Prevalence of endocrine disorders in morbidly obese patients and the effects of bariatric surgery on endocrine and metabolic parameters

[Indications and preoperative planning for bariatric surgery]

These clinical practice guidelines represent the consensus opinion of a group of Austrian specialist physicians associated with the treatment of obesity. The recommendations incorporate the current literature and guidelines and aim to balance both procedural feasibility and patient acceptance and adherence. Special emphasis was placed on simplification of the preoperative clarification and maximum patient safety. Therefore, this article makes no claim to be complete in all fields.

Assessment of the diagnostic performance of the 1 mg dexamethasone suppression test in class 3 obese patients

Objective. This study was aimed to evaluate the prevalence of Cushing’s syndrome and the diagnostic performance of the 1 mg dexamethasone suppression test in class 3 obese patients.

Methods. Anthropometric measurements and other laboratory data, including 1 mg dexamethasone suppression test of 753 class 3 obese patients, who applied to the Endocrinology and Metabolism Outpatient Clinic for the pre-bariatric surgery evaluation between 2011 and 2020, were evaluated retrospectively.

Results. An abnormal response to the 1 mg dexamethasone suppression test (cortisol ≥1.8 mcg/dl) was observed in 24 patients and the presence of Cushing’s syndrome was confirmed by additional tests in 6 patients. The prevalence of abnormal dexamethasone suppression test was 3.18% and the prevalence of Cushing’s syndrome 0.79%. The specificity value was determined as 97.5% for 1 mg dexamethasone suppression test with cortisol threshold value ≥1.8 mcg/dl.

Conclusions. The prevalence of Cushing’s syndrome was found to be low in class 3 obese patients and 1 mg of dexamethasone suppression test had a very sufficient performance for Cushing’s syndrome screening in this patient group.

Preoperative preparation and premedication of bariatric surgical patient

The prevalence of obesity has tripled worldwide over the past four decades. The United States has the highest rates of obesity, with 88% of the population being overweight and 36% obese. The UK has the sixth highest prevalence of obesity. The problem of obesity is not isolated to the developed world and has increasingly become an issue in the developing world as well. Obesity carries an increased risk of many serious diseases and health conditions, including type 2 diabetes, heart disease, stroke, sleep apnea, and certain cancers. Our ability to take care of this population safely throughout the perioperative period begins with a thorough and in-depth preoperative assessment and meticulous preparation. The preoperative assessment begins with being able to identify patients who suffer from obesity by using diagnostic criteria and, furthermore, being able to identify patients whose obesity is causing pathologic and physiologic changes. A detailed and thorough anesthesia assessment should be performed, and the anesthesia plan individualized and tailored to the specific patient's risk factors and comorbidities. The important components of the preoperative anesthesia assessment and patient preparation in the patient suffering from obesity include history and physical examination, airway assessment, medical comorbidities evaluation, functional status determination, risk assessment, preoperative testing, current weight loss medication, and review of any prior weight loss surgeries and their implications on the upcoming anesthetic. The preoperative evaluation of this population should occur with sufficient time before the planned operation to allow for modifications of the preoperative management without needing to delay surgery as the perioperative management of patients suffering from obesity presents significant practical and organizational challenges.

The relationship between lipotoxicity and risk of extrathyroidal extension in papillary thyroid microcarcinoma

OBJECTIVE

To explore the relationship between triglyceride (TG) levels and aggressive pathological characteristics in papillary thyroid microcarcinoma (PTMC) patients, especially the relationship between TG, BMI, age, and extrathyroidal extension (ETE).

METHODS

A retrospective analysis of 9663 patients with PTMC in a single center from 2010 to 2017 was included in this study. Binary logistic regression was used to analyze the relationship between serum TG and aggressive pathological characteristics of PTMC in different genders. Further analyzing the risk of high TG in different ages and BMI groups.

RESULTS

Even after adjustment for confounding factors, high TG is still a risk factor for ETE in women with PTMC, but not a risk factor for men. Compared with the group with lower than 0.90 mmol/L, when the TG level is higher than 1.93 mmol/L, the risk of ETE in women increased by about 1.35-fold. The remaining two variables (BMI, age) as risk factors for ETE are analyzed. In the normal BMI group, high TG is still a risk factor for ETE. The risk of ETE in women more than 55 years old is significantly increased by 1.96-fold (1.34-fold in less than 55 years).

CONCLUSION

High TG in women is positively correlated with the risk of ETE in PTMC. PTMC with high TG in elderly women (more than 55 years) has a higher risk of ETE. TG is a potential serological index for predicting the risk of ETE in women with normal BMI.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

Bariatric surgery improves metabolic and nonalcoholic fatty liver disease markers in metabolically healthy patients with morbid obesity at 5 years

BACKGROUND

No studies have evaluated the effect of metabolic and bariatric surgery (MBS) on nonalcoholic fatty liver disease (NAFLD) and cardiometabolic markers in metabolically healthy patients with morbid obesity (MHMO) at midterm.

OBJECTIVES

To assess the effect of MBS on NAFLD and cardiometabolic markers in MHMO patients and ascertain whether metabolically unhealthy patients with morbid obesity (MUMO) remain metabolically healthy at 5 years after MBS.

SETTING

University hospital.

METHODS

A total of 191 patients with a body mass index >40 kg/m² and at least 5 years of follow-up were retrospectively analyzed. Lost to follow-up were 37.6% (151 of 401 patients). Patients were classified as MHMO if 1 or 0 of the cardiometabolic markers were present using the Wildman criteria. The degree of liver fibrosis was assessed using the NAFLD fibrosis score (NFS).

RESULTS

Forty-one patients (21.5%) fulfilled the criteria for MHMO. They showed significant improvements in blood pressure (from 135.1 ± 22.1 and 84.2 ± 14.3 mm Hg to 117.7 ± 19.2 and 73.0 ± 10.9 mm Hg), plasma glucose (from 91.0 ± 5.6 mg/dL to 87.2 ± 5.2 mg/dL), homeostatic model assessment for insulin resistance (from 2.2 ± .9 to 1.0 ± .8), triglycerides (from 88.0 [range, 79.5-103.5] mg/dL to 61.0 [range, 2.0-76.5] mg/dL), alanine aminotransferase, gamma-glutamyl transpeptidase NFS (from -1.0 ± 1.0 to -1.9 ± 1.2), and high-density lipoprotein cholesterol (from 56.9 ± 10.5 mg/dL to 77.9 ± 17.4 mg/dL) at 5 years after surgery. A total of 108 MUMO patients (84.4%) who became metabolically healthy after 1 year stayed healthy at 5 years.

CONCLUSIONS

MBS induced a midterm improvement in cardiometabolic and NAFLD markers in MHMO patients. Seventy-six percent of MUMO patients became metabolically healthy at 5 years after MBS.

Hypercortisolism and altered glucose homeostasis in obese patients in the pre-bariatric surgery assessment

AIMS

Hypothalamus-pituitary-adrenal (HPA) axis hyperactivity was suggested to be associated with the metabolic syndrome (MS), obesity and diabetes. The aim of this study was to test whether hypercortisolism was associated with altered glucose homeostasis and insulin resistance, hypertension and dyslipidemia in a homogeneous population of obese patients.

MATERIALS/METHODS

In retrospective analysis of a set of data about obese patients attending the outpatient service of a single obesity centre between January 2013 and January 2020, 884 patients with BMI >30 kg/m² were segregated in two subgroups: patients with urinary free cortisol (UFC) higher than normal (UFC+; n = 129) or within the normal range (UFC-; n = 755).

RESULTS

The overall prevalence of UFC+ was 14.6% and double test positivity (morning cortisol >1.8 mcg/dL following overnight dexamethasone suppression test, ODST) was detected in 1.0% of patients. Prediabetes (OR 1.74; 95%CI 1.13-2.69; p = 0.012) and diabetes (OR 2.03; 95%CI 1.21-3.42; p = 0.008) were associated with higher risk of UFC+ when analysis was adjusted for confounding variables. Conversely, hypertension and dyslipidemia were not related to UFC+. Within the individuals with normal FPG and HbA1c, those with higher estimated insulin resistance (HOMA2-IR) maintained a higher risk of UFC+ (OR 2.84, 95%CI 1.06-7.63; p = 0.039) and this relationship was weakened only when the body fat percentage was included into the model.

CONCLUSIONS

In obese patients, hypercortisolism was more frequent across the entire spectrum of altered glucose homeostasis including the very early stages; this relation could not be detected for the other criteria of the MS, as waist, hypertension and atherogenic dyslipidemia.

Body mass index (BMI) is associated with serum thyroid-stimulating hormone (TSH) level in infertile women: a cross-sectional study

Studies suggest that there is a relationship between body mass index (BMI) and thyroid-stimulating hormone (TSH) levels. But conflicting evidence exists regarding the relationship between the two variables. Moreover, thyroid function is closely related to female fertility and has certain effects on infertility. Therefore, the present study will explore the relationship between BMI and TSH levels in patients with infertility in our center. We retrospectively analyzed relevant indicators of 2,789 in Tubal Factor Infertility patients undergoing assisted reproduction technology from January 2016 to December 2018 in our center in order to analyze the relationship between BMI and serum TSH level. The medical histories of patients were reviewed. The relationship between BMI and TSH was assessed using smooth curve fitting and multivariate regression model. The smoothing curve fitting between BMI and TSH exhibited a non-linear relationship, and the resulting curve exhibited a two-stage change and a breakpoint. By multivariate piecewise linear regression, we found that the TSH level was increased with the increase of BMI when the BMI was greater than 25.3 kg/m² (β 0.06, 95% CI 0.02, 0.01; p = 0.0028). In contrast, the TSH level was decreased with the increase of BMI when the BMI was less than 25.3 kg/m² (β -0.02, 95% CI -0.05, 0.00; p = 0.0573). Collectively, our study described a non-linear relationship between BMI and TSH level in infertile patients after adjustment of potential confounders. However, such causal relationship between BMI and TSH in infertile women still needs to be further clarified in future investigations.

Assessment of 1 mg Dexamethasone Suppression Test in Patients with Obesity Before Bariatric Surgery

PURPOSE

This study aims to examine the prevalence of Cushing's syndrome (CS) in class 3 obese patients before bariatric surgery.

MATERIALS AND METHODS

The data of 1037 class 3 obese patients admitted to the endocrinology outpatient clinic for endocrinological evaluation before bariatric surgery between 2012 and 2019were reviewed retrospectively. One milligram dexamethasone suppression test (DST) was used for the evaluation of hypercortisolism in all cases and cutoff accepted as 1.8 μg/dL.

RESULTS

The mean body mass index (BMI) was 48 ± 8.9 kg/m² and age was 42 ± 10 years with female preponderance (F/M: 799/238] being observed in this cohort. Insufficient cortisol suppression was found in 40 patients; confirmed hypercortisolemia was detected in 8 patients. The prevalence of pathologic DST was 3.85% and 0.77% in confirmed hypercortisolism. The specificity for 1-mg DST with the cutoff 1.8 μg/dL was calculated as 96.8%.

CONCLUSION

Hypercortisolism prevalence was found to be low, and 1 mg DST is a sufficient test for the screening of CS in class 3 obese patients evaluated before bariatric surgery.

Thyroid Hormone Changes After Sleeve Gastrectomy With and Without Antral Preservation

BACKGROUND

The effect of bariatric surgery on thyroid hormone changes yielded inconsistent results. The aim of the present study was to assess the change of thyroid hormone levels following laparoscopic sleeve gastrectomy (LSG), with or without antral preservation (AP).

METHODS

Thyroid hormones (TSH, FT3, FT4) were examined preoperatively, at the end of the first postoperative month, and first postoperative year. Secondly, antral resection (AR) and AP were compared at inducing weight loss and thereby affecting thyroid hormone levels.

RESULTS

Euthyroid obese patients (86 female/20 male) underwent LSG. Of these, 58 patients underwent AR and 48 patients AP. The mean FT3 levels significantly decreased both in the first postoperative month and the first year (P < 0.001), whereas mean TSH levels decreased significantly in the first postoperative year (P < 0.001). FT4 levels remained nearly unchanged (P = 0.517). Postoperative first year body mass index (BMI) loss, excess BMI loss percentile (%EBMIL), and total body weight loss percentile (%TWL) were significantly higher in AR group than the AP group (P ≤ 0.01). When the change in thyroid hormone levels was analyzed by pyloric distance according to time periods, no significant difference was found in TSH and FT4 levels (P > 0.05); however, reduction in FT3 levels was significantly greater in patients with AR than in AP patients (P = 0.028).

CONCLUSION

LSG promotes significant reduction in TSH and FT3 levels, whereas FT4 levels remain unchanged. LSG with AR provides more weight loss in short term and appears to be more effective at lowering FT3 levels.

Perioperative care of the obese patient

Background

Obesity has become an increasing problem worldwide during the past few decades. Hence, surgeons and anaesthetists will care for an increasing number of obese patients in the foreseeable future, and should be prepared to provide optimal management for these individuals. This review provides an update of recent evidence regarding perioperative strategies for obese patients.

Methods

A search for papers on the perioperative care of obese patients (English language only) was performed in July 2019 using the PubMed, Scopus, Web of Science and Cochrane Library electronic databases. The review focused on the results of RCTs, although observational studies, meta-analyses, reviews, guidelines and other reports discussing the perioperative care of obese patients were also considered. When data from obese patients were not available, relevant data from non-obese populations were used.

Results and conclusion

Obese patients require comprehensive preoperative evaluation. Experienced medical teams, appropriate equipment and monitoring, careful anaesthetic management, and an adequate perioperative ventilation strategy may improve postoperative outcomes. Additional perioperative precautions are necessary in patients with severe morbid obesity, metabolic syndrome, untreated or severe obstructive sleep apnoea syndrome, or obesity hypoventilation syndrome; patients receiving home ventilatory support or postoperative opioid therapy; and obese patients undergoing open operations, long procedures or revisional surgery.

Thyroid function before and after Roux-en-Y gastric bypass: an observational study

BACKGROUND

Population studies have shown a positive association between thyroid-stimulating hormone (TSH) and body mass index. Recent studies have shown a significant increase in the prevalence of subclinical hypothyroidism (SCH) in obesity. Weight reduction after Roux-en-Y gastric bypass (RYGB) seems to significantly decrease TSH levels.

OBJECTIVES

The purpose of this study was to evaluate the prevalence of SCH in obese patients (class II and III) and to observe the behavior of thyroid hormones (TSH, hormone triiodothyronine, thyroxine, free thyroxine) with significant weight loss after RYGB.

SETTING

Hospital Nossa Senhora das Graças, Curitiba, Paraná, Brazil.

METHODS

We retrospectively reviewed the medical records of 215 obese patients who underwent RYGB between 2005 and 2012 with a follow-up of at least 2 years. The study was observational and descriptive. The selected times for clinical and laboratory evaluations were preoperative, 3, 6, 12, and 24 months after the procedure. Association, correlation, and variance analyses were performed.

RESULTS

The prevalence of SCH preoperatively was 9.3%. SCH was corrected in 89.5% of patients 12 months after RYGB. We did not find an association between TSH and BMI (r = .002, P = .971). There was a positive impact of bariatric surgery on all metabolic variables. We showed that serum TSH level had no positive correlation with the presence or absence of metabolic syndrome.

CONCLUSIONS

Weight loss after bariatric surgery leads to normalization of TSH levels in most patients and none developed overt hypothyroidism. Obese patients with SCH should not be treated with thyroid hormone replacement. Serial monitoring of thyroid function after obesity therapy seems to be a reasonable approach.

The Effect of the Bariatric Surgery Type on the Levothyroxine Dose of Morbidly Obese Hypothyroid Patients

BACKGROUND

Doubts exist about the effect of different bariatric surgery (BS) types on levothyroxine (Lt4) absorption. We compared Lt4 doses and their variation (ΔLt4) in patients with hypothyroidism that underwent malabsorptive (MS) or restrictive (RS) surgery and studied predictors of Lt4 dose change.

METHODS

Retrospective study of morbidly obese hypothyroid patients submitted to BS. We compared RS ("sleeve" gastrectomy or adjustable gastric banding) with MS (Roux-en-Y gastric bypass) patients. We built a multivariable logistic regression and a linear regression model to study predictors of Lt4 dose changes and ΔLt4, respectively.

RESULTS

Fifty-seven patients: 35 MS and 22 RS. Mean age 47 years; 7% men. Patients submitted to MS had lower BMI at 1 year than those submitted to RS. Lt4 dose remained unchanged in 61.4%, increased in 12.3%, and decreased in 26.3% of patients. Initial and 1-year Lt4 dose were not different between surgical groups. Relative Lt4 dose, but not absolute (p = 0.07), increased at 1 year (p < 0.001). Neither BS nor BMI variation were predictors of Lt4 dose variation. BMI variation was associated with relative Lt4 dose change independently of initial BMI and BS type: β (95%CI) - 0.03 (- 0.05; 0.00); p = 0.03.

CONCLUSIONS

There were no differences in Lt4 dose and its variation between restrictive and malabsorptive techniques 1 year after surgery. Malabsorptive procedures may not affect Lt4 absorption differently from restrictive ones. Bariatric surgery type was not predictive of Lt4 dose changes. BMI variation is associated with relative Lt4 dose (dose per weight) variation and its association was independent of bariatric surgery type.

Effect of Weight Loss after Bariatric Surgery on Thyroid-Stimulating Hormone Levels in Patients with Morbid Obesity and Normal Thyroid Function

BACKGROUND

Several studies have reported that morbid obesity is associated with increased thyroid-stimulating hormone (TSH) levels. However, it is not clear what is the impact of bariatric surgery on postoperative thyroid function. The aim of this study was to evaluate the effect of weight loss after bariatric surgery on TSH levels in euthyroid patients with morbid obesity.

METHODS

We performed a retrospective observational study of 949 euthyroid patients (86.1% female; age 42.0 ± 10.3 years, BMI 44.3 ± 5.7 kg/m²) with morbid obesity submitted to bariatric surgery (laparoscopic adjustable gastric band, Roux-en-Y gastric bypass, or sleeve gastrectomy). Patients were subdivided in two groups: normal TSH group (TSH <2.5 mU/L) and high-normal TSH group (TSH ≥2.5 mU/L). The impact of anthropometric parameters, comorbidities, TSH, free thyroxine (FT4), free triiodothyronine (FT3), type of surgery, and excessive body weight loss (EBWL) on TSH variation 12 months after surgery was evaluated.

RESULTS

The high-normal TSH group (24.3% of patients) included more women, presented a higher BMI, higher systolic blood pressure, and higher FT3 levels. There was a significant decrease of TSH 12 months after surgery that was more marked in the high-normal TSH group (normal TSH group: 1.57 ± 0.49 to 1.53 ± 0.69 mIU/L, p = 0.063; high-normal TSH group: 3.23 ± 0.59 to 2.38 ± 0.86 mIU/L, p < 0.001). In a multivariate analysis, after adjusting for relevant covariates, EBWL, baseline BMI, and baseline FT3 were significantly associated with TSH decrease 12 months after bariatric surgery.

CONCLUSION

Bariatric surgery promotes a decrease of TSH that is significantly greater in patients with high-normal TSH and is independently associated with EBWL after surgery.

Preoperative thyroid function and weight loss after bariatric surgery

Thyroid function has an important role on body weight regulation. However, the impact of thyroid function on weight loss after bariatric surgery is still largely unknown. We evaluated the association between preoperative thyroid function and the excess weight loss 1 year after surgery, in 641 patients with morbid obesity who underwent bariatric surgery. Patients with a history of thyroid disease, treatment with thyroid hormone or antithyroid drugs and those with preoperative evaluation consistent with overt hypothyroidism or hyperthyroidism were excluded. The preoperative levels of TSH and FT4 were not associated with weight loss after bariatric surgery. The variation of FT3 within the reference range was also not associated with weight loss. In contrast, the subgroup with FT3 above the reference range (12.3% of patients) had a significantly higher excess weight loss than patients with normal FT3. This difference remained significant after adjustment for age, sex, BMI, type of surgery, TSH and FT4. In conclusion, we observed an association between high FT3 and a greater weight loss after bariatric surgery, highlighting a group of patients with an increased benefit from this intervention. Our results also suggest a novel hypothesis: the pharmacological modulation of thyroid function may be a potential therapeutic target in patients undergoing bariatric surgery.

Effect of Bariatric Surgery on Thyroid Function in Obese Patients: a Systematic Review and Meta-Analysis

We aimed to make a meta-analysis regarding the effect of bariatric surgery on thyroid function in obese patients. PubMed, EMBASE, CENTRAL, and four Chinese databases were searched for clinical studies. Data were pooled using Review Manager 5.3, and subgroup and sensitivity analyses were performed if necessary and feasible. As a result, 24 articles were included into meta-analysis. Bariatric surgery was associated with significant decrease in TSH, FT3, and T3 levels. However, FT4, T4, and rT3 levels were not significantly changed postoperatively. In addition, bariatric surgery had a favorable effect on overt and subclinical hypothyroid, with reduction of thyroid hormone requirements postoperatively. In conclusion, TSH, FT3, and T3 decrease are expected following bariatric surgery, as well as non-significant change of T4, FT4, and rT3 levels.

Incidence of Cushing's syndrome in patients with significant hypercortisoluria

OBJECTIVE

To investigate the incidence of Cushing's syndrome (CS) in patients with significant hypercortisoluria and the performance of urinary free cortisol (UFC) screening.

DESIGN

Retrospective file review.

METHODS

The computerized database of a publicly funded health maintenance organization (HMO) in Israel was searched for all patients who underwent 24-h UFC testing in 2005-2014 with a result of more than twice the upper limit of normal (ULN). The patients' medical files were reviewed for a subsequent diagnosis of CS by an expert endocrinologist. Findings were evaluated for patterns in CS diagnosis and UFC testing over time.

RESULTS

Of 41 183 individuals tested, 510 (1.2%) had UFC >2× ULN (214 >3× ULN). Eighty-five (16.7%) individuals were diagnosed with CS (63 female and mean age 47.2 ± 15.1 years), mainly Cushing's disease (55.3%) or adrenal Cushing's syndrome (37.6%). The number of UFC tests increased steadily, from 1804 in 2005 to 6464 in 2014; yet, the resultant detection rate of CS remained generally stable. The calculated incidence of CS in the general HMO-insured population based only on the patients identified in the present cohort was 4.5 new cases/million/year (median 4.9/million/year, range 1.7-5.9/million/year), which was also relatively stable. The most common reason for referral for UFC screening was obesity. Of the 148 patients before bariatric surgery with UFC >2× ULN, 2 were diagnosed with CS.

CONCLUSIONS

The incidence of CS is higher than previously suggested. The consistently increasing number of UFC tests being performed has not been accompanied by a similar increase in CS detection rate. The expected yield of routine UFC testing before bariatric surgery is low.

[Incretin secretion and glucose metabolism in morbidly obese patients in the early and late periods after biliopancreatic diversion]

AIM

To estimate the parameters of glucose metabolism and to assess the secretion of incretins in patients after biliopancreatic diversion (BPD) for morbid obesity (MO) in the early and late postoperative periods.

SUBJECTS AND METHODS

The prospective part of the investigation included 22 patients with a body mass index of 35.8 to 68.4 kg/m2 and type 2 diabetes mellitus (T2DM). All the patients were examined before, 3 weeks and 3 months after BPD. The retrospective part covered 23 patients who were examined after BPD for MO; the postoperative period was 4.7 [2.3; 7.2] years. A control group consisted of 22 healthy, normal weight volunteers. A 75-g oral glucose tolerance test was carried out in all the groups to study the levels of glucose, immunoreactive insulin (IRI), glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and glucagon at 0, 30, 60, and 120 min.

RESULTS

T2DM patients showed improvement in glucose metabolism just 3 weeks after BPD; following 3 months, they had normalized fasting blood glucose levels (5.6 [5.0; 6.0] mmol/l). During 3 months, glycated hemoglobin decreased from 7.5 [6.6; 8.5] to 5.7 [5.3; 5.9]%. In the early period following BPD, there was an increase in basal and postprandial GLP-1 levels associated with the peak IRI concentration. In the late period after BPD, the enhanced secretion of IRI and GLP-1 persisted, which was followed by a reduction in postprandial glucose levels in 4 of the 23 patients.

CONCLUSION

T2DM remission does not depend on weight loss in the early period after BPD. In this period, the significant improvement of glucose metabolic parameters in patients with obesity and T2DM is associated with elevated GLP-1 levels. The altered incretin response is a stable effect of BPD and remains in its late period.

Performance of the 1 mg dexamethasone suppression test in patients with severe obesity

OBJECTIVE

To analyze the performance of the 1 mg dexamethasone suppression test (DST) in patients with obesity. Special attention was paid to the influence of interfering medication on DST.

METHODS

In this prospective cohort study (Mannheim Obesity Study), patients with obesity were evaluated before bariatric surgery. For evaluation of hypercortisolism, a 1 mg dexamethasone-suppression test (DST) in all subjects was performed. Medication was assessed for possible interference.

RESULTS

Two hundred seventy-eight patients with a mean age of 42.3 years (68.8% women) and a mean BMI of 47.9 ± 8.4 kg/m(2) were screened. Insufficient suppression of cortisol after DST was found in 24 patients (8.6%). In two patients hypercortisolism was confirmed. The specificity for DST was calculated at 92.0%. Only CYP3A4 inducers (n = 22, 7.9%) and estrogen therapy (n = 17, 6.1%) were significantly associated with falsely elevated cortisol after DST. Regression analysis excluded any interrelation between DST and anthropometry.

CONCLUSIONS

Low prevalence of hypercortisolism (0.7 or <1.8%) was found. Specificity of DST in this cohort typically screened for hypercortisolism was 92.0% (≤ 50 nmol/L). DST should be avoided in patients taking CYP3A4 inducers or estrogen therapy, due to their significant interaction. In summary, the 1 mg DST is an adequate test for screening for hypercortisolism even in patients with extreme obesity.

Lipotoxicity, a potential risk factor for the increasing prevalence of subclinical hypothyroidism?

CONTEXT

Subclinical hypothyroidism (SCH) is an important public health problem worldwide for its increasing prevalence and potential deleterious effects, whereas its etiology has not been fully elucidated. Lipotoxicity exerts extensive and serious impact on human health, but so far, the potential effect of lipotoxicity on thyroid is unclear.

OBJECTIVE

The objective of the study was to assess the association between serum triglyceride levels and the risk for SCH.

DESIGN, PARTICIPANTS, AND METHODS

We conducted a population-based case-control study. A total of 24 100 subjects with similar and stable iodine nutrition status were recruited from China. Cases of 5033 SCH patients were identified and equal controls were matched by age, gender, and region. Conditional logistic regression was used to analyze the association between serum triglyceride levels and risk for SCH.

RESULTS

Hypertriglyceridemia was associated with an approximately 35% increased risk for SCH in both men (odds ratio 1.325; 95% confidence interval 1.002-1.753) and women (odds ratio 1.397; 95% confidence interval 1.217-1.604), even after adjustment for potential confounders. Notably, the risk for SCH increased progressively following the elevation of serum triglyceride levels. Compared with individuals with serum triglyceride levels less than 0.97 mmol/L, the risk for SCH increased approximately 1.9-fold in men and 1.4-fold in women, respectively, when triglyceride levels were greater than 1.99 mmol/L.

CONCLUSION

Our findings suggested that hypertriglyceridemia was positively associated with the risk for SCH.

Screening for Cushing's syndrome: is it worthwhile?

INTRODUCTION

Cushing's syndrome (CS) is a rare disease characterized by a collection of signs and symptoms, also common in the general population without elevated cortisol secretion. During the last years more patients with CS are identified earlier and with milder disease. Many of these patients are diagnosed during screening efforts performed for certain or isolated complaints like weight gain, diabetes mellitus (DM), hypertension, osteoporosis, elevated white blood cell counts and more.

METHODS

In this review article the most popular screening test performed in the studies cited was the 1-mg dexamethasone suppression test.

CONCLUSIONS

Cushing is not frequent enough to support the use of routine screening in patients with morbid obesity and type 2 DM. Also only 1% of hypertensive patients have secondary hypertension due to CS. However, screening should be considered in young patients with resistant DM and/or hypertension. Among patients with osteoporosis and vertebral fractures up to 5% were diagnosed with subclinical hypercortisolism; most of these had adrenal adenoma. Screening for CS is important in subjects with adrenal incidentaloma, and many studies show a high prevalence (~10%) of Cushing or subclinical CS in these patients.

Cushing's syndrome in a morbidly obese patient undergoing evaluation before bariatric surgery

OBJECTIVE

Cushing's syndrome (CS) is extremely rare in morbidly obese patients. To date, no occurrences in obese patients with BMI above 60 kg/m2 have been reported in the literature.

CASE REPORT

This case report describes a patient who was admitted to the ward of the Clinical Division of Endocrinology and Metabolism of the Medical University of Vienna in preparation for bariatric surgery. The patient was a 49-year-old female who showed morbid obesity (BMI 61.6 kg/m2), hypertension, and substituted hypothyroidism. Preoperative work-up revealed CS due to an adrenal adenoma. Therefore, the patient underwent unilateral adrenalectomy followed by bariatric surgery 6 months later.

CONCLUSION

Since undiagnosed CS might result in severe perioperative complications in a population already at increased risk, this case report underlines the importance of careful endocrine evaluation of morbidly obese patients. After all, even rare endocrine causes should be excluded.

Laparoscopic sleeve gastrectomy for morbid obesity and glucose metabolism: a new perspective

BACKGROUND

Global rise in the incidence of obesity and type 2 diabetes mellitus is widely recognized as one of the most challenging contemporary threats to public health. Weight loss surgery has proven to be an effective and durable solution for morbidly obese adults. Laparoscopic sleeve gastrectomy (LSG) was introduced as a restrictive procedure for obese patients, initially described as a possible first-stage operation, but now commonly performed as a stand-alone bariatric operation for both high-risk and super-morbid-obese patients, as well as for patients with lower body mass index. This study aims to evaluate the progression of glucose metabolism in patients undergoing LSG.

METHODS

This prospective study investigated 62 patients who underwent LSG by the same surgical team in an 18-month period. Preoperative evaluation included demographic information, complete medical history including comorbidities and medication, clinical examination, evaluation of cardiopulmonary function, measurement of weight and height on a standard electronic scale, upper gastrointestinal endoscopy and upper abdominal ultrasound, as well as interviews with a psychologist and nutritionist. Glucose metabolism was evaluated by oral glucose tolerance test (OGTT), preoperatively and at 3, 6, and 12 months after surgery.

RESULTS

The OGTT was significantly ameliorated in all groups during follow-up. Nine of 12 diabetic patients (75 %) ceased drug treatment at 3 months postoperatively (p = 0.004), increasing to 100 % at 1-year follow-up (p < 0.001). Normoglycemic patients and patients with borderline OGTT experienced mild or severe hypoglycemia during the glucose tolerance test at 3, 6, and 12 months' follow-up.

CONCLUSIONS

LSG offers excellent results to morbidly obese patients with regard to type 2 diabetes mellitus. Implementation of OGTT in these patients can be a valuable tool in their postoperative management. Bariatric teams performing LSG for morbid obesity should heighten their sensitivity to postoperative hypoglycemia, even in patients with type 2 diabetes mellitus.

Routine Screening for Cushing's Syndrome Is Not Required in Patients Presenting with Obesity

Background. Cushing's syndrome (CS) is a relatively unusual condition that resembles many of the phenotypic features of obesity. Our aim was to evaluate the frequency of CS in obese patients. Materials and Methods. This study included 354 consecutive patients (87.9% female, age 37.8 ± 13.4 years) who presented with simple obesity. All the patients were evaluated for the clinical signs of CS. Lipid parameters, fasting glucose (FPG) and insulin, 75 gr oral glucose tolerance test, basal cortisol and ACTH were measured. 1 mg overnight DST was performed. Results. The mean weight of the patients was 102.4 ± 20.1 kg and BMI 40 ± 7.35 kg/m². 34.5% of the patients were hypertensive. 36.2% of the patients had central obesity, 72% dorsocervical fat accumulation, 28.8% abdominal striae and 23.2% acne. 49.4% of the women had hirsutism. 46.5% had prediabetes and 12.0% had type 2 diabetes, 72.6% had dyslipidemia. The mean cortisol and ACTH levels were as follows: 9.28 ± 3.53 μg/dL and 17.02 ± 10.43 pg/mL. Seven patients failed to suppress plasma cortisol to less than 1.8 μg/dL. Biochemical confirmation tests were performed in these patients and 2 of them were diagnosed glucocorticoid-secreting adrenal adenoma. Conclusions. Routine screening for CS in obese patients is not required.

Endocrine changes (beyond diabetes) after bariatric surgery in adult life

Bariatric surgery is nowadays an effective therapeutic option for morbid obesity. Endocrinologists may thus have a growing opportunity to diagnose and treat obese patients eligible for surgery in pre- and post-operative phase. This requires a better understanding of endocrine changes caused by either obesity or weight loss surgery. Despite the large number of studies available in literature, only limited well-designed clinical trials have been performed so far to investigate changes of endocrine axes following bariatric procedures. There are still areas of unclear results such as female and male fertility, however, weight loss after bariatric surgery is considered to be associated with favorable effects on most endocrine axes. The aim of this clinical review is to overview the available literature on the effects of weight loss after bariatric surgery on the endocrine systems to suggest the most appropriate pre- and post-operative management of obese patients undergoing bariatric surgery in terms of "endocrine" health.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Routine screening for Cushing's syndrome is not required in patients presenting with hirsutism

CONTEXT

Prevalence of Cushing's syndrome (CS) in patients presenting with hirsutism is not well known.

OBJECTIVE

Screening of CS in patients with hirsutism.

SETTING

Referral hospital.

PATIENTS AND OTHER PARTICIPANTS

This study was carried out on 105 patients who were admitted to the Endocrinology Department with the complaint of hirsutism.

INTERVENTION

All the patients were evaluated with low-dose dexamethasone suppression test (LDDST) for CS.

MAIN OUTCOME MEASURE

Response to LDDST in patients presenting with hirsutism.

RESULTS

All the patients had suppressed cortisol levels following low-dose dexamethasone administration excluding CS. The etiology of hirsutism was polycystic ovary syndrome in 79%, idiopathic hirsutism in 13%, idiopathic hyperandrogenemia in 6%, and nonclassical congenital hyperplasia in 2% of the patients.

CONCLUSION

Routine screening for CS in patients with a referral diagnosis of hirsutism is not required. For the time being, diagnostic tests for CS in hirsute patients should be limited to patients who have accompanying clinical stigmata of hypercortisolism.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Alterations in gastrointestinal, endocrine, and metabolic processes after bariatric Roux-en-Y gastric bypass surgery

OBJECTIVE

Obesity leads to severe long-term complications and reduced life expectancy. Roux-en-Y gastric bypass (RYGB) surgery induces excessive and continuous weight loss in (morbid) obesity, although it causes several abnormal anatomical and physiological conditions.

RESEARCH DESIGN AND METHODS

To distinctively unveil effects of RYGB surgery on β-cell function and glucose turnover in skeletal muscle, liver, and gut, nondiabetic, morbidly obese patients were studied before (pre-OP, five female/one male, BMI: 49 ± 3 kg/m(2), 43 ± 2 years of age) and 7 ± 1 months after (post-OP, BMI: 37 ± 3 kg/m(2)) RYGB surgery, compared with matching obese (CON(ob), five female/one male, BMI: 34 ± 1 kg/m(2), 48 ± 3 years of age) and lean controls (CON(lean), five female/one male, BMI: 22 ± 0 kg/m(2), 42 ± 2 years of age). Oral glucose tolerance tests (OGTTs), hyperinsulinemic-isoglycemic clamp tests, and mechanistic mathematical modeling allowed determination of whole-body insulin sensitivity (M/I), OGTT and clamp test β-cell function, and gastrointestinal glucose absorption.

RESULTS

Post-OP lost (P < 0.0001) 35 ± 3 kg body weight. M/I increased after RYGB, becoming comparable to CON(ob), but remaining markedly lower than CON(lean) (P < 0.05). M/I tightly correlated (τ = -0.611, P < 0.0001) with fat mass. During OGTT, post-OP showed ≥15% reduced plasma glucose from 120 to 180 min (≤4.5 mmol/L), and 29-fold elevated active glucagon-like peptide-1 (GLP-1) dynamic areas under the curve, which tightly correlated (r = 0.837, P < 0.001) with 84% increased β-cell secretion. Insulinogenic index (0-30 min) in post-OP was ≥29% greater (P < 0.04). At fasting, post-OP showed approximately halved insulin secretion (P < 0.05 vs. pre-OP). Insulin-stimulated insulin secretion in post-OP was 52% higher than before surgery, but 1-2 pmol/min(2) lower than in CON(ob)/CON(lean) (P < 0.05). Gastrointestinal glucose absorption was comparable in pre-OP and post-OP, but 9-26% lower from 40 to 90 min in post-OP than in CON(ob)/CON(lean) (P < 0.04).

CONCLUSIONS

RYGB surgery leads to decreased plasma glucose concentrations in the third OGTT hour and exaggerated β-cell function, for which increased GLP-1 release seems responsible, whereas gastrointestinal glucose absorption remains unchanged but lower than in matching controls.