase in 25(OH)D level by 9-13ng/ml was achieved when vitamin D deficiency was corrected using vitamin D replacement doses of 1100-7100IU/day, in addition to the usual maintenance equivalent daily dose of 400-2000IU (total equivalent daily dose 1500-9100IU). There was no difference in mean 25(OH)D level following supplementation between malabsorptive/combination procedures and restrictive procedures.

CONCLUSION

Hypovitaminosisis D persists in obese patients undergoing bariatric surgery, despite various vitamin D supplementation regimens. Further research is needed to determine the optimal vitamin D dose to reach desirable 25(OH)D levels in this population, and to demonstrate whether this dose varies according to the surgical procedure.

Vitamin D status and supplementation before and after bariatric surgery: a comprehensive literature review

BACKGROUND

Bariatric surgery is the most effective long-term weight loss method. The most common procedures are Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG). Bariatric patients are at high risk of vitamin D deficiency (VDD) and insufficiency (VDI), which are associated with skeletal and nonskeletal ailments. There is no consensus regarding the optimal treatment for VDD/VDI in bariatric patients.

OBJECTIVES

To critically examine the literature on vitamin D status (serum 25[OH]D concentrations) pre- and postbariatric surgery as well as supplementation regimens currently used.

METHODS

We searched PubMed, Embase, and Cochrane from inception to May 2015 for articles relating to vitamin D, RYGB, and VSG. Of 208 citations retrieved, 30 were included.

RESULTS

Preoperative VDD (<20 ng/mL) ranged from 13% to 90%, while VDI (<30 ng/mL) was found in up to 98%. Prevalence remained similar postoperatively and was highest after RYGB. Most studies found dosages<800 IU daily insufficient postbariatric surgery. Other studies examined the effectiveness of dosages between 1000 and 5000 IU daily, reaching similar conclusions. Several studies suggested using 50,000 IU weekly plus a daily dose. No studies reported optimization.

CONCLUSIONS

It is widely accepted that serum 25(OH)D concentrations above 30 ng/mL are optimal; however, current postbariatric vitamin D supplementation fails to raise 25(OH)D above that level universally. This review highlights both the great need and the lack of consensus on the optimal supplementation regimen (dosage and frequency) for pre- and postbariatric patients. Future studies should investigate multiple regimens and attempt to identify methods for personalizing these regimens if found necessary.

Association between body weight and composition and plasma 25-hydroxyvitamin D level in the Diabetes Prevention Program

OBJECTIVE

We examined associations between body weight and plasma 25-hydroxyvitamin D concentration (25OHD) in prediabetes and sought to estimate the impact of adiposity on these associations.

METHODS

The study was conducted in the placebo (n = 1082) and intensive lifestyle (n = 1079) groups of the Diabetes Prevention Program (DPP), a multicenter trial to prevent type 2 diabetes in adults with prediabetes. Weight and 25OHD were measured at baseline, month 6, years 1 and 2. In a subset (n = 584), visceral (VAT) and subcutaneous (SAT) adiposity were assessed by computed tomography at baseline and year 1.

RESULTS

In cross-sectional analyses, baseline body weight, total fat, VAT, and SAT were inversely associated with plasma 25OHD concentration after multivariable adjustment. VAT accounted for 40 % [95 % CI 11, 69] of the association of body weight with plasma 25OHD concentration. There was no significant contribution by total fat or SAT. Two-year changes in plasma 25OHD concentration varied inversely with changes in body weight (p < 0.0001). One-year changes in total fat, VAT, or SAT were not significant mediators of the association between change in plasma 25OHD concentration and body weight.

CONCLUSION

Our study found an inverse association between body weight and plasma 25OHD concentration at baseline and over a 2-year period in adults with prediabetes. These findings in the DPP, a weight loss intervention study, raise the possibility that weight loss increases plasma 25OHD concentration. Whether adiposity mediates this association remains inconclusive.

Post-Bariatric Body Contouring

BACKGROUND

The "epidemic" of obesity has recently been accompanied by a new "epidemic" of massive weight loss. The demand for post-bariatric contouring is rising and, as such, it is extremely important for plastic surgeons to be well versed in the treatment of these patients. Unfortunately, the problem is not solely surgical.

OBJECTIVES

The aim of this article is to understand the nutritional and psychological complications that can occur in patients following massive weight loss, to understand the anatomic deformities in massive weight loss as a means to correct those deformities surgically, and to understand the complications from post-bariatric contouring procedures in an effort to avoid them.

METHODS

This article discusses the nutritional and psychological considerations in the massive weight loss patient, anatomical considerations in this patient group, and the surgical techniques designed to address these anatomic concerns. Important pertinent studies are reviewed and discussed.

RESULTS

Anatomical changes are encountered in each region of the body: there are surgical options available to correct them, although potential complications are associated with these surgical procedures. These surgical options are reviewed as well as the risk and benefits associated with them.

CONCLUSIONS

There are many problems that need to be addressed in the massive weight loss patient prior to embarking on surgical treatment. Additionally, surgery on massive weight loss patients has unique considerations that distinguish these operations from those performed on the non-bariatric population.

Nutrient deficiencies before and after sleeve gastrectomy

BACKGROUND

Obesity is associated with nutritional deficiencies. Bariatric surgery could worsen these deficiencies. Fewer nutritional deficiencies would be seen after sleeve gastrectomy compared to the Roux-en-Y gastric bypass, but sleeve gastrectomy would also cause further deterioration of the deficiencies. The aim of this study was to determine the amount of pre-operative nutrient deficiencies in sleeve gastrectomy patients and assess the evolution of the nutritional status during the first post-operative year.

METHODS

Four hundred seven sleeve gastrectomy patients were assigned to a standardized follow-up program. Data of interest were weight loss, pre-operative nutrient status and evolution of nutrient deficiencies during the first post-operative year. Deficiencies were supplemented when found.

RESULTS

Two hundred patients completed blood withdrawal pre-operatively and in the first post-operative year. pre-operatively, 5 % of the patients were anemic, 7 % had low serum ferritin and 24 % had low folic acid. Hypovitaminosis D was present in 81 %. Vitamin A had excessive levels in 72 %. One year post-operatively, mean excess weight loss was 70 %. Anemia was found in 6 %. Low-ferritin levels were found in 8 % of the patients. Folate deficiency decreased significantly and hypovitaminosis D was still found in 36 %.

CONCLUSIONS

In this study, a considerable amount of patients suffered from a deficient micronutrient status pre-operatively. One year after surgery, micronutrient deficiencies persisted or were found de novo in a considerable amount of patients, despite significant weight loss and supplementation. Significant reductions were seen only for folate and vitamin D.

Optimization of vitamin suppletion after Roux-en-Y gastric bypass surgery can lower postoperative deficiencies: a randomized controlled trial

Iron, vitamin B12, and folic acid deficiencies are among the most common deficiencies occurring after laparoscopic Roux-en-Y gastric bypass (LRYGB). The present study evaluates the effectiveness of a specially designed multivitamin supplement (WLS Forte, FitForMe, Rotterdam, the Netherlands) specifically developed for LRYGB patients.A triple-blind, randomized, 12-month study was conducted comparing WLS forte with a standard multivitamin supplement (sMVS) containing approximately 100% of the recommended daily allowance (RDA) for iron, vitamin B12, and folic acid. WLS Forte contains vitamin B12 14000% RDA, iron 500% RDA, and folic acid 300% RDA.In total, 148 patients (74 in each group) underwent a LRYGB procedure. Baseline characteristics were similar for both groups. Per protocol analysis demonstrated that sMVS treatment was associated with a decline in ferritin (-24.4 ± 70.1 μg/L) and vitamin B12 (-45.9 ± 150.3 pmol/L) over 12 months, whereas in WLS Forte patients, ferritin remained stable (+3.2 ± 93.2 μg/L) and vitamin B12 increased significantly (+55.1 ± 144.2 pmol/L). The number of patients developing ferritin or vitamin B12 deficiency was significantly lower with WLS Forte compared with sMVS (P < 0.05). Iron deficiency (ID) was reduced by 88% after WLS Forte compared with sMVS. Adverse events related to supplement use did not occur.An optimized multivitamin supplement is safe and reduces the development of iron and vitamin B12 deficiencies after LRYGB.

Calciphylaxis: a rare but fatal delayed complication of Roux-en-Y gastric bypass surgery

Gastric bypass is a commonly used surgical procedure that has shown impressive health benefits for patients with morbid obesity. However, mineral bone abnormalities (hypocalcemia, hypovitaminosis D, and secondary hyperparathyroidism) and micronutrient (e.g., iron) deficiencies are common complications after gastric bypass surgery due to alterations in the digestive anatomy. These abnormalities, their treatments, and a number of other factors associated with obesity can set up a perfect storm to induce calciphylaxis, a rare but highly fatal condition with severe comorbid conditions. We present a fatal case of nonuremic calciphylaxis coincident with symptomatic hypocalcemia in a morbidly obese man with a history of Roux-en-Y gastric bypass surgery.

Short- and mid-term changes in bone mineral density after laparoscopic sleeve gastrectomy

BACKGROUND

Bariatric surgery is the most effective treatment for achieving a significant weight loss. Morbidities present a significant reduction after bariatric surgery, but it may also result in several health complications, related to nutritional deficiencies, including bone metabolism. Several studies have reported a decrease in bone mineral density (BMD), but most of them referring to malabsorptive procedures. Restrictive procedures do not imply changes in gastrointestinal anatomy, so that one may expect fewer metabolic disturbances.

METHODS

We performed a retrospective observational study of all morbidly obese patients undergoing LSG between 2008 and 2011 at our institution. Bone densitometry was performed before surgery and 1 and 2 years after the intervention. Body size measurements, analytical variables and densitometric values in the lumbar spine (BMD, t score and z score) were investigated.

RESULTS

Forty-two patients were included, 39 females and 3 males. Mean BMI was 51.21 kg/m(2). Mean excessive BMI loss was 79.9 % after 1 year and 80.6 % after 2 years. Mean BMD values for spine increased progressively, reaching statistical significance at 1 and at 2 years. Percentage of BMD increase was 5.7 % at 1 year and 7.9 % at 2 years. An inverse correlation was observed between BMD increase and parathyroid hormone (PTH) decrease and a direct correlation between BMD and vitamin D increase.

CONCLUSION

Bone mineral density showed a progressive increase during the first and second year after sleeve gastrectomy. BMD changes are not associated with weight loss, but showed a direct correlation with vitamin D and an inverse correlation with PTH levels.

Impact of Roux-en-Y gastric bypass versus sleeve gastrectomy on vitamin D metabolism: short-term results from a prospective randomized clinical trial

PURPOSE

To assess postoperative outcomes of sleeve gastrectomy (SG) versus Roux-en-Y gastric bypass (RYGB). Short-term results on vitamin D and parathormone (PTH) metabolism are reported.

METHODS

One hundred patients were randomly assigned to RYGB (n = 45) or SG (n = 55). Vitamin D, PTH, and calcium were assessed at inclusion and after 1, 3, 6, and 12 months (M1, M3, M6, and M12). Eighty-eight patients completed 1-year follow-up.

RESULTS

Mean postoperative excess weight loss (%EWL) at M1, M3, M6, and M12 was 25.39, 43.47, 63.75, and 80.38 % versus 25.25, 51.32, 64.67, and 82.97 % in RYGB and SG, respectively. Vitamin D values were statistically significantly higher after SG compared to RYGB at M3 (61.57 pmol/L, standard deviation [SD] 14.29 vs. 54.81 SD 7.65; p = 0.01) and M12 (59.83 pmol/L, SD 6.41 vs. 56.15 SD 8.18; p = 0.02). Vitamin D deficiency rate decreased from 84.62 to 35 % at M6 (p = 0.04) and 48 % at M12 (p = 0.01) in the SG group, while there was no significant improvement in the RYGB group. Serum parathyroid hormone (sPTH) level was decreased significantly in the SG group by M3 (44.8 ng/L vs. 28.6; p = 0.03), M6 (44.9 ng/L vs. 25.8; p = 0.017), and M12 (41.4 ng/L vs. 20.5; p = 0.017). Secondary hyperparathyroidism rate was 20.83 and 24 % at M1 (p = 1), 16.67 and 8 % at M3 (p = 0.41), 14.29 and 0 % at M6 (p = 0.08), and 15 and 0 % at M12 (p = 0.23) in the RYGB and SG groups, respectively.

CONCLUSIONS

Patients after RYGB had a significantly higher postoperative vitamin D deficiency and higher sPTH levels than after SG.

Ethnic differences in weight loss and diabetes remission after bariatric surgery: a meta-analysis

OBJECTIVE

It has been postulated that the effectiveness of bariatric surgery varies between ethnic groups. However, data regarding this topic are inconclusive, as most studies included few patients from minority groups. We conducted a meta-analysis to determine the difference in percentage of excess weight loss (%EWL) 1-2 years after bariatric surgery in people of African and Caucasian descent. We also studied differences in diabetes mellitus (DM) remission.

RESEARCH DESIGN AND METHODS

We performed a MEDLINE and EMBASE search for studies reporting %EWL and/or DM remission after bariatric surgery and including both African Americans and Caucasians. The 613 publications obtained were reviewed. We included 14 studies (1,087 African Americans and 2,714 Caucasians); all provided data on %EWL and 3 on DM remission. We extracted surgery type, %EWL, and DM remission 1-2 years after surgery. After analyzing %EWL for any surgery type, we performed subanalyses for malabsorptive and restrictive surgery.

RESULTS

The overall absolute mean %EWL difference between African Americans and Caucasians was -8.36% (95% CI -10.79 to -5.93) significantly in favor of Caucasians. Results were similar for malabsorptive (-8.39% [-11.38 to -5.40]) and restrictive (-8.46% [-12.95 to -3.97]) surgery. The remission of DM was somewhat more frequent in African American patients than in Caucasian patients (1.41 [0.56-3.52]). However, this was not statistically significant.

CONCLUSIONS

In %EWL terms, bariatric surgery is more effective in Caucasians than in African Americans, regardless of procedure type. Further studies are needed to investigate the exact mechanisms behind these disparities and to determine whether ethnic differences exist in the remission of comorbidities after bariatric surgery.

Mid-term effects of sleeve gastrectomy on calcium metabolism parameters, vitamin D and parathormone (PTH) in morbid obese women

BACKGROUND

Despite routine supplementation of vitamins and minerals after bariatric surgery, an important number of patients suffer from deficiencies. Little is still known about the novel restrictive procedure, sleeve gastrectomy.

METHODS

A retrospective study of 30 morbidly obese patients undergoing a laparoscopic sleeve gastrectomy, between May 2008 and September 2010, was performed. Baseline albumin, ferritin, iron, zinc, calcium, vitamin D, parathormone (PTH), vitamin B12, and folic acid were obtained before operation and postoperative determinations 1, 3, 6, 9, 12, 18, and 24 months after surgery.

RESULTS

Before surgery, 96.7% of the patients presented vitamin D deficiency, 20% had elevated PTH, 3.3% hypoalbuminemia, and 3.3% folic acid deficiency. One year after surgery, only one patient (3.3%) presented vitamin D deficiency and had elevated PTH. The rest of parameters were within normal range. The second year after surgery, the results remain similar. A significant difference was obtained when comparing preoperative vitamin D values and postoperative determinations 12 months after surgery (increase of 51.9 ng/dl, 95% confidence interval (CI) (41.8-61.3); p < 0.001). A significant difference was determined when comparing preoperative PTH values and postoperative determinations 3 months after surgery (decrease of 16.6 pg/ml, 95% CI (2.6-30.6); p = 0.03). A significant inverse correlation was observed between weight loss and vitamin D increase at the third month after surgery (Pearson correlation coefficient -0.948; p = 0.033).

CONCLUSIONS

Postoperative values of vitamin D show a progressive increase, while PTH ones present a significant reduction, without any impact on serum calcium levels. We have demonstrated an inverse correlation between weight loss and vitamin D increase at the third month after surgery.

The link between obesity and low circulating 25-hydroxyvitamin D concentrations: considerations and implications

Obesity and vitamin D deficiency have both been recognized as major public health issues worldwide, and there is growing evidence that they are related, although the cause-effect relationship remains unclear. Could obesity be contributing to low circulating 25-hydroxyvitamin D concentrations? Alternatively, could low vitamin D status predispose to obesity? In this review, the relationship between low circulating 25-hydroxyvitamin D and obesity, and possible underlying reasons from both perspectives, is presented. One potential mechanism by which obesity could contribute to low serum 25-hydroxyvitamin D is adipose sequestration of vitamin D. On the other hand, adipose tissue has both the vitamin D receptor and the ability to synthesize 1,25-dihydroxyvitamin D, and there is evidence that vitamin D may regulate adipose tissue mass, differentiation and metabolism in ways that might contribute to obesity. Of particular interest, vitamin D deficiency is common both before and after bariatric surgery, and is often difficult to treat, particularly with the more malabsorptive procedures. Additional research is needed to elucidate the complex and multifaceted factors underlying the association between low circulating 25-hydroxyvitamin D and obesity, and to identify optimal treatment approaches in obese individuals and in bariatric surgical patients both before and after surgery.

Audit of nutritional and dietary outcomes of bariatric surgery patients

Bariatric surgery is the most effective means of achieving sustainable weight loss for the morbidly obese but resultant gastrointestinal functional changes and altered diet may lead to a number of eating and nutritional problems. This audit was conducted to evaluate Guernsey outcomes in relation to UK national standards and to determine the adequacy of current dietetic provision. A postal questionnaire was sent to 177 patients. Sixty-eight responded (48 gastric bypass, 15 banding and five other procedures). Mean body mass index preoperatively was 44.2 (five had body mass index <35). Five respondents (7%) had received preoperative and 26 post-operative dietary advice. Only 12 (18%) received any dietetic follow-up. Only one patient had any psychological support. Mean maximal weight loss and regain was 42.7 kg and 4.5 kg, respectively. Micronutrient supplementation and monitoring was variable. Deficiencies of B(12) (44%), iron (25%), vitamin D (10.2%) and folate (6.2%) were recorded. Problems with food intolerances were common and often protracted. The majority of respondents expressed satisfaction with the procedure, but many recognized that it had not solved their food-related issues. There was dissatisfaction with dietetic intervention. Overall, current treatment was shown to fall short of UK standards. A number of recommendations have been made to improve future outcomes, including re-audit and improved dietetic service provision.

Vitamin D status and supplementation in morbid obesity before and after bariatric surgery

Interest in vitamin D has increased recently because of its role on multiple biologic mechanisms and the high prevalence of deficits, particularly in obese individuals. The epidemic of morbid obesity has led to a growing number of bariatric surgical procedures, the only therapeutic modality with a reasonable chance of success on a long-term basis. Vitamin D status following bariatric surgery depends on several interacting factors and should be monitored carefully. We review vitamin D, calcium and parathyroid hormone dynamics following the main types of bariatric surgery and the guidelines for the postoperative periodic assessment and therapy.

Factors associated with secondary hyperparathyroidism in premenopausal women undergoing Roux-en-Y gastric bypass for the treatment of obesity

OBJECTIVE: To evaluate bone metabolism, bone density (BMD) and vertebral fractures in morbidly obese individuals. SUBJECTS AND METHODS: Case series of 29 premenopausal obese patients, 15 of whom had been submitted to bariatric surgery. Serum calcium, albumin, PTH and 25-hydroxy vitamin D (25OHD) were measured as well as bone densitometry of the lumbar spine and proximal femur, and lateral spine x-rays. RESULTS: High parathyroid hormone (PTH) levels were recorded in 46.6% of the surgical patients and in 21.4% of the non-surgical patients (p = 0.245); 26.7% of the former and 28.6% of the latter revealed levels 25OHD < 30 ng/mL (p = 1.000). Calcium intake was higher in the surgical group (p = 0.004) along with lower serum calcium concentrations (p = 0.019). There were no significant differences in bone mineral density (BMD) or in the prevalence of vertebral fractures between groups. CONCLUSION: In premenopausal women undergoing Roux-en-Y gastric bypass there is important intestinal calcium mal absorption which seems to be the main factor causing secondary hyperparathyroidism.

Bariatric surgery and bone metabolism: a systematic review

Few studies have demonstrated the risk of metabolic bone disease and a reduction in bone mineral density (BMD) after bariatric surgery. A systematic review was conducted of case-control and cohort studies with the aim of evaluating the relationship between bariatric surgery and bone metabolism. The search was undertaken in MedLine, covering the period from January 1997 to August 2009, using the keywords: "bariatric surgery" AND "osteoporosis", "fracture", "bone diseases", "metabolic". Six studies were included, comprising four cohort and two case-control studies. Three studies evaluated bone metabolism and BMD, and the other evaluated bone metabolism only. Based on this review, bariatric surgery is associated with alterations in bone metabolism, loss of bone mass and an increased risk of fracture. However, the maximum evaluation period covered by these studies was two years after surgery, hence the need to undertake further studies of longer duration in order to achieve a more thorough understanding of this association.

Fewer nutrient deficiencies after laparoscopic sleeve gastrectomy (LSG) than after laparoscopic Roux-Y-gastric bypass (LRYGB)-a prospective study

BACKGROUND

Deficiencies in micronutrients after bariatric operations are frequent, despite routine supplementation. Main outcome measures were pre- and postoperative frequency of nutrient deficiencies and success rate of their treatment.

METHODS

Between 5/2004 and 12/2006, 136 patients (m:f = 0:4) with an average body mass index of 45 (35-58) kg/m(2) and age of 53 (21-66) years were prospectively analysed. Laparoscopic Roux-Y-gastric bypass (LRYGB) was performed in 86 patients and laparoscopic sleeve gastrectomy (LSG) was performed in 50 patients. The patients were examined before surgery as well as 3, 6, 12, 24, 30, and 36 months postoperatively using a standard protocol including laboratory tests. The mean follow-up time was 24.4 (12-40) months; the follow-up rate was 100%.

RESULTS

Prior to surgery, 57% of the patients had at least one deficiency, 23% of whom had vitamin D(3) deficiency. Frequent postoperative deficiencies after LSG were zinc, vitamin D(3), folic acid, iron, and vitamin B(12); after LRYGB, vitamin B(12), vitamin D(3), zinc, and secondary hyperparathyroidism. No vitamin B(1) or B(6) deficiencies were found. Calcium levels were normal in all patients. Treatment of the deficiencies was mostly successful.

CONCLUSION

Preoperatively, 57% of morbidly obese patients already had a deficiency. Postoperatively, significantly more vitamin B(12) and vitamin D deficiencies and hyperparathyroidism were found in patients who had undergone LRYGB. After LSG, folate deficiency was more frequent (but not significantly so). Calcium levels were normal in all patients; therefore, parathyroid hormone and vitamin D(3) levels are more sensitive markers for early detection of disorders of calcium metabolism. Iron deficiency anaemia is most efficiently treated by IV therapy.

Utilization of preoperative patient factors to predict postoperative vitamin D deficiency for patients undergoing gastric bypass

INTRODUCTION

Vitamin D deficiency occurring after gastric bypass procedures can predispose patients to calcium and parathyroid hormone (PTH) level abnormalities. The aim of the study is to identify preoperative patient risk factors for postoperative vitamin D deficiency.

METHODS

We retrospectively reviewed patients who underwent Roux-en-Y gastric bypass procedures between 2005 and 2006. Patient demographics, laboratory values of calcium, vitamin D, and PTH were followed at quarterly intervals for 1 year.

RESULTS

One hundred forty-five patients were included in the study. The mean age for the group was 44 years with an average body mass index of 49.5 kg/m(2). Eighty-six percent of patients were female and 23% was African-American. Forty-two percent of the patients had vitamin D deficiency (<20 ng/mL) either preoperatively or at year 1. The mean calcium levels decreased from 9.39 to 9.16 mg/dL (p < 0.001) while the mean PTH levels increased from 25.7 to 43.9 ng/mL (p < 0.001). A logistic regression model recognized preoperative vitamin D levels, race, and bypass limb length to be the only significant factors (p < 0.05) for postoperative vitamin D deficiency.

CONCLUSION

It is important to recognize patients who are at risk for vitamin D deficiency before surgery so that early intervention could be in place to minimize further postoperative deficiency.

Treatment of refractory obesity in severely obese adults following management of newly diagnosed attention deficit hyperactivity disorder

OBJECTIVE

To determine whether attention deficit hyperactivity disorder (ADHD) pharmacological treatment of severely obese subjects with newly diagnosed ADHD would result in sustained weight loss.

DESIGN

Longitudinal clinical intervention study of the effects of ADHD medication on weight change over 466 days.

SUBJECTS

78 subjects (6 male, 72 female, mean age 41.3 years, BMI 42.7 kg m(-2)) out of 242 consecutively referred severely obese, weight loss refractory individuals were diagnosed as having ADHD. Sixty-five subjects received treatment and 13 remained as controls.

METHODS

Standard screening tests identified subjects likely to have ADHD. A diagnosis was made in 78 subjects by semi-structured clinical interview. ADHD subjects were screened for comorbid conditions (binge eating disorder, mood disorder, sleep apnea, chronic pain, gastroesophageal reflux disease). Satisfactory resolution of symptoms of comorbid conditions was achieved prior to the introduction of pharmacotherapy for ADHD. Subjects not accepting, tolerating or remaining on ADHD medication served as controls. Weight was measured at sequential clinic visits after initiation of pharmacotherapy.

RESULTS

Comorbid conditions were found to be highly prevalent (sleep apnea 56.4%, binge eating disorder 65.4%, mood disorder 88.4%). After an average of 466 days (s.d.=260) of continuous ADHD pharmacotherapy, weight change in treated subjects was -12.36% of initial weight and in controls +2.78%, P<0.001. Weight loss in treated subjects was 15.05 kg (10.35%) and weight gain 3.26 kg (7.03%) in controls, P<0.001.

CONCLUSIONS

ADHD is a highly prevalent condition in the severely obese population. Treatment of ADHD is associated with significant long-term weight loss in individuals with a lengthy history of weight loss failure. This result is likely because of the positive effects of treatment on self-directedness, persistence and novelty-seeking behaviors. ADHD should be considered as a primary cause of weight loss failure in the obese. Individuals seeking medical or surgical weight loss should be evaluated for ADHD and treated appropriately before intervention. This may improve the outcome for medically managed patients and avoid complications in surgical subjects because of poor compliance with diet and supplement requirements.

Finding the optimal dose of vitamin D following Roux-en-Y gastric bypass: a prospective, randomized pilot clinical trial

BACKGROUND

Vitamin D deficiency is common following bariatric surgery and is due to a combination of baseline deficiency and postoperative malabsorption. There are few prospective studies evaluating the appropriate dose of vitamin D to prevent and treat vitamin D deficiency following bariatric surgery.

METHODS

We evaluated three doses of vitamin D3 (800, 2,000, and 5,000 IU/day) in a prospective, randomized pilot trial of 45 patients undergoing Roux-en-Y gastric bypass. Serum 25 hydroxy Vitamin D (25OHD), intact PTH (iPTH), calcium, and urine calcium/creatinine ratios were measured at 6, 12, and 24 months postoperatively. Due to a high dropout rate at 24 months, we focus on the 12-month data.

RESULTS

At 12 months, the 800-, 2,000-, and 5,000-IU groups had a mean +/- SD increase in 25OHD of 27.5 +/- 40.0, 60.2 +/- 37.4, and 66.1 +/- 42.2 nmol/L, respectively (p = 0.09) with a maximum increase in each group of 87.4, 114.8, and 129.8 nmol/L. Forty-four percent, 78%, and 70% achieved 25OHD levels >or=75 nmol/L (p = 0.38). Results for the 6- and 24-month time points were similar to the 12-month results. Mean weight loss at 24 months of the study was not different among groups (p = 0.52). Serum calcium did not change significantly, and there were no cases of hypercalcemia or sustained hypercalciuria.

CONCLUSIONS

Higher doses of vitamin D supplementation trend towards higher levels of 25OHD. Vitamin D replacement as high as 5,000 IU /day is safe and necessary in many patients to treat vitamin D deficiency following Roux-en-Y gastric bypass yet is still suboptimal in others.

Treatment of vitamin D depletion after Roux-en-Y gastric bypass: a randomized prospective clinical trial

BACKGROUND

A high prevalence (60%) of vitamin D (VitD) depletion, defined as a serum 25-hydroxyvitamin D level of < or =20 ng/mL, is present in preoperative morbidly obese patients. Despite daily supplementation with 800 IU VitD and 1500 mg calcium after Roux-en-Y gastric bypass (RYGB), VitD depletion persists in almost one half (44%) of patients. However, the optimal management of VitD depletion after RYGB and the potential benefits of such treatment are currently unknown.

METHODS

A total of 60 VitD-depleted morbidly obese women were randomly assigned to receive 50,000 IU of VitD weekly after RYGB (group 1; n = 30) or no additional VitD after RYGB (group 2; n = 30). All patients received a daily supplement of 800 IU VitD and 1500 mg calcium. The serum calcium, parathyroid hormone, 25-hydroxyvitamin D, bone-specific alkaline phosphatase, urinary N-telopeptide, and bone mineral density were measured preoperatively and 1 year after RYGB. Questionnaires were used to assess other potential sources of VitD, including sunlight exposure and ingestion of VitD-containing foods/liquids.

RESULTS

At 1 year after RYGB, VitD depletion and mean 25-hydroxyvitamin D level had improved significantly in group 1 (14% and 37.8 ng/mL, respectively) compared with the values in group 2 (85% and 15.2 ng/mL, respectively; P <.001 for both). A significant 33% retardation in hip bone mineral density decline (P = .043) and a significantly greater resolution of hypertension was seen in group 1 (75% versus 32%; P = .029). No significant adverse effects were encountered from pharmacologic VitD therapy.

CONCLUSION

The results of our study have shown that 50,000 IU of VitD weekly after RYGB safely corrects VitD depletion in most women, attenuates cortical bone loss, and improves resolution of hypertension.

Nutritional deficiencies in morbidly obese patients: a new form of malnutrition? Part A: vitamins

It is a common belief that clinical vitamin or mineral deficiencies are rare in Western countries because of the low cost and unlimited diversity of food supply. However, many people consume food that is either unhealthy or of poor nutritional value that lacks proteins, vitamins, minerals, and fiber. In this, article we reviewed the literature and highlighted the vitamin deficiencies in obese patients before bariatric surgery. Deficiency of dietary minerals is described in the accompanying manuscript. The prevalence of vitamin deficiencies in the morbidly obese population prior to bariatric surgery is higher and more significant than previously believed.

Vitamin D and the bariatric surgical patient: a review

OBJECTIVE

Adiposity has been inversely associated with vitamin D concentration across a range of body mass index values and cultural groups. As obesity has increased markedly worldwide, a greater number of patients with severe obesity have been treated with gastric restrictive and/or malabsorptive surgical procedures. The purpose of this review was to describe current knowledge about vitamin D and severe obesity, and the impact of obesity surgery on vitamin D status.

RESEARCH METHODS AND PROCEDURES

A systematic review was conducted with search terms obesity, vitamin D, osteoporosis, bone disease, gastric bypass, and obesity surgery in various combinations. Publications were limited to those since 2000 to control for similarity in vitamin D assays and obesity prevalence levels.

RESULTS

Mean 25-hydroxy vitamin D was <80 nmol/l in more than 1,900 patients preoperatively, and was not restored to the optimal concentration of >80 nmol/l postoperatively. Both secondary hyperparathyroidism and bone loss were common, particularly when the obesity surgery included a malabsorptive component. Standard postsurgical supplementation with vitamin D and calcium have not been adequate to suppress secondary hyperparathyroidism or to restore 25-hydroxy vitamin D status.

DISCUSSION

The mechanisms behind vitamin D deficiency in severe obesity and evidence-based corrective actions have not been well-defined. Of particular concern are adolescents who qualify for and elect surgical treatment of their obesity, where subsequent metabolic bone disease may be long-standing.

Intensive Session: New Approaches to Medical Issues in Long-Term Care

This article, based on a series of presentations at the American Medical Directors Association, briefly highlights new advances in medical areas of interest to long-term care physicians. The areas discussed are heart failure, vitamin D, falls, new treatments for diabetes mellitus, blood pressure measurement, anemia, clinical nutrition, pressure ulcers, Clostridium difficile, insomnia, and antipsychotic therapy.