Role of calcium malabsorption in the development of secondary hyperparathyroidism after biliopancreatic diversion

FCH-PET/CT in primary hyperparathyroidism with discordant/negative MIBI scintigraphy and ultrasonography

CONTEXT

The contribution of [18F]F-fluorocholine (FCH)PET/CT in normocalcemic primary hyperparathyroidism (nPHPT) remains unknown.

OBJECTIVE

To evaluate the sensitivity and specificity of FCH-PET/CT in a cohort of osteoporotic nPHPT patients with discordant or negative MIBI scintigraphy and ultrasonography who all underwent parathyroidectomy (PTX).

DESIGN

Longitudinal retrospective cohort study in patients referred for osteoporosis with mild biological primary hyperparathyroidism.

SETTING

Tertiary referral center with expertise in bone metabolism and surgical management of hyperparathyroidism.

PATIENTS

Among 109 PHPT patients analyzed, three groups were individualized according to total serum calcium (tCa) and ionized calcium (iCa): 32 hypercalcemic patients (HtCa group), 39 patients with normal tCa and elevated iCa (NtCa group), and 38 patients with both normal tCa and iCa (NiCa). All patients had biochemical follow-up confirming or not the success of PTX.

MAIN OUTCOME MEASURES

To evaluate the performance of FCH-PET/CT in terms of sensitivity and specificity, and to compare with first-line imaging procedures in the setting of nPHPT.

RESULTS

The sensitivity of FCH-PET/CT was 67% in the hypercalcemic, 48% in the NtCa group (p = 0.05 vs HtCa), and 33% in the NiCa group (p = 0.004 vs HtCa). Specificity ranged from 97 to 99%. FCH-PET/CT was positive in 64.3% of patients with negative conventional imaging, with biochemical resolution after PTX in 77.8% of patients. Triple negative imaging was observed in 20 patients, with PHPT resolution in 85% of these patients.

CONCLUSION

This study highlights the contribution of [18F]F-fluorocholine PET/CT in a well phenotyped cohort of normocalcemic patients with discordant or negative findings in MIBI scintigraphy and ultrasonography. However, negative imaging in nPHTP does not rule out the possibility of surgical cure by an experienced surgeon.

Normocalcemic primary hyperparathyroidism

Normocalcemic primary hyperparathyroidism (PHPT) is a newer phenotype of PHPT defined by elevated PTH concentrations in the setting of normal serum calcium levels. It is increasingly being diagnosed in the setting of evaluation for nephrolithiasis or metabolic bone diseases. It is important to demonstrate that PTH values remain consistently elevated and to measure ionized calcium levels to make the diagnosis. A diagnosis of normocalcemic disease is one of exclusion of secondary forms of hyperparathyroidism, including vitamin D deficiency, renal failure, medications, malabsorption, and hypercalciuria. Lack of rigorous diagnostic criteria and selection bias of the studied populations may explain the different rates of bone and renal complications. The natural history still remains unknown. Caution should be used in recommending surgery, unless clearly indicated. Here we will review the diagnostic features, epidemiology, clinical presentation, natural history, medical and surgical management of normocalcemic PHPT.

European Expert Consensus on Practical Management of Specific Aspects of Parathyroid Disorders in Adults and in Pregnancy: Recommendations of the ESE Educational Program of Parathyroid Disorders

This European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders (PARAT) in 2019, were discussed during two virtual workshops in 2021, and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosing to familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represent areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT, need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborns children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed for a broader clinical audience, and were developed with focus on endocrinologists in training.

[The clinical practice guidelines for primary hyperparathyroidism, short version]

Primary hyperparathyroidism (PHPT) is an endocrine disorder of parathyroid glands characterized by excessive secretion of parathyroid hormone (PTH) with an upper normal or elevated blood calcium level. Classical PHPT refers to a symptomatic, multi-system disorder, wich can lead to a significant decrease in the quality of life, disability of patients, and even an increased risk of premature death. Hypercalcemia and the catabolic effect of PTH on various cells are considered as the main pathogenetic mechanisms of the PHPT associated complications. In the last two decades, there has been an increase in the incidence of PHPT, mainly due to the mild forms of the disease, primarily due to the routine calcium screening in North America, Western Europe and, Asia. High prevalence of the disease, as well as the variety of clinical manifestations, cause the attention of different specialists - physicians, rheumatologists, urologists, nephrologists, cardiologists and other doctors. This review cover the main issues of Russian guidelines for the management of PHPT, approved in 2020, including laboratory and instrumental methods, differential diagnosis, surgical and conservative approach, short-term and long-term follow-up. This guidelines also include the recommendations for special groups of patients with hereditary forms of PHPT, parathyroid carcinoma, PHPT during pregnancy.

Nutritional Assessment and Preparation for Adult Bariatric Surgery Candidates: Clinical Practice

Bariatric surgery (BS) has proven to be highly efficacious in the treatment of obesity and its comorbidities. However, careful patient selection is critical for its success. Thus, patients should undergo medical, behavioral, and nutritional assessment by a multidisciplinary team. From the nutritional point of view, BS candidates should undergo nutritional assessment, preparation, and education by a registered dietitian in the preoperative period. Currently, detailed specified and comprehensive information on these topics is lacking. The present narrative review aimed to summarize the available literature concerning both the preoperative nutritional assessment components and the preoperative nutritional preparation and education components of patients planning to undergo BS. Current literature indicates that proper management before BS should include a comprehensive nutritional assessment, in which it is advisable to perform a clinical interview to assess patients' medical background, weight management history, eating patterns and pathologies, oral health, physical activity habits, nutritional status, supplementation usage, BS knowledge, surgery expectations and anthropometric measurements. Nutritional preparation and educational strategies should include an individualized preoperative weight-loss nutrition program, improvement of glycemic control, micronutrients deficiencies correction, eating and lifestyle habits adaptation, physical activity initiation, and strengthening knowledge on obesity and BS. At this stage, more well-designed intervention and long-term cohort studies are needed in order to formulate uniform evidence-based nutritional guidelines for patients who plan to undergo BS, including populations at higher nutritional risk. Moreover, postoperative outcomes of presurgical nutritional intervention programs should be studied.

Trends in Serum Vitamin D Levels within 12 Months after One Anastomosis Gastric Bypass (OAGB)

PURPOSE

To assess serum vitamin D trend from baseline to 12 months after one anastomosis gastric bypass (OAGB).

MATERIALS AND METHODS

In this observational cohort analysis of longitudinal data, we assessed the trend of serum vitamin D, and its associations with anthropometric, and biochemical measurements in 98 patients undergoing OAGB in a bariatric surgery center. All participants were on >800 IU/day vitamin D supplementation.

RESULTS

Vitamin D, lipid profile, creatinine, and albumin levels significantly improved at 12 months post-surgery. Vitamin D concentrations significantly increased from 26.52 ± 12.32 to 54.52 ± 27.90 ng/mL at 12 months. The correlations between vitamin D concentrations and weight, body mass index, lipid profile, ferritin, glycemic indices, and albumin were not significant. In addition, the correlations between vitamin D and parathormone, vitamin D receptor, calcium, phosphorus, body composition, and basal metabolic rate (BMR) did not reach the threshold of statistical significance at 12 months following bariatric surgery. Although there was a significant correlation between body weight and body composition (P < 0.001) and basal metabolic rate (BMR) (r = 0.762, P < 0.001) at 12 months, there were no significant correlations between weight change percent and body composition (P > 0.05), BMR (r = -0.101, P = 0.350), and vitamin D (r = 0.120, P = 0.271) at 12 months.

CONCLUSION

Our results showed that supplementation of vitamin D with dosage of >800 IU/day is sufficient for prevention of vitamin D deficiency within 12 months after OAGB surgery. Note: This data is mandatory.

Normocalcaemic primary hyperparathyroidism: An update on diagnostic and management challenges

Normocalcaemic primary hyperparathyroidism is a condition that can present with intermittent hypercalcemia or may evolve into hypercalcemic primary hyperparathyroidism. This milder biochemical entity remains incompletely understood because of a lack of long-term health outcomes regarding both medical and surgical approaches to its management. Medical therapies have shown some efficacy. A limited number of studies have found that bisphosphonates increase bone mineral density, and calcimimetics may decrease the risk of nephrolithiasis in patients with normocalcaemic primary hyperparathyroidism. Studies have also described patient outcomes after applying the same surgical criteria used for patients with hypercalcaemic primary hyperparathyroidism to those with the normocalcaemic form of the disease. These studies suggest that parathyroid surgery appears to be effective in normalizing elevated serum parathyroid hormone concentrations and decreasing adverse renal and skeletal outcomes in patients with normocalcaemic hyperparathyroidism. Given the available data and overall lack of consensus regarding the optimal management of these patients, a reasonable approach is to tailor treatment to the individual patient by considering their risk factors for new or accelerated bone loss, kidney stones, diminished quality of life, and cardiovascular disease.

Bone Health following Bariatric Surgery: Implications for Management Strategies to Attenuate Bone Loss

Bariatric surgery (BS) is an effective treatment for morbid obesity and its associated comorbidities. Following such a procedure, however, patients are at risk of developing metabolic bone disease owing to the combination of rapid weight loss, severely restricted dietary intake, and reduced intestinal nutrient absorption. Patients undergoing malabsorptive procedures are at a higher risk of postoperative bone health deterioration than those undergoing restrictive procedures; however, studies have demonstrated negative skeletal consequences of restrictive procedures as well. The clinical practice guidelines of some international associations have previously addressed preoperative evaluation and postoperative clinical care in order to maintain bone health in BS patients. Nevertheless, some issues regarding bone health in BS patients remain unclear owing to the lack of relevant randomized clinical trials, including doses of nutritional supplements pre- and post-BS. This review summarizes the current data regarding the skeletal consequences of BS and its mechanisms, with an emphasis on the preventive strategies and nutritional care that may be warranted in order to attenuate bone deterioration following BS.

Serum Bioavailable Vitamin D Concentrations and Bone Mineral Density in Women After Obesity Surgery

INTRODUCTION

Low bone mass after obesity surgery may arise as a consequence of chronic malabsorption of calcium and vitamin D. However, we have not found any role of serum 25-hydroxyvitamin D or of polymorphisms in the vitamin D receptor gene in previous studies.

PURPOSE

To investigate the circulating bioavailable 25-hydroxyvitamin D in women after bariatric procedures and its association with bone mass.

PATIENTS AND METHODS

The study consisted of 91 women on follow-up for 7 ± 2 years after bariatric surgery. We measured bone mineral density (BMD), serum parathormone (PTH), 25-hydroxyvitamin D, and vitamin D binding protein (VDBP). All patients were genotyped for two variants in the coding region of VDBP (rs4588 and rs7041). Bioavailable 25-hydroxyvitamin D was calculated in double homozygotes.

RESULTS

We found a negative correlation between bioavailable 25-hydroxyvitamin D and PTH (r = -0.373, P = 0.018), but not with BMD at lumbar spine (r = -0.065, P = 0.682) or hip (r = -0.029, P = 0.857). When adjusting by age, similar results were found for PTH (r = -0.441, P = 0.005), BMD at lumbar spine (r = -0.026, P = 0.874) and hip (r = -0.096, P = 0.561). After multivariate linear regression, forcing bioavailable 25-hydroxyvitamin D into the model resulted in a weak significant association with BMD at the lumbar spine (β = - 0.247, P = 0.025).

CONCLUSIONS

Serum bioavailable 25-hydroxyvitamin D concentrations are not associated with bone mass loss after bariatric surgery in women. The negative association with serum PTH levels suggests that vitamin D supplementation partly improves secondary hyperparathyroidism, yet other mechanisms may contribute to low bone mass after bariatric surgery.

Bilateral insufficiency hip fractures after bariatric surgery

Bariatric surgery is one of the most common surgeries within developed countries due to the increase in morbid obesity that has been observed in the past decades. The short-term alterations in the metabolism of calcium and vitamin D are well known after these procedures; however, the clinical and biochemical consequences may not be detected for years or even remain undiagnosed. We present the first case of bilateral insufficiency hip fracture after years of bariatric surgery. Although this is a long-term and rare complication, with the high number of gastric bypass performed in the past years, the number of these cases could increase with time. Moreover, it is important as an undiagnosed hip fracture can cause a displacement that could need an arthroplasty, with all the complications that entails. For that reason, this long-term complication highlights the need to reevaluate the optimal follow-up of these patients and the importance to continue monitoring metabolic bone diseases in the prevention of insufficiency fractures.

Revision of Biliopancreatic Diversion for Side Effects or Insufficient Weight Loss: Codification of a New Procedure

PURPOSE

Addressing the problem of proctologic sequelae after Scopinaro's classical BPD, we elongated the common limb from 50 to 200 cm at the expense of the alimentary limb and simultaneously, with the aim of avoiding weight regain, reduced the gastric pouch from 500 to 40 ml. After increased experience with the new procedure, we observed a favourable tendency towards further weight loss. Thus, we subsequently extended the indication to the procedure to patients with unsatisfactory weight loss after Scopinaro's classical BPD (SBPD).

METHODS

We retrospectively reviewed our clinical experience with the new procedure.

RESULTS

From March 2008 to December 2014, 38 patients were submitted to the revisional procedure. The indication to surgical revision was proctologic in 26 patients and unsatisfactory weight loss in 12. After the revisional procedure, a significant reduction in bowel movements per day was observed, together with a significant reduction in body weight (from preoperative 87.1 ± 21 to 69.2 ± 13.5 kg at post-operative year 1 and 68.1 ± 11.9 kg at year 5; p < 0.001) and a parallel reduction in BMI (from preoperative 33.03 ± 7.6 to 26.8 ± 4.1 at post-operative year 1 and 26.9 ± 2.8 at year 5; p < 0.001). Mean excess BMI percent loss was 49.5 ± 94.6% at post-operative month 3, 76.51 ± 74.9% at year 1 and 76.2 ± 31.3% at year 5. Nutritional and metabolic parameters remained stable. Similar results were observed, analysing separately both groups of patients.

CONCLUSIONS

Our preliminary data suggest that the proposed procedure could represent a safe and effective revisional tool to treat invalidating proctologic sequelae after SBPD, or when weight loss may be deemed unsatisfactory.

The role of serum osteoprotegerin and receptor-activator of nuclear factor-κB ligand in metabolic bone disease of women after obesity surgery

Metabolic bone disease may appear as a complication of obesity surgery. Because an imbalance in the osteoprotegerin and receptor-activator of nuclear factor-κB ligand system may underlie osteoporosis, we aimed to study this system in humans in the metabolic bone disease occurring after obesity surgery. In this study we included sixty women with a mean age of 47 ± 10 years studied 7 ± 2 years after bariatric surgery. The variables studied were bone mineral density, β-isomer of C-terminal telopeptide of type I collagen cross-links (a bone resorption marker), the bone formation markers osteocalcin and N-terminal propeptide of procollagen 1, serum osteoprotegerin and receptor-activator of nuclear factor-κB ligand. Serum osteoprotegerin inversely correlated with the bone remodeling markers osteocalcin, β-isomer of C-terminal telopeptide of type I collagen cross-links and N-terminal propeptide of procollagen 1. The osteoprotegerin and receptor-activator of nuclear factor-κB ligand ratio also correlated inversely with serum parathormone and osteocalcin. Bone mineral density at the lumbar spine was associated with age (β = -0.235, P = 0.046), percentage of weight loss (β = 0.421, P = 0.001) and osteoprotegerin and receptor-activator of nuclear factor-κB ligand ratio (β = 0.259, P = 0.029) in stepwise multivariate analysis (R ² = 0.29, F = 7.49, P < 0.001). Bone mineral density at the hip site was associated only with percentage of weight loss (β = 0.464, P < 0.001) in stepwise multivariate regression (R ² = 0.21, F = 15.1, P < 0.001). These data show that the osteoprotegerin and receptor-activator of nuclear factor-κB ligand system is associated with bone markers and bone mineral density at the lumbar spine after obesity surgery.

Presence of Serum Ferritin before and after Bariatric Surgery: Analysis in Dentate and Edentulous Patients

Society has changed its own lifestyle, specially its eating habits and physical activities, leading to excessive weight and a sedentary behavior, which has contributed to obesity increase. Bariatric surgery is the most effective treatment to obesity, allowing weight loss and its maintenance. However, it has been related high levels of iron deficiency after surgery. A person's nutritional status might be affected by total or partial tooth loss. The aim of this longitudinal prospective cohort study was to evaluate the levels of serum ferritin before and after bariatric surgery and to identify if there is a relation with tooth loss. The sample was composed of 50 patients selected and assisted at Amaral Carvalho Hospital, located in Jaú city, Brazil. The use and necessity of prosthesis, dental absence or presence, and serum ferritin dosage were evaluated. Student's t test, Univariate analysis, Chi-square and Odds Ratio were adopted (p<0.05). There was no significant difference regarding the serum ferritin levels between dentate and edentulous patients prior to surgery (p = 0.436). After surgery, the serum ferritin levels were higher in edentulous patients (prosthesis users) when compared to the pre-surgical levels, and the post-surgical levels presented significant difference regarding the dentate patients (p = 0.024). It can be concluded that rehabilitated patients in postoperative period showed better levels of serum ferritin after surgical intervention.

Effects of bariatric surgery on male obesity-associated secondary hypogonadism: comparison of laparoscopic gastric bypass with restrictive procedures

Bariatric surgery results in the complete resolution of male obesity-associated secondary hypogonadism (MOSH) in many patients. However, the effects of different bariatric surgical procedures on male sexual hormone profiles and sexual dysfunction have not been compared to date. We compared the pre- and post-operative (at least 6 months after initial surgery) sex hormone profiles of 20 severely obese men submitted to laparoscopic gastric bypass (LGB) with 15 similar patients submitted to restrictive techniques (sleeve gastrectomy in 10 and adjustable gastric banding in 5). We calculated free testosterone (FT) levels from total testosterone (TT) and sex hormone binding globulin (SHBG) concentrations. Fasting glucose and insulin levels served for homeostatic model assessment of insulin resistance (HOMAIR). MOSH was present in 25 and 16 of the 35 patients when considering TT and FT concentrations respectively, resolving after surgery in all but one of them. When considering all obese men as a whole, patients submitted to LGB or restrictive procedures did not differ in terms of excess weight loss, in the decrease of fasting glucose and insulin, HOMAIR and waist circumference, or in the increase of serum 25-hydroxyvitamin D, TT and FT levels. The improvement in TT correlated with the decrease in fasting glucose (r = -0.390, P = 0.021), insulin (r = -0.425, P = 0.015) and HOMAIR (r = -0.380, P = 0.029), and with the increase in SHBG (r = 0.692, P < 0.001). The increase in FT correlated with the decrease in fasting glucose (r = -0.360, P = 0.034). LGB and restrictive techniques are equally effective in producing a remission of MOSH.

Effects of alendronate and vitamin D in patients with normocalcemic primary hyperparathyroidism

No data on the pharmacological treatment of normocalcemic hyperparathyroidism (NPHPT) are available. We treated 30 NPHPT postmenopausal women with alendronate/cholecalciferol (treated group) or vitamin D alone (control group). Over 1 year, bone mineral density (BMD) increased significantly in treated group, but not in control group. Both treatments did not affect serum or urinary calcium.

INTRODUCTION

Normocalcemic primary hyperparathyroidism (NPHPT) is defined by normal serum calcium and consistently elevated PTH levels after ruling out the causes of secondary hyperparathyroidism. It is likely that subjects with NPHPT may develop kidney and bone disease. As no data on the pharmacological treatment of NPHPT are available, we aimed to investigate the effects of alendronate and cholecalciferol on both BMD and bone biochemical markers in postmenopausal women with NPHPT. Safety of vitamin D was evaluated as secondary endpoint.

METHODS

The study was a prospective open label randomized trial comparing 15 postmenopausal women with NPHPT (PMW-NPHPT), treated with oral alendronate plus cholecalciferol (treated group) and 15 PMW-NPHPT treated only with cholecalciferol (control group). Blood samples were obtained at baseline and after 3, 6, and 12 months. Bone turnover markers (BTM) were measured at baseline, 3, and 6 months, respectively. BMD was assessed at baseline and after 12 months.

RESULTS

After 1 year of treatment, BMD increased significantly at the lumbar, femoral neck, and hip level in the treated group, but not in the control group (p = 0.001). No differences were found between or within groups in serum calcium, PTH, and urinary calcium levels. BTM significantly decreased in the treated group but not in the control group, at 3 and 6 months (p < 0.001), respectively. No cases of hypercalcemia or hypercalciuria were detected during the study.

CONCLUSION

The results of this study indicate that alendronate/cholecalciferol increases BMD in postmenopausal women with NPHPT. Alendronate/cholecalciferol or vitamin D alone does not affect serum or urinary calcium.

Skeletal effects of bariatric surgery: examining bone loss, potential mechanisms and clinical relevance

Bariatric surgery is the most effective therapeutic approach to morbid obesity, resulting in substantial weight loss and improved cardiometabolic profiles; however, a growing body of evidence suggests that bariatric procedures increase both skeletal fragility and the risk of related future fracture secondary to excessive bone loss. Prospective evidence shows that areal bone mineral density (BMD) assessed by dual energy X-ray absorptiometry (DXA) declines by as much as 14% in the proximal femoral regions, including the femoral neck and total hip, 12 months postoperatively. Lumbar spine areal BMD outcomes show greater 12-month postoperative variability across surgical procedures (-8 to +6%) and contrast with no change in volumetric BMD outcomes measured by quantitative computed tomography. Diminished mechanical loading, micronutrient deficiency and malabsorption, along with neurohormonal alterations, offer plausible underlying mechanisms to explain these observed post-bariatric bone changes, but most remain largely unsubstantiated in this population. Importantly, DXA-based skeletal imaging may have limited utility in accurately detecting bone change in people undergoing bariatric surgery; partly because excessive tissue overlying bone increases the variability of areal BMD outcomes. Moreover, a paucity of fracture and osteoporosis incidence data raises questions about whether marked post-bariatric surgery bone loss is clinically relevant or a functional adaptation to skeletal unloading. Future studies that use technology which is able to accurately capture the site-specific volumetric BMD and bone architectural changes that underpin bone strength in people undergoing bariatric surgery, that consider mechanical load, and that better quantify long-term fracture and osteoporosis incidence are necessary to understand the actual skeletal effects of bariatric surgery.

Review article: The nutritional and pharmacological consequences of obesity surgery

BACKGROUND

Obesity surgery is acknowledged as a highly effective therapy for morbidly obese patients. Beneficial short-term effects on common comorbidities are practically undisputed, but a growing data pool from long-term follow-up reveals increasing evidence of potentially severe nutritional and pharmacological consequences.

AIMS

To assess the prevalence, causes and symptoms of complications after obesity surgery, to elucidate and compare therapy recommendations for macro- and micronutrient deficiencies, and to explore surgically-induced effects on drug absorption and bioavailability, discussing ramifications for long-term therapy and prophylaxis.

METHODS

PubMed, Embase and MEDLINE were searched using terms including, but not limited to, bariatric surgery, gastric bypass, obesity surgery and Roux-en-Y, coupled with secondary search terms, e.g. anaemia, micronutrients, vitamin deficiency, bacterial overgrowth, drug absorption, pharmacokinetics, undernutrition. All studies in English, French or German published January 1980 through March 2014 were included.

RESULTS

Macro- and micronutrient deficiencies are common after obesity surgery. The most critical, depending on surgical technique, are hypoalbuminemia (3-18%) and deficiencies of vitamins B1 (≤49%), B12 (19-35%) and D (25-73%), iron (17-45%) and zinc (12-91%). Many drugs commonly administered to obese patients (e.g. anti-depressants, anti-microbials, metformin) are subject to post-operative and/or PPI-associated changes affecting bioavailability and absorption.

CONCLUSIONS

Complications are associated with pre-operative and/or post-operative malnutrition or procedure-related changes in intake, absorption and drug bioavailability. The high prevalence of nutrient deficiencies after obesity surgery makes life-long nutritional monitoring and supplementation essential. Post-operative changes to drug absorption and bioavailability in bariatric patients cast doubt on the validity of standard drug dosage and administration recommendations.

Secondary hyperparathyroidism, vitamin D sufficiency, and serum calcium 5 years after gastric bypass and duodenal switch

BACKGROUND

The prevalence of secondary hyperparathyroidism (SHPT) is high after bariatric surgery. Vitamin D is supplied to counteract SHPT and bone disease, and we studied vitamin D associations with SHPT.

METHODS

We measured serum levels of 25-OH vitamin D and parathyroid hormone (PTH) 5 years after gastric bypass and duodenal switch. One hundred twenty-five patients were included, of whom 114 (91 %) had undergone gastric bypass and 11 (9 %) had undergone duodenal switch. SHPT was defined as PTH > 7.0 pmol/l in the absence of hypercalcemia. 25-OH vitamin D levels were divided into three categories: <50, 50-74, and ≥75 nmol/l. Serum ionized calcium, magnesium, phosphate, and creatinine were divided into tertiles.

RESULTS

Mean age ± SD was 44 ± 9 years at 5 years follow-up. Ninety out of 125 (72 %) patients were women. SHPT was present in 45 out of 114 (40 %) gastric bypass patients and in 11 out of 11 (100 %) duodenal switch patients. The prevalence was high in all vitamin D categories studied. An inverse association between ionized calcium and PTH was found. For the gastric bypass patients, the odds ratio for SHPT in the upper two tertiles of ionized calcium was 0.35; 95 % CI, 0.15-0.79; p = 0.011, compared with the lowest tertile. Supplements of vitamin D and calcium were not associated with a lower prevalence of SHPT at 5 years follow-up.

CONCLUSIONS

The prevalence of SHPT was high 5 years after gastric bypass and duodenal switch. SHPT was inversely associated with serum ionized calcium, but not with vitamin D. The supplementation used was insufficient to compensate for the impaired calcium absorption after surgery.

Systemic consequences of bariatric surgery and its repercussions on oral health

INTRODUCTION

Morbid obesity control can be done by bariatric surgery that restricts or reduces the amount of food absorption. The objective of this review was to identify the consequences of bariatric surgery and its repercussions on oral health.

METHOD

It was used the Virtual Library of Health, which included articles that had any direct or indirect connection between bariatric surgery and oral health, and published in the last ten years.

RESULTS

Some complications of the surgery are chronicle reflux and nutritional deficiency, which may bring repercussions on the oral cavity, such as tooth erosion, bone loss and dental caries. On the other hand, there are also positive impacts, such as the decrease of diabetes, apnea and improvement on self-esteem, that makes the patients less vulnerable to complications regarding oral health, for example xerostomy and periodontal disease.

CONCLUSION

Maintaining proper oral health in patients undergoing bariatric surgery contributes to success after surgery protecting benefits and minimizing side effects.

Normocalcemic primary hyperparathyroidism

Primary hyperparathyroidism, a common endocrine disorder, is traditionally defined by hypercalcemia and elevated levels of parathyroid hormone (PTH). A newer presentation of primary hyperparathyroidism has been described over the past decade, in which PTH is elevated but serum calcium is consistently normal, in the absence of secondary causes of hyperparathyroidism, such as renal disease or vitamin D deficiency. Recognition of this phenotype of primary hyperparathyroidism, normocalcemic primary hyperparathyroidism, supports a biphasic chronological time course in some individuals in which PTH levels are first elevated but serum calcium is normal, followed by the development of frank hypercalcemia. This review focuses on the available literature regarding this newly described phenotype of primary hyperparathyroidism.

Effects of bilio-pancreatic diversion on diabetic complications: a 10-year follow-up

OBJECTIVE

The surgical option could represent a valid alternative to medical therapy in some diabetic patients. However, no data are available on long-term effects of metabolic surgery on diabetic complications. We aimed to determine whether patients with newly diagnosed type 2 diabetes who underwent bilio-pancreatic diversion (BPD) had less micro- and macrovascular complications than those who received conventional therapy.

RESEARCH DESIGN AND METHODS

This was an unblinded, case-controlled trial with 10-years' follow-up, conducted from July 1998 through October 2009 at the Day Hospital of Metabolic Diseases, Catholic University, Rome, Italy. A consecutive sample of 110 obese patients (BMI >35 kg/m(2)) with newly diagnosed type 2 diabetes was enrolled. The study was completed by 50 subjects. The main outcome measure was long-term effects (10 years) of BPD versus those associated with conventional therapy on microvascular outcome, micro- and macroalbuminuria, and glomerular filtration rate (GFR). Secondary measures included macrovascular outcomes, type 2 diabetes remission, glycated hemoglobin, and hyperlipidemia.

RESULTS

Ten-year GFR variation was -45.7 ± 18.8% in the medical arm and 13.6 ± 24.5% in the surgical arm (P < 0.001). Ten-year hypercreatininemia prevalence was 39.3% in control subjects and 9% in BPD subjects (P = 0.001). After 10 years, all BPD subjects recovered from microalbuminuria, whereas microalbuminuria appeared or progressed to macroalbuminuria in control subjects. Three myocardial infarctions, determined by electrocardiogram, and one stroke occurred in control subjects. After the 10-year follow-up, coronary heart disease (CHD) probability was 0.22 ± 0.10 and 0.05 ± 0.04 in the medical and surgical groups, respectively (P < 0.001). Remission from type 2 diabetes was observed in all patients within 1 year of surgery. Surgical and medical subjects had lost 34.60 ± 10.25 and 0.38 ± 6.10% of initial weight at the 10-year follow-up (P < 0.001).

CONCLUSIONS

Renal and cardiovascular complications were dramatically reduced in the surgical arm, indicating long-term benefits of BPD on diabetic complications, at least in the case of morbid obesity with decompensated type 2 diabetes.

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.

Chronic increase of bone turnover markers after biliopancreatic diversion is related to secondary hyperparathyroidism and weight loss. Relation with bone mineral density

BACKGROUND

Biliopancreatic diversion (BPD) is the most effective bariatric procedure. Around 70% of these patients have secondary hyperparathyroidism (SH) in the long term as a consequence of calcium and vitamin D malabsorption. This work was aimed to study the influence of SH on bone turnover and its relationship with bone mineral density (BMD).

METHODS

Bone turnover markers were determined in 63 BPD patients and 34 morbidly obese controls. In the BPD group, we also studied the influence of age, loss of weight, common channel length, PTH, vitamin D, and serum calcium on bone turnover as well as its relation with BMD.

RESULTS

BPD patients showed significantly higher PTH, osteocalcin, and beta-CTx levels than controls. In the multivariate regression analysis, only PTH (beta=0.42; P=0.0002), menopausal status (beta=0.31; P=0.007) and the percentage of lost BMI (beta=-0.24; P=0.03) significantly predicted the osteocalcin level (R2=0.33; F=9.56; P<0.0001). Similarly, only PTH (beta=0.39; P=0.0005), menopausal status (beta=0.37; P=0.001) and the percentage of lost BMI (beta=-0.23; P=0.04) significantly predicted the beta-CTx level (R2=0.33; F=9.82; P<0.0001). Osteocalcin and beta-CTx levels correlated negatively with BMD at lumbar spine (r=-0.38, P=0.002 and r=-0.30, P=0.02, respectively).

CONCLUSIONS

Chronic SH and the loss of weight determine a high rate of bone turnover that is associated with decreasing BMD in BPD patients.

Nutritional deficiencies in obesity and after bariatric surgery

The presence of nutritional deficiencies in overweight and obesity may seem paradoxical in light of excess caloric intake, but several micronutrient deficiencies appear to be higher in prevalence in overweight and obese adults and children. Causes are multifactorial and include decreased consumption of fruits and vegetables, increased intake of high-calorie, but nutritionally poor-quality foods, and increased adiposity, which may influence the storage and availability of some nutrients. As the obesity epidemic continues unabated and the popularity of bariatric surgery rises for severely obese adults and adolescents, medical practitioners must be aware of pre-existing nutritional deficiencies in overweight and obese patients and appropriately recognize and treat common and rare nutritional deficiencies that may arise or worsen following bariatric surgery. This article reviews current knowledge of nutritional deficits in obese and overweight individuals and those that commonly present after bariatric surgery and summarizes current recommendations for screening and supplementation.