Nutrient Deficiencies Are Common Prior to Bariatric Surgery.

Obesity, defined as a body mass index >30 kg/m2, is a growing worldwide epidemic currently effecting 1 in 10 adults, with rates as high as 40% in the United States. The only proven long-term treatment of severe obesity on a population level is surgical modification of the gastrointestinal anatomy to induce weight loss, termed bariatric surgery. With adequate physician guidance and appropriate candidate criteria, bariatric surgery is an option for effective long-term treatment of obesity and its related comorbidities. Complications of bariatric surgery can be seen in patients who are not compliant to the recommended lifestyle and dietary changes required following bariatric surgery, including nausea, vomiting, dumping syndrome, acid reflux, and nutrition deficiencies. Despite caloric density, the diet of patients prior to bariatric surgery is often of poor nutrition quality and does not meet recommended dietary guidelines for micronutrient intake, making this an at-risk population for micronutrient malnutrition. Currently, improvements are needed in standardization of nutrition assessment as well as micronutrient cutoffs for deficiency and insufficiency. In the meantime, utilizing our current tools to conduct nutrition assessment at baseline and implement supplementation where necessary may improve the nutrition status of patients undergoing bariatric surgery, both before and after surgery, which may improve their surgical outcomes.

Bariatric surgery and vitamin D: key messages for surgeons and clinicians before and after bariatric surgery.

Obesity is the most widespread nutritional problem globally. Bariatric surgery is the preeminent long-term obesity treatment. Bariatric procedures manipulate the intestines to produces malabsorption and/or restrict the size of the stomach. The most enduring bariatric procedure is the Roux-en-Y gastric bypass, which utilizes both restriction (small stomach pouch) and malabsorption (duodenum bypass). The in-vogue procedure is the vertical sleeve gastrectomy - resection of the greater curvature of the stomach (predominantly restrictive). Malabsorptive procedures function by decreasing nutrient absorption, primarily fat and fat-soluble nutrients (vitamins A, D, E, and K). Most studies of vitamin D status in bariatric surgery candidates reported a prevalence of over 50% vitamin D deficiency (<50 nmol/L), enduring post-operatively with one study reporting 65% deficient at 10 years post-bariatric surgery. Obesity is associated with chronic inflammation, which may contribute to adverse surgical outcomes, e.g. poor healing and infection. Since vitamin D deficiency is also associated with chronic inflammation, obese individuals with vitamin D deficiency have extraordinary risk of adverse surgical outcomes, particularly delayed wound healing and infection due to the role of vitamin D in re-epithelialization and innate immunity. When the risk of adverse surgical outcomes in obesity is combined with that of vitamin D deficiency, there is likely an additive or potentially a synergistic effect. Furthermore, deficiency in fat-soluble vitamins, such as vitamin D, is considered a metabolic complication of bariatric surgery. Thus, determining the vitamin D status of bariatric surgery candidates and amending it preoperatively may prove greatly beneficial acutely and lifelong.

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.

C1q/TNF-Related Protein-9 (CTRP9) Levels Are Associated With Obesity and Decrease Following Weight Loss Surgery.

CONTEXT: C1q/TNF-related protein-9 (CTRP9) is a novel adipokine that has beneficial metabolic and cardiovascular effects in various animal models. Alterations in circulating CTRP9 have also been observed in patients with cardiovascular disease and diabetes, but little is known about the impact of obesity and bariatric surgery on CTRP9 concentrations. OBJECTIVE: The aim of this study was to compare CTRP9 levels in obese and lean subjects and to determine whether circulating CTRP9 levels in morbidly obese patients are altered by bariatric surgery. DESIGN, SETTING, AND PARTICIPANTS: Fifty-nine obese bariatric surgical patients and 62 lean controls were recruited to participate in a cross-sectional study at an academic medical center. The obese patients were further invited to participate in a cohort study, and 21 returned for analysis at 3 and 6 months postsurgery. INTERVENTION: Bariatric surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy) was the intervention for this study. MAIN OUTCOME MEASURES: Fasting serum was obtained from all subjects on entry to the study and was analyzed in the core laboratory for hemoglobin A1c, glucose, aspartate aminotransferase, alanine aminotransferase, total cholesterol, high- and low-density lipoprotein cholesterol, and triglycerides; CTRP9, insulin, adiponectin, and leptin were measured by ELISA. Serum from the patients in the cohort study was also analyzed at 3 and 6 months. RESULTS: Serum CTRP9 was significantly higher in the obese group compared to the lean group. CTRP9 was associated with obesity, even after controlling for age, gender, and ethnicity. Following bariatric surgery, there was a significant decrease in weight at 3 and 6 months postprocedure, accompanied by decreases in CTRP9, hemoglobin A1c and leptin, and an increase in serum adiponectin. CONCLUSIONS: CTRP9 levels are elevated in obesity and significantly decrease following weight loss surgery. Our data suggest that CTRP9 may play a compensatory role in obesity, similar to that of insulin, and is down-regulated following weight loss surgery.

Treatment for Vitamin D Deficiency Prior to Bariatric Surgery: a Prospective Cohort Study.

BACKGROUND: Since obesity increases vitamin D deficiency (VDD) risk, bariatric surgery candidates are high-risk. Previously, we documented 71.4% VDD at our center. OBJECTIVES: To investigate diagnosis and treatment for VDD in our bariatric candidates. METHODS: 25(OH)D, if pending, and supplementation (form, dosing, frequency) were prospectively documented in 265 candidates. RESULTS: Candidates were 83.0% female, 48.9% white, age 43 ± 13 years and BMI 46.3 ± 10.5 kg/m(2). 25(OH)D was available for 18.5%: 35.7% VDD 39.3% insufficiency. VDD history did not differ by demographics or procedure, as with those tested versus not. CONCLUSION: VDD testing was lower than clinically-indicated. Of those tested, 35.7% were deficient and 39.3% insufficient. We previously reported higher rates: 71.4% deficiency, 92.9% insufficiency. Thus, many candidates are untested but high-risk.

Malnutrition in Bariatric Surgery Candidates: Multiple Micronutrient Deficiencies Prior to Surgery.

BACKGROUND: Over 78 million American adults have obesity. Bariatric surgery is the leading means of durable weight loss. Nutritional deficiencies are commonly treated post-operatively but are often undiagnosed pre-operatively. Malnutrition is correlated with adverse surgical outcomes. OBJECTIVES: The aim of this study is to assess pre-operative nutritional status in our bariatric surgery candidates in a cross-sectional study. METHODS: We recruited 58 bariatric candidates approved to undergo the Roux-en Y gastric bypass. Nutritional status was determined for vitamins A, B12, D, E-α, and E-ß/γ as well as thiamine, folate, and iron. We used clinical as well as frank deficiency cut-offs based on the Institute of Medicine and the World Health Organization guidelines. RESULTS: This cohort was largely female (77.6%) and white (63.8%). Median age was 42.2 years. Median body mass index (BMI) was 46.3 kg/m(2). Multiple comorbidities (MCM) were present in 41.4%, 54.0% hypertension, 42.0% diabetic, 34.0% sleep apnea. Men had more comorbidities, 69.2 % with MCM. Folate and iron saturation varied significantly by sex. Vitamins A, D, E-α, and thiamine significantly varied by race. Vitamin D negatively correlated with BMI (p = 0.003) and age (p = 0.030). Vitamin A negatively correlated with age (p = 0.001) and number of comorbidities (p = 0.003). These pre-operative bariatric candidates had significant malnutrition, particularly in vitamin D (92.9%) and iron (36.2 to 56.9 %). Multiple micronutrient deficiency (MMND) was more common in blacks (50.0 versus 39.7% overall). Number of comorbidities did not correlate with MMND. CONCLUSIONS: Malnutrition in one or multiple micronutrients is pervasive in this pre-operative bariatric cohort. The effect of pre-operative supplementation, especially vitamin D and iron, should be explored.

Lower Circulating C1q/TNF-Related Protein-3 (CTRP3) Levels Are Associated with Obesity: A Cross-Sectional Study.

PURPOSE: C1q/TNF-related protein-3 (CTRP3) is a novel adipokine that lowers blood glucose levels, reduces liver triglyceride synthesis, and is protective against hepatic steatosis in diet-induced obese mouse models. We hypothesized that higher circulating serum levels of CTRP3 would be associated with a lean body mass index (BMI) and a more favorable metabolic profile in humans. The aim of this study was to investigate CTRP3 levels in lean individuals compared to obese individuals. METHODS: This was a cross-sectional study of obese (n=44) and lean control patients (n=60). Fasting metabolic parameters were measured in all patients and serum CTRP3 levels were measured by ELISA. RESULTS: BMI of the lean group was 21.9 ± 0.2 kg/m2 and obese group was 45.2 ± 1.1 kg/m2. We found significantly lower circulating levels of CTRP3 in obese individuals (405 ± 8.3 vs. 436 ± 6.7 ng/mL, p=0.004) compared to the lean group. Serum CTRP3 levels were inversely correlated with BMI (p=0.001), and triglycerides (p<0.001), and significantly associated with gender (p<0.01), ethnicity (p=0.05), HDL-cholesterol (p<0.01), and adiponectin (p<0.01). We found BMI (p<0.01), gender (p<0.01), and ethnicity (p<0.05) to be significant predictors of CTRP3 levels when controlling for age in multiple regression analysis. CONCLUSIONS: CTRP3 is a beneficial adipokine whose circulating levels are significantly lower in obese individuals. Obesity causes dysregulation in adipokine production, including the down-regulation of CTRP3. Lower CTRP3 levels may contribute to the pathophysiology of metabolic disorders associated with obesity. Optimizing CTRP3 levels through novel therapies may improve obesity and its comorbidities.

Performance characteristics of upper airway critical collapsing pressure measurements during sleep.

OBJECTIVE: The critical pressure (P(CRIT)), a measurement of upper airway collapsibility, is a determinant of the severity of upper airway obstruction during sleep. We examined the performance characteristics of the passive and active P(CRIT) by examining both within-night and between-night variability in the measurements. METHODS: We studied 54 sleep apnea patients (39 men, 15 women) and 34 normal subjects (20 men, 14 women) on either 1 or 2 nights during sleep. The P(CRIT) was measured during relative hypotonia ("passive" state) or during periods of sustained upper airway obstruction used to recruit upper airway neuromuscular responses ("active" state) within- and between-nights. In a subgroup of 10 normal subjects, we performed repeated measurements during hypnotic-induced sleep. Bland-Altman analyses were used to determine the within-night and between-night reliability of the P(CRIT) measurements. RESULTS: There were no significant within-night or between-night differences for the mean passive P(CRIT). The active P(CRIT) was ∼1 cm H(2)O more collapsible on the second night than on the first night. The limits of agreement, which bound the passive and active P(CRIT), was ∼ ± 3 cm H(2)O and was reduced to ∼ ± 1 cm H(2)O for the passive P(CRIT) with hypnotic-induced sleep. CONCLUSION: Passive and active P(CRIT) measurements are reasonably reliable within and between nights. An approximately 3 cm H(2)O change in passive or active P(CRIT) appears to represent the minimally significant change in P(CRIT) necessary to assess the effect of an intervention (e.g., positional therapy, surgical interventions, oral appliance effects, and pharmacotherapy) on upper airway mechanical loads or neuromuscular responses.