Modification of Endotypic Traits in OSA by the Carbonic Anhydrase Inhibitor Sulthiame

BACKGROUND

The carbonic anhydrase inhibitor sulthiame reduces OSA severity, increases overnight oxygenation, and improves sleep quality. Insights into how sulthiame modulates OSA pathophysiologic features (endotypic traits) adds to our understanding of the breathing disorder itself, as well as the effects of carbonic anhydrases in respiratory regulation.

RESEARCH QUESTION

How does sulthiame treatment modify endotypic traits in OSA?

STUDY DESIGN AND METHODS

Per-protocol tertiary analysis of a randomized controlled trial with the inclusion criteria as follow: BMI, ≥ 20 to ≤ 35 kg/m2; age, 18-75 years; apnea-hypopnea index (AHI) ≥ 15 events/h; Epworth sleepiness scale score, ≥ 6; as well as nonacceptance or nontolerance of positive airway pressure treatment. Patients were randomized to receive placebo (n = 22), sulthiame 200 mg (n = 12), or sulthiame 400 mg (n = 24) during 4 weeks of treatment. Polysomnography was applied twice at baseline and follow-up. Endotypic traits were determined from polysomnography tracings (PUPBeta). Sulthiame plasma concentration was analyzed. Differences from baseline to follow-up (Δs) were analyzed with the analysis of covariance or Kruskal-Wallis H test and Pearson (r) or Spearman correlations (rs).

RESULTS

Sulthiame (200-mg and 400-mg groups) consistently reduced loop gain (response to a 1-cycle/min disturbance, LG1; mean, -0.16 [95% CI, -0.18 to -0.13]; P < .05) in addition to increased ventilation at lowest decile of ventilatory drive (Vmin; median, +12 [95% CI, 4-20]; P < .05) and median ventilation at eupneic ventilatory drive (Vpassive; median, +4 [95% CI, 0-5]; P < .05). ΔLG1 correlated with ΔAHI percentage (200 mg: r = 0.65; P < .05). Vmin and Vpassive correlated with ΔAHI (all sulthiame: rs = -0.59 and rs = -0.65; P < .05 for all). The reduction of LG1 was seen already in the lower sulthiame concentration range, whereas changes in Vmin peaked in the higher range.

INTERPRETATION

The effect of sulthiame in OSA may be explained by a reduction of ventilatory instability (LG1) as well as upper airway collapsibility (Vmin and Vpassive).

TRIAL REGISTRY

European Union Drug Regulating Authorities Clinical Trials Database; No.: EudraCT 2017-004767-13; URL: https://www.clinicaltrialsregister.eu.

The placebo effect in pharmacological treatment of obstructive sleep apnea, a systematic review and meta-analysis

OBJECTIVE

New drug treatments are under development in obstructive sleep apnea (OSA). The placebo effect is well recognized in various conditions, but its relevance in OSA is debated. In the current study we determined the influence of a placebo effect in studies of drug therapy in OSA.

METHODS

A systematic review and meta-analysis (PROSPERO CRD42021229410) with searches in MEDLINE, Scopus, Web of Science and Cochrane CENTRAL from inception to 2021-01-19. Inclusion criteria were (i) RCTs of adults with OSA, (ii) drug intervention with placebo baseline and follow-up sleep study (iii) outcomes: apnea hypopnea index (AHI), mean oxygen saturation (mSaO2), oxygen desaturation index (ODI) and/or Epworth Sleepiness Scale (ESS). Risk-of-bias was assessed with Cochrane RoB 2.

RESULTS

7436 articles were identified and 29 studies included (n = 413). Studies were generally small (median n = 14), with 78% men, baseline AHI range 9-74 events/h and treatment duration range 1-120 days. Meta-analyses were conducted for main outcomes. Mean change of the primary outcome, AHI, was -0.84 (95% CI -2.98 to 1.30); mSaO2 and ODI estimations were also non-significant. ESS showed a trend towards a reduction of -1 unit. Subgroup analysis did not show significant differences. Risk-of-bias assessment indicated mostly low risk but studies were small with wide confidence intervals.

CONCLUSIONS

In this meta-analysis we did not identify systematic placebo effects on the AHI, ODI or mSaO2 while ESS score showed a trend for a small reduction. These results have an impact on the design and interpretation of drug trials in OSA.

A Randomized Controlled Trial Exploring Safety and Tolerability of Sulthiame in Sleep Apnea

RATIONAL

Current therapies in obstructive sleep apnea (OSA) are limited by insufficient efficacy, compliance or tolerability. An effective pharmacological treatment in OSA is warranted. Carbonic anhydrase (CA) inhibition has been shown to ameliorate OSA.

OBJECTIVE

To explore safety and tolerability of the CA inhibitor sulthiame (STM) in OSA.

METHODS

A four week double-blind, randomized, placebo-controlled dose guiding trial in patients with moderate/severe OSA not tolerating positive airway pressure treatment.

MEASUREMENTS AND RESULTS

Intermittent paresthesia was reported by 79, 67 and 18% of patients receiving 400 mg STM (N=34), 200 mg STM (N=12) or placebo (N=22), respectively. Dyspnea was reported only after 400 mg STM (18%). Six patients in the higher dose group withdrew due to an adverse event. There were no serious adverse events. STM reduced the apnea-hypopnea index (AHI) from 55.3 to 33.1 events/h ( 41.0%) in the 400 mg group and from 61.2 to 40.7 events/h ( 32.1%) after 200 mg (p<0.001, respectively). Corresponding placebo values were 53.9 and 50.9 events/h ( 5.4 %). The AHI reduction threshold of ≥50% was reached in 40% after 400 mg, 25% after 200 mg and 5% following placebo. Mean overnight oxygen saturation improved by 1.1% after 400 mg and 200 mg (p<0.001 and p=0.034, respectively). Patient related outcomes were unchanged.

CONCLUSIONS

STM showed a satisfactory safety profile in moderate/severe OSA. STM reduced OSA by more than 20 events/h, one of the strongest reductions reported in a drug trial in OSA. Larger scale clinical studies of STM in OSA are justified. Clinical trial registration available at https://www.clinicaltrialsregister.eu/https://www.clinicaltrialsregister.eu/, ID: 2017-004767-13.

Biliopancreatic Diversion is associated with greater increases in energy expenditure than Roux-en-Y Gastric Bypass

Objective

The greater weight loss achieved following Biliopancreatic Diversion with Duodenal Switch (BPDS) versus Roux-en-Y Gastric Bypass (RYGB) has been attributed to the malabsorptive effects of BPDS. Increased weight loss after BPDS could also be underpinned by larger increases in energy expenditure. Hypothetically, the more radical reconfiguration of the small intestine in BPDS could result in an accentuated increase in meal associated thermogenesis (MAT).

Design

Female subjects (baseline mean age 40 years, mean BMI-55kg/m²) were assessed four years after randomization to BPDS (n = 6) or RYGB (n = 6). Energy expenditure (EE) and respiratory quotient (RQ) were measured by indirect calorimetry over 24 hours. A detailed protocol allowed for discrimination of basal metabolic rate (BMR), fasting EE and MAT as components of total energy expenditure (TEE) normalised for total and lean tissue by dual-energy x-ray absorptiometry.

Results

Median weight loss at follow-up was 1.5-fold higher following BPDS relative to RYGB, resulting in respective median BMIs of 29.5 kg/m² (21.7 to 36.7) after BPDS and 37.8 kg/m² (34.1 to 45.7) after RYGB (p = 0.015). The BPDS group had a lower fat:lean ratio compared to the RYGB group (p = 0.009). Overall 24-hour TEE adjusted for total tissue was higher in the BPDS group, as were BMR, fasting EE and MAT (all p<0.05). Differences between RYGB and BPDS in BMR and TEE were nullified when normalised for lean mass. Postprandial RQ increased significantly but to a similar extent in both groups.

Conclusion

Enhanced and prolonged MAT and lower fat:lean mass ratios after BPDS may explain relative increases in total energy expenditure as compared to RYGB.

Long-term QALY-weights among spouses of dependent and independent midlife stroke survivors

Purpose

The aim of this study was to investigate whether the dependency of midlife stroke survivors had any long-term impact on their spouses’ QALY-weights.

Method

Data on stroke survivors, controls, and spouses were collected from the 7-year follow-up of the Sahlgrenska Academy Study on Ischemic Stroke. Health-related quality of life was assessed by the SF-36, and the preference-based health state values were assessed with the SF-6D. Spouses of dependent and independent stroke survivors were categorized according to their scores on the modified Rankin Scale. An ordinary least squares regression analysis was used to evaluate whether the dependency of the stroke survivors had any impact on the spouses’ QALY-weights.

Result

Cohabitant dyads of 247 stroke survivors aged <70 at stroke onset and 245 dyads of controls were included in the study. Spouses of dependent stroke survivors (n = 50) reported a significant lower mean QALY-weight of 0.69 in comparison to spouses of independent stroke survivors (n = 197) and spouses of controls, (n = 245) who both reported a mean QALY-weight of 0.77. The results from the regression analysis showed that higher age of the spouse and dependency of the stroke survivor had a negative association with the spouses’ QALY-weights.

Conclusion

The QALY-weights for spouses of dependent midlife stroke survivors were significantly reduced compared to spouses of independent midlife stroke survivors. This indicates that the inclusion of spouses’ QALYs in evaluations of early treatment and rehabilitation efforts to reduce stroke patients’ dependency would capture more of the total effect in dyads of stroke survivors.

Effects of canagliflozin on body weight and relationship to HbA1c and blood pressure changes in patients with type 2 diabetes

AIMS/HYPOTHESIS

Canagliflozin, a sodium glucose co-transporter 2 inhibitor, reduces HbA1c, body weight and systolic BP (SBP) in patients with type 2 diabetes. As weight loss is known to reduce both HbA1c and SBP, these analyses were performed to evaluate the contribution of weight loss resulting from treatment with canagliflozin to HbA1c and SBP reductions in patients with type 2 diabetes.

METHODS

Pooled data from four placebo-controlled Phase 3 studies (N = 2,250) in patients with type 2 diabetes were used in the analyses. In each study, patients were treated with placebo, canagliflozin 100 mg or canagliflozin 300 mg, once daily for 26 weeks. Changes from baseline in body weight, HbA1c and SBP were measured at week 26, and the contribution of weight loss to the lowering of HbA1c and SBP was obtained using ANCOVA.

RESULTS

Canagliflozin 100 and 300 mg reduced mean body weight, HbA1c and SBP compared with placebo (p < 0.001 for each), and more patients had body-weight reductions >0%, ≥5% and ≥10% with canagliflozin treatment than with placebo. Weight-loss-independent and weight-loss-associated mechanisms contributed to HbA1c and SBP lowering with canagliflozin: ~85% of HbA1c lowering and ~60% of SBP lowering was independent of weight loss.

CONCLUSIONS/INTERPRETATION

In patients with type 2 diabetes, canagliflozin provided clinically meaningful body-weight reductions, and the weight loss contributed to reductions in HbA1c and SBP.

Long-term efficacy and safety of canagliflozin over 104 weeks in patients aged 55-80 years with type 2 diabetes

AIMS

The long-term efficacy and safety of canagliflozin, a sodium glucose co-transporter 2 inhibitor, was evaluated over 104 weeks in patients aged 55-80 years with type 2 diabetes mellitus (T2DM) inadequately controlled on a stable antihyperglycaemic agent regimen.

METHODS

In this randomized, double-blind, phase III study, patients received canagliflozin 100 or 300 mg or placebo once daily during a 26-week core period (N = 714) and a 78-week extension period (n = 624). Efficacy endpoints at week 104 included change from baseline in glycated haemoglobin (HbA1c), fasting plasma glucose (FPG) and systolic blood pressure, and percent change from baseline in body weight and fasting plasma lipids. Safety was assessed by adverse event (AE) reports.

RESULTS

At week 104, canagliflozin 100 and 300 mg were associated with reductions in HbA1c versus placebo (-0.32 and -0.43% vs 0.17%, respectively; overall mean baseline, 7.7%) and more patients achieved HbA1c <7.0% with canagliflozin 100 and 300 mg than with placebo (35.8 and 41.9% vs 20.3%, respectively). Reductions in FPG, body weight and systolic blood pressure, and increases in high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were seen with canagliflozin compared with placebo. The overall incidence rates of AEs over 104 weeks were 88.0, 89.8 and 86.1% with canagliflozin 100 and 300 mg and placebo, respectively; serious AE rates were low across treatment groups. The incidence rates of urinary tract infections, genital mycotic infections and osmotic diuresis- and volume depletion-related AEs were higher with canagliflozin than with placebo.

CONCLUSION

Canagliflozin improved glycaemic control, reduced body weight and systolic blood pressure, and was generally well tolerated in patients aged 55-80 years with T2DM over 104 weeks.

Long-term efficacy and safety of canagliflozin monotherapy in patients with type 2 diabetes inadequately controlled with diet and exercise: findings from the 52-week CANTATA-M study

OBJECTIVE

Canagliflozin is a sodium glucose co-transporter 2 inhibitor developed for treatment of type 2 diabetes mellitus (T2DM). The long-term efficacy and safety of canagliflozin monotherapy were evaluated over 52 weeks in patients with T2DM inadequately controlled with diet and exercise.

RESEARCH DESIGN AND METHODS

This randomized, double-blind, Phase 3 study included a placebo-controlled, 26-week core period (canagliflozin 100 or 300 mg vs placebo) and an active-controlled, 26-week extension (blinded switch of placebo-treated patients to sitagliptin 100 mg [placebo/sitagliptin]).

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01081834.

MAIN OUTCOME MEASURES

Efficacy endpoints assessed at 52 weeks included changes in hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), and systolic blood pressure (BP); and percentage changes in body weight and fasting plasma lipids. Adverse events (AEs) were recorded throughout the study. Efficacy data are reported for canagliflozin 100 and 300 mg (placebo/sitagliptin group was used to maintain the double-blind and to serve as a control group for safety purposes; not as an efficacy comparator); safety data are reported for canagliflozin 100 and 300 mg and placebo/sitagliptin.

RESULTS

Efficacy analyses included 451 patients who were randomized and dosed, entered the extension, and did not receive rescue therapy during the core period. Safety analyses included 584 patients who were randomized and dosed. At Week 52, canagliflozin 100 and 300 mg provided dose-related decreases from baseline in HbA1c of -0.81% and -1.11%. Canagliflozin 100 and 300 mg decreased FPG (-1.5 and -2.2 mmol/L [-27.4 and -39.1 mg/dL]), body weight (-3.3% and -4.4%), and systolic BP (-1.4 and -3.9 mmHg); decreased triglycerides and increased HDL-C and LDL-C were also seen. Over 52 weeks, overall AE rates were 67.2%, 66.0%, and 64.1% with canagliflozin 100 and 300 mg and placebo/sitagliptin; rates of serious AEs and AE-related discontinuations were low across groups. Compared with placebo/sitagliptin, canagliflozin was associated with higher rates of genital mycotic infections and AEs related to osmotic diuresis; these led to few discontinuations. Rates of volume depletion AEs and documented hypoglycemia were low across groups.

CONCLUSIONS

Canagliflozin monotherapy provided sustained improvement in glycemic control and body weight reduction, and was generally well tolerated in patients with T2DM over 52 weeks.

Efficacy and safety of canagliflozin treatment in older subjects with type 2 diabetes mellitus: a randomized trial

INTRODUCTION

Canagliflozin is a sodium glucose co-transporter 2 inhibitor developed for the treatment of patients with type 2 diabetes mellitus (T2DM). Our randomized, double-blind, placebo-controlled, phase 3 study (www.clinicaltrials.gov: NCT01106651) evaluated the efficacy and safety of canagliflozin therapy in older subjects (aged 55-80 years) with T2DM inadequately controlled on their current regimen of blood glucose-lowering agents (any approved oral or injectable treatment).

METHODS

Subjects (N = 716) aged 55 to 80 years (mean, 63.6 years) with glycated hemoglobin (HbA1c) levels ≥ 7.0% to ≤ 10.0% were randomized. Seven hundred fourteen received canagliflozin 100 mg or 300 mg or placebo (1:1:1) daily. The prespecified primary endpoint was change from baseline in HbA1c level at week 26. Prespecified secondary endpoints included proportion of subjects achieving HbA1c levels < 7.0%, change from baseline in fasting plasma glucose (FPG) level and systolic blood pressure (BP), and percent change from baseline in body weight, triglyceride levels, and high-density lipoprotein cholesterol (HDL-C) level. Adverse events (AEs) were reported throughout the study.

RESULTS

At week 26, treatment with canagliflozin 100 mg and 300 mg significantly reduced HbA1c levels compared with placebo (-0.60%, -0.73%, -0.03%, respectively; P < 0.001); more subjects achieved HbA1c levels < 7.0% with both canagliflozin doses compared with placebo (P < 0.001). Both canagliflozin doses significantly reduced body weight, FPG level, and systolic BP, and increased HDL-C level compared with placebo (P < 0.001); low-density lipoprotein cholesterol level was increased with both canagliflozin doses compared with placebo. The overall AE incidence was slightly higher with canagliflozin 300 mg than with canagliflozin 100 mg or placebo (78.0%, 72.2%, 73.4%, respectively). Serious AE and AE-related discontinuation rates were low across groups. Both canagliflozin doses were associated with higher rates than placebo of genital mycotic infections, urinary tract infections, and osmotic diuresis-related AEs (ie, pollakiuria, polyuria). Documented hypoglycemia rates were modestly higher with both canagliflozin doses compared with placebo.

CONCLUSION

Canagliflozin improved glycemic control, reduced body weight and systolic BP, and was generally well tolerated in older subjects with T2DM who were on background therapy with a variety of blood glucose-lowering agents.

Increased postprandial energy expenditure may explain superior long term weight loss after Roux-en-Y gastric bypass compared to vertical banded gastroplasty

Background and Aims

Gastric bypass results in greater weight loss than Vertical banded gastroplasty (VBG), but the underlying mechanisms remain unclear. In addition to effects on energy intake the two bariatric techniques may differentially influence energy expenditure (EE). Gastric bypass in rats increases postprandial EE enough to result in elevated EE over 24 hours. This study aimed to investigate alterations in postprandial EE after gastric bypass and VBG in humans.

Methods

Fourteen women from a randomized clinical trial between gastric bypass (n = 7) and VBG (n = 7) were included. Nine years postoperatively and at weight stability patients were assessed for body composition and calorie intake. EE was measured using indirect calorimetry in a respiratory chamber over 24 hours and focused on the periods surrounding meals and sleep. Blood samples were analysed for postprandial gut hormone responses.

Results

Groups did not differ regarding body composition or food intake either preoperatively or at study visit. Gastric bypass patients had higher EE postprandially (p = 0.018) and over 24 hours (p = 0.048) compared to VBG patients. Postprandial peptide YY (PYY) and glucagon like peptide 1 (GLP-1) levels were higher after gastric bypass (both p<0.001).

Conclusions

Gastric bypass patients have greater meal induced EE and total 24 hours EE compared to VBG patients when assessed 9 years postoperatively. Postprandial satiety gut hormone responses were exaggerated after gastric bypass compared to VBG. Long-term weight loss maintenance may require significant changes in several physiological mechanisms which will be important to understand if non-surgical approaches are to mimic the effects of bariatric surgery.

Efficacy and safety of canagliflozin monotherapy in subjects with type 2 diabetes mellitus inadequately controlled with diet and exercise

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor in development for type 2 diabetes mellitus (T2DM). The efficacy and safety of canagliflozin were evaluated in subjects with T2DM inadequately controlled with diet and exercise.

METHODS

In this 26-week, randomized, double-blind, placebo-controlled, phase 3 trial, subjects (N = 584) received canagliflozin 100 or 300 mg or placebo once daily. Primary endpoint was the change from baseline in haemoglobin A1c (HbA1c) at week 26. Secondary endpoints included the proportion of subjects achieving HbA1c < 7.0%; change from baseline in fasting plasma glucose (FPG), 2-h postprandial glucose (PPG) and systolic blood pressure (BP); and percent change in body weight, high-density lipoprotein cholesterol (HDL-C) and triglycerides. Adverse events (AEs) were recorded throughout the study.

RESULTS

At week 26, HbA1c was significantly reduced from baseline with canagliflozin 100 and 300 mg compared with placebo (-0.77, -1.03 and 0.14%, respectively; p < 0.001 for both). Both canagliflozin doses significantly decreased FPG, 2-h PPG, body weight and systolic BP (p < 0.001 for all), and increased HDL-C compared with placebo (p < 0.01 for both). Overall incidences of AEs were modestly higher with canagliflozin versus placebo; rates of serious AEs and AE-related discontinuations were low and similar across groups. Incidences of genital mycotic infections, urinary tract infections and osmotic diuresis-related AEs were higher with canagliflozin; these led to few discontinuations. The incidence of hypoglycaemia was low across groups.

CONCLUSION

Canagliflozin treatment improved glycaemic control, reduced body weight and was generally well tolerated in subjects with T2DM inadequately controlled with diet and exercise.

Central nervous system lipocalin-type prostaglandin D2-synthase is correlated with orexigenic neuropeptides, visceral adiposity and markers of the hypothalamic-pituitary-adrenal axis in obese humans

Lipocalin-type prostaglandin D2-synthase (L-PGDS) is the main producer of prostaglandin D2 (PGD2) in the central nervous system (CNS). Animal data suggest effects of central nervous L-PGDS in the regulation of food intake and obesity. No human data are available. We hypothesised that a role for CNS L-PGDS in metabolic function in humans would be reflected by correlations with known orexigenic neuropeptides. Cerebrospinal fluid (CSF) and serum samples were retrieved from 26 subjects in a weight loss study, comprising a 3-week dietary lead-in followed by 12-weeks of leptin or placebo treatment. At baseline, CSF L-PGDS was positively correlated with neuropeptide Y (NPY) (ρ = 0.695, P < 0.001, n = 26) and galanin (ρ = 0.651, P < 0.001) as well as visceral adipose tissue (ρ = 0.415, P = 0.035). Furthermore, CSF L-PGDS was inversely correlated with CSF leptin (ρ = -0.529, P = 0.005) and tended to correlate inversely with s.c. adipose tissue (ρ = -0.346, P = 0.084). As reported earlier, leptin treatment had no effect on weight loss and did not affect CSF L-PGDS or NPY levels compared to placebo. After weight loss, the change of CSF L-PGDS was significantly correlated with the change of CSF NPY levels (ρ = 0.604, P = 0.004, n = 21). Because of the correlation between baseline CSF L-PGDS levels and visceral adipose tissue, we examined associations with hypothalamic-pituitary-adrenal (HPA) axis components. Baseline CSF L-PGDS was correlated with corticotrophin-releasing hormone (ρ = 0.764, P < 0.001) and β-endorphin (ρ = 0.491, P < 0.001). By contrast, serum L-PGDS was not correlated with any of the measured variables either at baseline or after treatment. In summary, CSF L-PGDS was correlated with orexigenic neuropeptides, visceral fat distribution and central HPA axis mediators. The importance of these findings is unclear but could suggest a role for CSF L-PGDS in the regulation of visceral obesity by interaction with the neuroendocrine circuits regulating appetite and fat distribution. Further interventional studies will be needed to characterise these interactions in more detail.

Saxagliptin and metformin XR combination therapy provides glycemic control over 24 hours in patients with T2DM inadequately controlled with metformin

OBJECTIVE

To assess 24-hour glycemic control with saxagliptin compared with placebo as add-on treatment to metformin in patients with type 2 diabetes mellitus (T2DM) and inadequate glycemic control.

RESEARCH DESIGN AND METHODS

This was a 4-week, multicenter, randomized, double-blind, placebo-controlled Phase IIIb trial comparing the antihyperglycemic activity of saxagliptin 5 mg once daily in combination with a stable dose of metformin extended release (XR) vs. placebo in combination with metformin XR in patients with T2DM inadequately controlled (screening glycated hemoglobin [HbA(1c)] 7-10%) with stable doses of metformin immediate release or metformin XR ≥ 1500 mg/day. Ninety-three adult patients were randomized and received treatment. The primary outcome measure was change from baseline to week 4 in 24-hour mean weighted glucose (MWG).

RESULTS

The reduction from baseline in 24-hour MWG was significantly greater for saxagliptin 5 mg + metformin XR (-13.8 mg/dL; -0.77 mmol/L) compared with placebo + metformin XR (3.0 mg/dL; 0.17 mmol/L) (p = 0.0001). At week 4, the mean decrease in plasma glucose was sustained through a 24-hour period in saxagliptin-treated patients. Treatment with saxagliptin 5 mg + metformin XR resulted in significant mean reductions from baseline in 4-hour mean weighted postprandial glucose (PPG), 2-hour PPG, 3-day average mean daily glucose, and fasting plasma glucose levels compared with placebo + metformin XR (p ≤ 0.001). The proportion of adverse events (AEs) was similar in the two treatment groups, with no reported hypoglycemic AEs in saxagliptin-treated patients. The 4-week evaluation period may have been insufficient to evaluate longer term effects on hyperglycemia or to identify additional AEs.

CONCLUSIONS

In patients with T2DM treated with metformin XR, saxagliptin 5 mg orally administered once daily in the evening for 4 weeks effectively lowered plasma glucose concentrations through the 24-hour dosing interval and was well tolerated.

Feasibility of bariatric surgery as a strategy for secondary prevention in cardiovascular disease: a report from the Swedish obese subjects trial

Aims. Evaluation of bariatric surgery as secondary prevention in obese patients with ischemic heart disease (IHD). Methods. Analysis of data from 4047 subjects in the Swedish Obese Subjects (SOSs) study. Thirty-five patients with IHD are treated with bariatric surgery (n = 21) or conventional treatment (n = 14). Mean follow-up is 10.8 years. Results. Bariatric surgery resulted in sustained weight loss during the study period. After 2 years, the surgery group displayed significant reductions in cardiovascular risk factors, relief from cardiorespiratory symptoms, increments in physical activity, and improved quality of life. After 10 years, recovery from hypertension, diabetes, physical inactivity, and depression was still more common in the surgery group. There were no signs of increased cardiovascular morbidity or mortality in the surgery group. Conclusion. Bariatric surgery appears to be a safe and feasible treatment to achieve long-term weight loss and improvement in cardiovascular risk factors, symptoms, and quality of life in obese subjects with IHD.

Effects of bariatric surgery on cancer incidence in obese patients in Sweden (Swedish Obese Subjects Study): a prospective, controlled intervention trial

BACKGROUND

Obesity is a risk factor for cancer. Intentional weight loss in the obese might protect against malignancy, but evidence is limited. To our knowledge, the Swedish Obese Subjects (SOS) study is the first intervention trial in the obese population to provide prospective, controlled cancer-incidence data.

METHODS

The SOS study started in 1987 and involved 2010 obese patients (body-mass index [BMI] >or=34 kg/m(2) in men, and >or=38 kg/m(2) in women) who underwent bariatric surgery and 2037 contemporaneously matched obese controls, who received conventional treatment. While the main endpoint of SOS was overall mortality, the main outcome of this exploratory report was cancer incidence until Dec 31, 2005. Cancer follow-up rate was 99.9% and the median follow-up time was 10.9 years (range 0-18.1 years).

FINDINGS

Bariatric surgery resulted in a sustained mean weight reduction of 19.9 kg (SD 15.6 kg) over 10 years, whereas the mean weight change in controls was a gain of 1.3 kg (SD 13.7 kg). The number of first-time cancers after inclusion was lower in the surgery group (n=117) than in the control group (n=169; HR 0.67, 95% CI 0.53-0.85, p=0.0009). The sex-treatment interaction p value was 0.054. In women, the number of first-time cancers after inclusion was lower in the surgery group (n=79) than in the control group (n=130; HR 0.58, 0.44-0.77; p=0.0001), whereas there was no effect of surgery in men (38 in the surgery group vs 39 in the control group; HR 0.97, 0.62-1.52; p=0.90). Similar results were obtained after exclusion of all cancer cases during the first 3 years of the intervention.

INTERPRETATION

Bariatric surgery was associated with reduced cancer incidence in obese women but not in obese men.

FUNDING

Swedish Research Council, Swedish Foundation for Strategic Research, Swedish Federal Government under the LUA/ALF agreement, Hoffmann La Roche, Cederoths, AstraZeneca, Sanofi-Aventis, Ethicon Endosurgery.

Effects of bariatric surgery on mortality in Swedish obese subjects

BACKGROUND

Obesity is associated with increased mortality. Weight loss improves cardiovascular risk factors, but no prospective interventional studies have reported whether weight loss decreases overall mortality. In fact, many observational studies suggest that weight reduction is associated with increased mortality.

METHODS

The prospective, controlled Swedish Obese Subjects study involved 4047 obese subjects. Of these subjects, 2010 underwent bariatric surgery (surgery group) and 2037 received conventional treatment (matched control group). We report on overall mortality during an average of 10.9 years of follow-up. At the time of the analysis (November 1, 2005), vital status was known for all but three subjects (follow-up rate, 99.9%).

RESULTS

The average weight change in control subjects was less than +/-2% during the period of up to 15 years during which weights were recorded. Maximum weight losses in the surgical subgroups were observed after 1 to 2 years: gastric bypass, 32%; vertical-banded gastroplasty, 25%; and banding, 20%. After 10 years, the weight losses from baseline were stabilized at 25%, 16%, and 14%, respectively. There were 129 deaths in the control group and 101 deaths in the surgery group. The unadjusted overall hazard ratio was 0.76 in the surgery group (P=0.04), as compared with the control group, and the hazard ratio adjusted for sex, age, and risk factors was 0.71 (P=0.01). The most common causes of death were myocardial infarction (control group, 25 subjects; surgery group, 13 subjects) and cancer (control group, 47; surgery group, 29).

CONCLUSIONS

Bariatric surgery for severe obesity is associated with long-term weight loss and decreased overall mortality.

Two year reduction in sleep apnea symptoms and associated diabetes incidence after weight loss in severe obesity

STUDY OBJECTIVES

To evaluate the effect of bariatric surgery on sleep apnea symptoms and obesity-associated morbidity in patients with severe obesity.

DESIGN

Prospective study.

SETTING

University hospitals and community centers in Sweden.

INTERVENTION

We investigated the influence of weight loss surgery (n=1729) on sleep apnea symptoms and obesity-related morbidity using a conservatively treated group (n=1748) as a control.

MEASUREMENTS AND RESULTS

Baseline BMI in surgical group (42.2+/-4.4 kg/m(2)) and control group (40.1+/-4.6 kg/m(2)) changed -9.7+/-5 kg/m(2) and 0+/-3 kg/m(2), respectively, at 2-year follow-up. In the surgery group, there was a marked improvement in all obstructive sleep apnea (OSA) symptoms compared with the control group (P <0.001). Persistence of snoring (21.6 vs 65.5%, adjusted OR 0.14, 95% CI 0.10-0.19) and apnea (27.9 vs 71.3%, adjusted OR 0.16, 95% I 0.10-0.23) were much less in the surgery group compared with controls. Compared with subjects with no observed apnea at follow-up (n=2453), subjects who continued to have or developed observed apnea (n=404) had a higher incidence of diabetes (adjusted OR 2.03, 95% CI 1.19-3.47) and hypertriglyceridemia (adjusted OR 1.86, 95% CI 1.07-3.25) but not hypertension (adjusted OR 1.09, 95% CI 0.65-1.83) or hypercholesterolemia (adjusted OR 0.91, 95% CI 0.53-1.58).

CONCLUSION

Bariatric surgery results in a marked improvement in sleep apnea symptoms at 2 years. Despite adjustment for weight change and baseline central obesity, subjects reporting loss of OSA symptoms had a lower 2-year incidence of diabetes and hypertriglyceridemia. Improvement in OSA in patients losing weight may provide health benefits in addition to weight loss alone.

Topiramate in the treatment of obese subjects with drug-naive type 2 diabetes

AIM

The aim of this study was to examine the efficacy and safety of topiramate as an adjunct to diet and exercise in drug-naive, obese subjects with type 2 diabetes.

METHODS

Drug-naive individuals with type 2 diabetes, body mass index (BMI) of > or =27 and <50 kg/m(2) and haemoglobin A(1c) (HbA(1c)) of <10.5% were enrolled into the study. All the individuals participated in a non-pharmacologic weight loss program (Pathways to Change((R)); Johnson & Johnson Healthcare Systems, Piscataway, NJ, USA) throughout the trial. After a 6-week placebo run-in, the subjects were randomized to placebo, topiramate 96 mg/day or topiramate 192 mg/day. Subjects were scheduled for 8-week titration and 52-week maintenance phases. The study was ended early; efficacy data were reported for a predefined modified intent-to-treat (MITT) population (n = 229), with 40 weeks of treatment. All the subjects who provided any safety data were included in the safety population (n = 535).

RESULTS

Baseline mean weight was 103.7 kg, BMI 36 kg/m(2) and HbA(1c) 6.7% across all treatment groups. By the end of week 40, the placebo, the topiramate 96 mg/day and topiramate 192 mg/day groups lost 2.5, 6.6 and 9.1% of their baseline body weight respectively (p < 0.001 vs. placebo, MITT population using last observation carried forward). The decrease in HbA(1c) was 0.2, 0.6 and 0.7% respectively (p < 0.001 vs. placebo, MITT). Topiramate significantly reduced blood pressure and urinary albumin excretion; a weight-loss-independent HbA(1c) improving effect of topiramate was demonstrated. Adverse events were predominantly related to central nervous system (CNS).

CONCLUSIONS

Topiramate as an add-on treatment to lifestyle improvements produced significant weight loss and improved glucose homeostasis in obese, drug-naive subjects with type 2 diabetes. These treatment advantages should be balanced against the occurrence of adverse events in the CNS.

Interleukin-6 levels in the central nervous system are negatively correlated with fat mass in overweight/obese subjects

Recently, we demonstrated that intracerebroventricular injection of IL-6 increases energy expenditure and decreases body fat in rodents. Therefore, IL-6 may play a role in appetite and body weight control in the central nervous system. In the present study we evaluated cerebrospinal fluid (CSF) and serum IL-6 levels in humans in relation to body fat content and to CSF and serum levels of leptin. Thirty-two healthy overweight/obese male subjects with a body mass index range of 29.3-36.0 kg/m(2) were studied. Total and sc body fat were measured by dual energy x-ray absorptiometry and computed tomography, respectively. CSF IL-6 levels were in some individuals higher than serum IL-6 levels and correlated negatively with total body weight, sc and total body fat. In contrast, CSF leptin levels were 30-60 times lower than serum leptin levels and correlated positively with serum leptin, body weight, sc and total body fat. Furthermore, there was a negative correlation between CSF IL-6 and leptin. In conclusion, CSF IL-6 differs in many ways from CSF leptin. CSF IL-6 may be locally produced rather than serum derived, and body fat-regulating regions in the central nervous system may be exposed to insufficient IL-6 levels in more severe obesity.

Relief of cardiorespiratory symptoms and increased physical activity after surgically induced weight loss: results from the Swedish Obese Subjects study

BACKGROUND

Obese people frequently suffer from shortness of breath and chest discomfort on exertion, and they often have a sedentary lifestyle. In the present study of patients with severe obesity, we investigated the effects of surgically induced weight loss on cardiorespiratory symptoms and leisure-time physical activity.

METHODS

The Swedish Obese Subjects study is an ongoing intervention trial of obesity consisting of 1 surgically treated group and 1 matched control group. Information on smoking habits, hypertension, diabetes, and sleep apnea was obtained from 1210 surgical cases and 1099 controls who were observed for 2 years. Patients were also asked about symptoms of breathlessness and chest pain and their levels of leisure-time physical activity.

RESULTS

The surgically treated group displayed a mean weight loss of 28 kg (23%) compared with the control group in which the average weight remained unchanged (P<.001). The rates of hypertension, diabetes, and apneas during sleep decreased in surgical cases compared with controls (P<.001), while smoking habits remained largely the same. The surgical group also displayed highly significant improvements in dyspnea and chest pain and increases in physical activity compared with the control group (P<.001). The odds ratio for self-reported breathlessness, chest discomfort, or sedentary behavior after 2 years decreased progressively with the degree of weight loss. Furthermore, patients who recovered from apneas during sleep reduced their odds of having dyspnea and chest discomfort at follow-up, independent of changes in weight.

CONCLUSIONS

Surgically induced weight loss in patients with severe obesity is associated with a marked relief in symptoms of dyspnea and chest pain and promotes increased leisure-time physical activity. Sleep-disordered breathing may be involved in the pathophysiology of breathlessness and chest discomfort in obese subjects.

A low serum leptin level at baseline and a large early decline in leptin predict a large 1-year weight reduction in energy-restricted obese humans

The difficulty in maintaining weight loss during obesity treatment may be caused by a counteracting neuroendocrine response. It has been proposed that leptin could be a regulator of this response. We examined the relations between leptin levels during an initial very low calorie diet, other simultaneous endocrine changes, and the 1-yr weight reduction. Sixty-nine obese (24 men and 45 women) were treated with very low calorie diet for 16 weeks, followed by a hypocaloric diet for 32 weeks. Serum levels of leptin, insulin, cortisol, and thyroid hormones were measured at weeks 0, 8, and 18. The relative weight reductions after 18 and 48 weeks were 20.1% and 14.4% in men and 15.4% and 11.8% in women. Low initial leptin levels and large declines in serum leptin were associated with a large 1-yr weight loss in both genders. Leptin levels (baseline or changes) were not independently associated with the changes in insulin, cortisol, or thyroid hormones. Our results may indicate that leptin by itself could be of minor importance for the neuroendocrine response to severe caloric restriction in humans.

Body weight and body composition changes after treatment of hyperthyroidism

Body composition changes in nine adults with hyperthyroidism were determined with dual energy x-ray absorptiometry and computed tomography at diagnosis and after 3 and 12 months of euthyroidism achieved by surgery, antithyroid drugs, or treatment with radioiodine. Mean body weight was 67.6 kg at diagnosis and increased 2.7 kg (P=0.06) and 8.7 kg (P < 0.001) after 3 and 12 months of euthyroidism, respectively. Basal metabolic rate decreased from 2087 Cal/24 h at diagnosis to 1601 Cal/24 h at 12 months (P=0.001), whereas reported energy intake dropped from 3244 to 2436 Cal/24 h (P=0.01). According to dual energy x-ray absorptiometry, body fat was unchanged at 3 months, but increased by 5.3 kg (P < 0.0001) at 12 months. Fat-free mass increased 2.7 kg (P=0.003) at 3 months and 3.5 kg (P < 0.0001) at 12 months. Changes in bone mineral content and density did not reach significance. According to computed tomography, skeletal muscle plus skin areas increased by 11% (trunk) and 18% (thigh) at 3 months and by 17% (trunk) and 25% (thigh) at 12 months. There was no increase in sc adipose tissue (AT) at 3 months, but at 12 months this AT depot increased by 15% (thigh) and 33% (trunk). Intraperitoneal AT showed a borderline significant increase by 28% (P=0.08) at 3 months and by 40% (P=0.015) at 12 months. Areas of visceral organs and bone tissue of femur did not change significantly during the study. It is concluded that during early recovery from hyperthyroidism, priority is given to the replenishment of skeletal muscles and ip AT, whereas sc AT is increased at a later stage.

Familial predisposition for obesity may modify the predictive value of serum leptin concentrations for long-term weight change in obese women

Leptin is believed to play a role in regulating food intake and body weight. The aim of this study was to examine the influence of parental history of obesity on the association between baseline serum leptin concentrations and subsequent 4-y weight changes. Changes in food intake were also considered in the analysis. Middle-aged, obese women with no obese parent (n = 25) or at least one obese parent (n = 24) were included in the analysis. At baseline, women with no parental history of obesity and women with a parental history of obesity did not differ in body mass index (in kg/m2: 41.2 and 40.2, respectively) or median leptin concentrations (40.8 and 38.8 microg/L, respectively). Four-year weight changes varied widely in both groups combined (from -30 to 24 kg). Stratified regression analysis, adjusted for age, weight, and height, revealed that high leptin concentrations predicted less weight gain (or more weight loss) in women with no obese parent (beta = -21.2, P = 0.0006) but played no significant role in predicting weight gain in women with at least one obese parent (beta = -3.8, P = 0.41). Adding changes in energy and fat intakes to the model reduced the association between leptin and weight change to nonsignificance in the women with no obese parent, indicating that the effect of leptin could be explained largely by dietary changes. In conclusion, serum leptin concentrations predict long-term weight change in obese women with no history of parental obesity, an association largely mediated by changes in food intake.

Effects of growth hormone treatment on the leptin system and on energy expenditure in abdominally obese men

The present study has examined the short- and long-term effects of growth hormone (GH) treatment on the leptin system and energy expenditure. Thirty male individuals with abdominal obesity were randomised to GH or placebo treatment in a 9-month, double-blind study. The dose of GH was 9.5 microg/kg, administered subcutaneously every evening. Serum leptin concentrations were measured by a human leptin RIA. Total RNA was isolated from adipose tissue biopsies and leptin mRNA levels were determined by a semi-quantitative reverse transcriptase-PCR assay. Body composition was determined by potassium-40 and the basal metabolic rate (BMR) was measured by a computerised, ventilated, open-hood system. As compared with placebo, an overall decrease in serum leptin concentrations as assessed by the area under the curve (AUC) (P < 0.05) and an increase in BMR (AUC, P < 0.05) were observed during GH treatment. The overall GH-induced changes were due to marked changes in serum leptin concentrations and BMR after 6 weeks of treatment. After 9 months of GH treatment there was a significant reduction in body fat (BF) while serum leptin concentrations and BMR did not differ from baseline values. Leptin mRNA levels did not change over the study period. We speculate that long-term GH treatment induces a new energy balance steady state with decreased BF stores. The effects of GH on the leptin system is suggested to be of importance for the maintenance of a lower BF mass.

Diurnal variations in twenty-four-hour energy expenditure during growth hormone treatment of adults with pituitary deficiency

The effects of growth hormone (GH) treatment on 24-h energy expenditure (EE) were studied in a open trial over a period of 4 weeks. Five subjects, four men and one woman, with a history of complete GH deficiency were included. All the subjects were examined on 2 consecutive days on baseline and, thereafter, at six occasions during a period of 1 month (days 1, 2, 5, 8, 15, and 30). The dose of GH was 0.25 U/kg.week, administered sc once a day in the evening. EE was determined in a chamber for indirect calorimetry. Body composition was determined with dual-energy x-ray absorptiometry and computed tomography using a four-scan technique. Blood samples were examined using well-established RIAs. During the first 2 weeks, 24-h EE increased by 6 +/- 3% (range 1-8%) from 40.9 +/- 4.8 to 42.9 +/- 4.8 kcal/24 h.kg (P < 0.05), sleeping metabolic rate by 14 +/- 3% (range 10-18%) from 28.4 +/- 1.9 to 32.9 +/- 2.2 kcal/24h.kg (P < 0.001), and basal metabolic rate by 11 +/- 7% (range 0-18%) from 29.6 +/- 2.4 to 33.3 +/- 2.6 kcal/24h.kg (P < 0.05). No change was found in daytime EE. The increase in EE covaried with changes in insulin-like growth factor 1, the free T3/free T4 ratio, insulin-like growth factor-binding protein-3, and the aminoterminal procollagen III peptide but not with changes in body composition. It is suggested that the stimulating effect of GH on EE occurs gradually during a 2-week period and is only detectable during night and morning hours, when significant levels of GH occur.

Growth hormone treatment of abdominally obese men reduces abdominal fat mass, improves glucose and lipoprotein metabolism, and reduces diastolic blood pressure

The most central findings in both GH deficiency in adults and the metabolic syndrome are abdominal/visceral obesity and insulin resistance. Abdominal obesity is associated with blunted GH secretion and low serum insulin-like growth factor-I concentrations. GH treatment in GH-deficient adults has demonstrated favorable effects on most of the features of GH deficiency in adults, but it is not known whether GH can improve some of the metabolic aberrations observed in abdominal/visceral obesity. Thirty men, 48-66 yr old, with abdominal/visceral obesity were treated with recombinant human GH (rhGH) in a 9-month randomized, double-blind, placebo-controlled trial. The daily dose of rhGH was 9.5 micrograms/kg. Body fat was assessed from total body potassium, and abdominal sc and visceral adipose tissue was measured using computed tomography. The glucose disposal rate (GDR) was measured during an euglycemic, hyperinsulinemic glucose clamp. In response to the rhGH treatment, total body fat and abdominal sc and visceral adipose tissue decreased by 9.2 +/- 2.4%, 6.1 +/- 3.2%, and 18.1 +/- 7.6%, respectively. After an initial decrease in the GDR at 6 weeks, the GDR increased in the rhGH-treated group as compared with the placebo-treated one (P < 0.05). The mean serum concentrations of total cholesterol (P < 0.01) and triglyceride (P < 0.05) decreased, whereas blood glucose and serum insulin concentrations were unaffected by the rhGH treatment. Furthermore, diastolic blood pressure decreased and systolic blood pressure was unchanged in response to rhGH treatment. This trial has demonstrated that GH can favorably affect some of the multiple perturbations associated with abdominal/visceral obesity. This includes a reduction in abdominal/visceral obesity, an improved insulin sensitivity, and favorable effects on lipoprotein metabolism and diastolic blood pressure.

Energy expenditure in obstructive sleep apnea: effects of treatment with continuous positive airway pressure

We examined 24-h energy expenditure (EE) in a chamber for indirect calorimetry in five male patients with obstructive sleep apnea (OSA) and six snoring control subjects (snorers). The 24-h EE was remeasured in patients with OSA after 3-mo treatment with nasal continuous positive airway pressure (CPAP). Patients with OSA had a greater degree of severe sleep-breathing disturbance than snorers. Patients with OSA had higher 24-h EE [39.2 +/- 3.0 vs. 33.9 +/- 2.7 kcal.24 h-1.kg fat-free mass (FFM)-1, P < 0.05], daytime urinary norepinephrine and vanillylmandelic acid (VMA), and aminoterminal procollagen III peptide (PIIIp) levels, and they tended to have higher sleeping EE (32.4 +/- 4.1 vs. 26.3 +/- 1.9 kcal.24 h-1.kg FFM-1, P < 0.1) than snorers. CPAP treatment normalized sleep architecture and breathing. CPAP treatment also decreased sleep EE (from 32.4 +/- 4.1 to 27.2 +/- 1.4 kcal.24 h-1.kg FFM-1, P < 0.05) and EE variability during sleep (from 1.6 +/- 0.5 to 1.0 +/- 0.5 kcal.24 h-1.kg FFM-1, P < 0.05) and increased the basal metabolic rate-to-sleep EE ratio in all subjects. Serum PIIIp and plasma norepinephrine decreased after CPAP in all patients. We conclude that OSA is associated with an increased sleep EE, which is normalized by treatment with CPAP.

Impact of self-reported sleep-breathing disturbances on psychosocial performance in the Swedish Obese Subjects (SOS) Study

Patients with severe obesity commonly have obstructive sleep apnea (OSA). In order to determine the impact of OSA on psychosocial morbidity in severe obesity, subjects enrolled in the Swedish Obese Subjects (SOS) Study were classified into two subgroups based on questionnaire data: one group with a high likelihood and one with a low likelihood of OSA. These groups were contrasted and multivariable analysis was used to examine whether OSA had independent effects on divorce rate, sick leave, work performance, income and self-estimated general health after adjustment for obesity, fat distribution, alcohol, smoking, medications and coexisting medical conditions. A high likelihood of OSA was identified in 338 men and 155 women, compared with 216 men and 481 women who had a low likelihood of OSA. Men with OSA were identical in age to men without OSA and had slightly higher levels of visceral fat (p = 0.01), but were similar in most psychosocial variables except self-perceived general health. Women with OSA were identical in age and visceral fat mass to women without OSA, but were characterized by a higher rate of impaired work performance, sick leave and divorce. When frequent sleepiness was used as an additional discriminator between OSA and non-OSA groups, marked differences in psychosocial morbidity were observed. Multivariable analysis revealed either OSA or frequent sleepiness or both to be independent predictors of amount of sick leave, worse self-rated general health, impaired work performance and divorce rate. Therefore OSA, measured by self report, is an important independent predictor of psychosocial morbidity in subjects with severe obesity.

Impact of obstructive sleep apnea and sleepiness on metabolic and cardiovascular risk factors in the Swedish Obese Subjects (SOS) Study

OBJECTIVE

To determine if obstructive sleep apnea (OSA) is independently associated with cardiovascular risk factors and health status in subjects with severe obesity.

DESIGN

Cross-sectional analysis of epidemiological data.

SUBJECTS

3034 participants in the Swedish Obese Subjects (SOS) Cohort. Two sub-groups with a high and low likelihood for OSA based on questionnaire data were analysed in detail.

MEASUREMENTS

General health questionnaires, anthropometric data including CT calibrated values for body fat distribution and lean body mass, blood pressure, fasting insulin, triglycerides, cholesterol, uric acid, glucose.

RESULTS

Self-reported loud snoring and observed breathing pauses (high likelihood of OSA) was associated with increased frequency of WHO Grade 4 dyspnea, admissions to hospital with chest pain, myocardial infarction, blood pressure, fasting insulin, fasting triglyceride (women only), uric acid (women only) after adjustment for body fat distribution and other potential confounders.

CONCLUSION

OSA may be another medical disorder which contributes to morbidity in severe obesity and is associated with some of the components of the metabolic syndrome observed in the centrally obese.

Effects of recombinant human growth hormone on basal metabolic rate in adults with pituitary deficiency

The effect of recombinant human growth hormone (rhGH) on basal metabolic rate (BMR) was studied in a placebo-controlled, double-blind, crossover trial. Ten patients with a history of complete pituitary insufficiency were randomized for 26 weeks in each period. Three patients were excluded due to withdrawal, fever, and claustrophobia, respectively. All patients had received adrenal, thyroid, and gonadal substitution therapy for at least 1 year before the study. The dose of rhGH was 0.25 to 0.5 U/kg/wk, administered subcutaneously once a day in the evening. BMR was determined by indirect calorimetry in a computerized ventilated open-hood system. Body composition was examined using four different methods--computed tomography (CT), tritium dilution, 40K determinations, and total body nitrogen (TBN) measured with neutron activation. The body composition data have previously been reported. Fat-free mass (FFM) increased and body fat (BF) decreased during the first 6 weeks of rhGH treatment, but no further changes in body composition occurred between 6 and 26 weeks. Baseline BMRs in GH-deficient (GHD) patients were in the lower part of the reference range, but BMR and the ratio between BMR and FFM (BMR/FFM) were not significantly lower than in a carefully selected control group. BMR increased between 0 and 6 weeks (mean +/- SD: from 6.68 +/- 1.55 to 7.75 +/- 1.35 MJ/24 h, P < .001) and then remained unchanged between 6 and 26 weeks. The increase in BMR was closely related to the increase in FFM (r = .91, P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Thyroid hormones, procollagen III peptide, body composition and basal metabolic rate in euthyroid individuals

We examined 103 euthyroid men and women within a wide range of body weights and ages. Fat free mass (FFM) and body fat (BF) were determined with the total body potassium technique, basal metabolic rate (BMR) by indirect calorimetry and serum concentrations of thyroid hormones (free and total T3 and T4) and the aminoterminal propeptide of collagen III (pIIIp) by immunoassays. BMR was positively related to FFM, BF, total T3, the free T3/free T4 ratio and pIIIp, and negatively to free T4 (men) and to the ratios free T4/total T4 and free T3/total T3. pIIIp was as strongly related to BMR as to total T3. It is suggested that pIIIp may serve as an indicator of peripheral energy expenditure. The negative relationship between BMR and free T4 was unexpected and different to the situation in hypo- and hyperthyreosis where BMR and thyroid hormone are positively related. Our hypothesis is that euthyroid subjects with low serum free thyroid hormone concentrations and comparatively high BMR may have high intracellular thyroid hormone concentrations.