The Peripheral Neuropathy Prevalence and Characteristics Are Comparable in People with Obesity and Long-Duration Type 1 Diabetes

Introduction

Peripheral neuropathy is reported in obesity even in the absence of hyperglycaemia.

Objective

To compare the prevalence and characterise the phenotype of peripheral neuropathy in people living with obesity (OB) and long-duration type 1 diabetes (T1D).

Patients and Methods

We performed a prospective cross-sectional study of 130 participants including healthy volunteers (HV) (n = 28), people with T1D (n = 51), and OB (BMI 30–50 kg/m²) (n = 51). Participants underwent assessment of neuropathic symptoms (Neuropathy Symptom Profile, NSP), neurological deficits (Neuropathy Disability Score, NDS), vibration perception threshold (VPT) and evaluation of sural nerve conduction velocity and amplitude.

Results

Peripheral neuropathy was present in 43.1% of people with T1D (age 49.9 ± 12.9 years; duration of diabetes 23.4 ± 13.5 years) and 33.3% of OB (age 48.2 ± 10.8 years). VPT for high risk of neuropathic foot ulceration (VPT ≥ 25 V) was present in 31.4% of T1D and 19.6% of OB. Participants living with OB were heavier (BMI 42.9 ± 3.5 kg/m²) and had greater centripetal adiposity with an increased body fat percentage (FM%) (P < 0.001) and waist circumference (WC) (P < 0.001) compared to T1D. The OB group had a higher NDS (P < 0.001), VAS for pain (P < 0.001), NSP (P < 0.001), VPT (P < 0.001) and reduced sural nerve conduction velocity (P < 0.001) and amplitude (P < 0.001) compared to HV, but these parameters were comparable in T1D. VPT was positively associated with increased WC (P = 0.011), FM% (P = 0.001) and HbA1c (P < 0.001) after adjusting for age (R² = 0.547). Subgroup analysis of respiratory quotient (RQ) measured in the OB group did not correlate with VPT (P = 0.788), nerve conduction velocity (P = 0.743) or amplitude (P = 0.677).

Conclusion

The characteristics of peripheral neuropathy were comparable between normoglycaemic people living with obesity and people with long-duration T1D, suggesting that metabolic factors linked to obesity play a pivotal role in the development of peripheral neuropathy. Further studies are needed to investigate the mechanistic link between visceral adiposity and neuropathy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02208-z.

Mechanisms, screening modalities and treatment options for individuals with non-alcoholic fatty liver disease and type 2 diabetes

Non-alcoholic fatty liver disease (NAFLD) exists as a spectrum of disease ranging from excessive accumulation of fat within the liver (simple steatosis), inflammation (non-alcoholic steatohepatitis) through to fibrosis, cirrhosis and end-stage liver disease. There is also an increased risk of hepatocellular carcinoma. The principal risk factor for NAFLD is overweight or obesity, along with type 2 diabetes, and NAFLD itself is also a risk factor for incident type 2 diabetes. Overweight/obesity is synergistic with alcohol consumption in causing progressive and insidious liver damage. Recent consensus advocates a change in nomenclature from NAFLD to 'metabolic associated fatty liver disease' (MAFLD), reflective of the associated metabolic abnormalities (insulin resistance/type 2 diabetes and metabolic syndrome components). Additional extra-hepatic manifestations of NAFLD include cardiovascular disease, chronic kidney disease and certain cancers. Unlike other micro- and macrovascular complications of type 2 diabetes, systematic screening or surveillance protocols have not been widely adopted in routine diabetes care to assess for presence/severity of NAFLD. Various screening tools are available (non-invasive tests and biochemical indices) combined with imaging techniques (e.g. transient elastography) to detect steatosis and more importantly advanced fibrosis/cirrhosis to facilitate appropriate surveillance. Liver biopsy may be sometimes necessary. Treatment options for type 2 diabetes, including lifestyle interventions (dietary change and physical activity), glucose-lowering therapies and metabolic surgery, can modulate hepatic steatosis and to a lesser extent fibrosis. Awareness of the impact of liver disease on the choice of glucose-lowering medications in individuals with type 2 diabetes is also critical.

192Effect of dapagliflozin on cardiovascular outcomes in patients with type 2 diabetes according to baseline renal function and albuminuria status: Insights from DECLARE-TIMI 58

Background

Renal dysfunction including both reduced estimated glomerular filtration rate (eGFR) and the presence of albuminuria have each been shown to predict cardiovascular (CV) outcomes. Sodium glucose co-transporter 2 inhibitors (SGLT2i), which promote glucose excretion in the kidneys, reduce CV events and hospitalizations for heart failure (HHF) in patients with type 2 diabetes mellitus (T2DM).

Purpose

To analyze the CV efficacy of dapagliflozin according to baseline renal function and albuminuria status in DECLARE-TIMI 58.

Methods

The DECLARE-TIMI 58 trial compared dapagliflozin vs. placebo in 17,160 patients with T2DM and a creatinine clearance >60 ml/min/1.73m2 at enrollment. The dual primary endpoints were CV death/HHF and MACE (MI, stroke, CV death). We categorized patients according baseline eGFR [<60 vs. ≥60 ml/min/1.73m2 according to the CKD-EPI formula] and urinary albumin:creatinine ratio (UACR) [<30 vs. ≥30 mg/g]. Cox regression models with interaction testing were applied. The Gail-Simon test was used to test for interaction of the absolute risk differences.

Results

In total, 5198 (30.3%) patients had albuminuria (UACR 30–300: n=4029; UACR >300: n=1169) and 1265 (7.4%) had an eGFR <60 ml/min/1.73m2. Accordingly, 10958 (63.9%) patients had no manifestation of CKD, 5367 (31.3%) had either an eGFR <60 ml/min/1.73m2 or albuminuria, and 548 (3.2%) patients had both manifestations. Patients with more abnormal markers had higher event rates for CV death/HHF (KM event rates at 4 years of 3.9%, 8.3%, 17.4%) and MACE (7.5%, 11.7%, and 18.9%) for no, 1, or 2 markers of CKD, respectively. The relative risk reductions for CV death/HHF and MACE were generally consistent across the subgroups (both P-interaction >0.29), though numerically greatest (42%) in patients with reduced eGFR and albuminuria. However, the absolute risk difference increased substantially in patients with greater kidney damage (absolute risk difference of CV death/HHF: −0.5%, −1.0%, and −8.3%, respectively; P-INT for ARD 0.002; Figure). See figure for MACE and component outcomes.

Conclusions

Patients with baseline renal disease had higher rates of adverse CV outcomes. Dapagliflozin reduced events with generally consistent relative risk, but reduced the absolute risk of CVD/HHF by the greatest amount in patients with kidney disease evidenced by both reduced eGFR and albuminuria.

Acknowledgement/Funding

AstraZeneca, Deutsche Forschungsgemeinschaft (ZE 1109/1-1)

Correction to: Adipokines and the insulin resistance syndrome in familial partial lipodystrophy caused by a mutation in lamin A/C

The authors regret that Alexandra Bargiota's name was spelt incorrectly in the author list. The details given in this correction are correct.

Beyond lifestyle interventions: exploring the potential of anti-obesity medications in the UK

In the UK, over one-quarter of the adult population have obesity (body mass index ≥30 kg m^-2 ). This has major implications for patients' health and the National Health Service. Despite published studies showing that significant weight loss can be achieved and maintained in primary care, and guidance from the National Institute for Health and Care Excellence, weight management services are inconsistently implemented. This may be due primarily to workload and financial constraints. There is also a lack of belief that specialist weight management services and anti-obesity medications (AOMs) are a viable alternative to bariatric surgery for long-term maintenance of weight loss. This article discusses the challenges facing obesity management and explores the reasons for the lack of investment in AOMs in the UK to date. The aim of this article is to identify whether the newer AOMs, such as naltrexone/bupropion and liraglutide 3.0 mg, are likely to perform better in a real-world setting than current or withdrawn AOMs. In addition, it considers whether the equitable provision of specialist weight management services and future clinical trial design could be improved to help identify those individuals most likely to benefit from AOMs and, thus, improve outcomes for people with obesity in the UK.

Evaluation of Aintree LOSS, a community-based, multidisciplinary weight management service: outcomes and predictors of engagement

Aintree LOSS is a community-based, multidisciplinary weight management programme for patients with severe and complex obesity, focusing on a flexible and individualized service with follow-up for up to 2 years. We evaluated all 2472 patients referred to the service between October 2009 and 2013. Demographic data were recorded at baseline, with the Index of Multiple Deprivation (IMD) used to measure socioeconomic deprivation. Weight was recorded at each visit. Mean body mass index at baseline was 45.6 (standard deviation 6.8), and 58.9% of patients lived in areas in the most deprived decile nationally. Of 2315 appropriate referrals, 1249 (55.1%) attended >2 visits; mean final weight loss was 3.50 ± 8.55 kg, and 24.1% achieved ≥5% weight loss. Of the patients, 754 (33.3%) attended for over 6 months; mean final weight loss was 4.94 ± 10 kg, and 34% achieved 5% weight loss. Multivariate logistic regression analysis showed increasing age, residence in a less deprived area and sleep apnoea to be independently associated with attendance for >6 months, and there was a linear relationship between 6-month attendance and deprivation quintile. Year-on-year analyses showed improvement in engagement over time, coinciding with efforts to improve access to the service. This work shows a multidisciplinary, community-based weight loss programme prioritizing a fully flexible and individualized approach functioning effectively in real-world practice. Maintaining engagement remains a challenge in weight loss programmes, and our results suggest younger patients living in areas with greater deprivation should be a target for efforts to improve engagement.

Screening methods for obstructive sleep apnoea in severely obese pregnant women

Obstructive sleep apnoea (OSA) is an often-overlooked diagnosis, more prevalent in the obese population. Screening method accuracy, uptake and hence diagnosis is variable. There is limited data available regarding the obese pregnant population; however, many studies highlight potential risks of apnoeic episodes to mother and foetus, including hypertension, diabetes and preeclampsia. A total of 162 women with a body mass index (BMI) ≥ 35 were recruited from a tertiary referral hospital in the northwest of England. They were invited to attend three research antenatal clinics, completing an Epworth Sleepiness Scale (ESS) questionnaire at each visit. A monitor measuring the apnoea hypopnoea index (AHI) was offered at the second visit. Data taken from consent forms, hospital notes and hospital computer records were collated and anonymized prior to statistical analysis. A total of 12.1% of women had an ESS score of >10, suggesting possible OSA. Rates increased throughout pregnancy, although unfortunately, the attrition rate was high; 29.0% of women used the RUSleeping (RUS) meter, and only one (2.1%) met pre-specified criteria for OSA (AHI ≥ 15). This individual had OSA categorized as severe and underwent investigations for preeclampsia, eventually delivering by emergency caesarean section due to foetal distress. The accuracy of the ESS questionnaire, particularly the RUS monitor, to screen for OSA in the pregnant population remains unclear. Further research on a larger sample size using more user-friendly technology to confidently measure AHI would be beneficial. There are currently no guidelines regarding screening for OSA in the obese pregnant population, yet risks to both mother and foetus are well researched.

Obesity: a chronic relapsing progressive disease process. A position statement of the World Obesity Federation

This paper considers the argument for obesity as a chronic relapsing disease process. Obesity is viewed from an epidemiological model, with an agent affecting the host and producing disease. Food is the primary agent, particularly foods that are high in energy density such as fat, or in sugar-sweetened beverages. An abundance of food, low physical activity and several other environmental factors interact with the genetic susceptibility of the host to produce positive energy balance. The majority of this excess energy is stored as fat in enlarged, and often more numerous fat cells, but some lipid may infiltrate other organs such as the liver (ectopic fat). The enlarged fat cells and ectopic fat produce and secrete a variety of metabolic, hormonal and inflammatory products that produce damage in organs such as the arteries, heart, liver, muscle and pancreas. The magnitude of the obesity and its adverse effects in individuals may relate to the virulence or toxicity of the environment and its interaction with the host. Thus, obesity fits the epidemiological model of a disease process except that the toxic or pathological agent is food rather than a microbe. Reversing obesity will prevent most of its detrimental effects.

Role of incretin-based therapies and sodium-glucose co-transporter-2 inhibitors as adjuncts to insulin therapy in Type 2 diabetes, with special reference to IDegLira

The progressive nature of Type 2 diabetes necessitates treatment intensification over time in order to maintain glycaemic control, with many patients ultimately requiring insulin therapy. While insulin has unlimited potential efficacy, its initiation is often delayed and improvements in glycaemic control are typically accompanied by weight gain and an increased risk of hypoglycaemia, particularly as HbA1c approaches and falls below target levels. This may account for the sub-optimal control often achieved after insulin initiation. Combining insulin with antihyperglycaemic therapies that have a low risk of hypoglycaemia and are weight-neutral or result in weight loss is a therapeutic strategy with the potential to improve Type 2 diabetes management. Although the effects differ with each individual class of therapy, clinical trials have shown that adding a glucagon-like peptide-1 receptor agonist, dipeptidyl peptidase-4 inhibitor or sodium-glucose co-transporter-2 inhibitor to insulin regimens can offer a significant reduction in HbA1c without substantially increasing hypoglycaemia risk, or weight. The evidence and merit of each approach are reviewed in this paper. Once-daily co-formulations of a basal insulin and a glucagon-like peptide-1 receptor agonist have been developed (insulin degludec/liraglutide) or are under development (lixisenatide/insulin glargine). Insulin degludec/liraglutide phase III trials and a lixisenatide/insulin glargine phase II trial have shown robust HbA1c reductions, with weight loss and a low risk of hypoglycaemia. With insulin degludec/liraglutide now approved in Europe, an important consideration will be the types of patients who may benefit most from a fixed-ratio combination; this is discussed in the present review, and we also take a look toward future developments in the field.

Exposure-response analyses of liraglutide 3.0 mg for weight management

AIMS

Liraglutide 3.0 mg, an acylated GLP-1 analogue approved for weight management, lowers body weight through decreased energy intake. We conducted exposure-response analyses to provide important information on individual responses to given drug doses, reflecting inter-individual variations in drug metabolism, absorption and excretion.

METHODS

We report efficacy and safety responses across a wide range of exposure levels, using data from one phase II (liraglutide doses 1.2, 1.8, 2.4 and 3.0 mg), and two phase IIIa [SCALE Obesity and Prediabetes (3.0 mg); SCALE Diabetes (1.8; 3.0 mg)] randomized, placebo-controlled trials (n = 4372).

RESULTS

There was a clear exposure-weight loss response. Weight loss increased with greater exposure and appeared to level off at the highest exposures associated with liraglutide 3.0 mg in most individuals, but did not fully plateau in men. In individuals with overweight/obesity and comorbid type 2 diabetes, there was a clear exposure-glycated haemoglobin (HbA1c) relationship. HbA1c reduction increased with higher plasma liraglutide concentration (plateauing at ∼21 nM); however, for individuals with baseline HbA1c >8.5%, HbA1c reduction did not fully plateau. No exposure-response relationship was identified for any safety outcome, with the exception of gastrointestinal adverse events (AEs). Individuals with gallbladder AEs, acute pancreatitis or malignant/breast/benign colorectal neoplasms did not have higher liraglutide exposure compared with the overall population.

CONCLUSIONS

These analyses support the use of liraglutide 3.0 mg for weight management in all subgroups investigated; weight loss increased with higher drug exposure, with no concomitant deterioration in safety/tolerability besides previously known gastrointestinal side effects.

Energy balance and metabolic changes with sodium-glucose co-transporter 2 inhibition

Sodium-glucose co-transporter 2 (SGLT2) inhibitors are the latest addition to the class of oral glucose-lowering drugs. They have been rapidly adopted into clinical practice because of therapeutic advantages, including weight loss and reduction in blood pressure, in addition to glycaemic benefits and a low intrinsic risk of hypoglycaemia. Although there are extensive data on the clinical effects of SGLT2 inhibition, the metabolic effects of inhibiting renal glucose reabsorption have not been fully described. Recent studies have identified compensatory metabolic effects, such as an increase in endogenous glucose production, and have also shown an increase in glucagon secretion during SGLT2 inhibition. In addition, there is a discrepancy between the expected and observed weight loss found in clinical studies on SGLT2 inhibitors, probably as a result of changes in energy balance with this treatment approach. SGLT2 inhibition is likely to have intriguing effects on whole body metabolism which have not been fully elucidated, and which, if explained, might help optimize the use of this new class of medicines.

Fit for Birth - the effect of weight changes in obese pregnant women on maternal and neonatal outcomes: a pilot prospective cohort study

The 'Fit for Birth' study aimed to explore patterns of gestational weight gain and their relationship with pregnancy outcomes. The study had three aims: 1. To explore the feasibility of conducting a large cohort study in this setting. 2. To describe patterns of weight gain through pregnancy in obese women. 3. To explore associations of weight change during pregnancy with outcomes.

STUDY POPULATION

Pregnant women with a BMI ≥ 30 kg m(-2) at first antenatal clinic visit.

METHODS

This was a single centre pilot observational study based at the Liverpool Women's Hospital, a large UK maternity hospital.Women were recruited into the study at their antenatal booking visit and had weights measured throughout pregnancy. Patterns of weight gain were described and related to maternal and neonatal outcomes.

MAIN OUTCOME MEASURE

The primary outcome was a composite measure consisting of any of 12 adverse maternal and foetal outcomes. This was compared by categorized pregnancy weight gain (<0 kg, 0-5 kg, 5.1-9 kg and >9 kg).

RESULTS

Eight hundred and twenty four women consented to participation between June 2009 and June 2010. Weight data were collected on 756 women. Only 385 women had weights measured in all three study assessment periods (6-20 weeks, 20 + 1 to 32 weeks and >32 weeks gestation) while 427 women had weights measured in period 3. Individual patterns of weight gain varied widely and missing data were common and non-random. There was a significant association between increased weight gain during pregnancy and poor maternal and foetal outcome.

CONCLUSIONS

Weight gain in obese women during pregnancy can be highly variable. Our study supports an association between increased weight gain in pregnancy and adverse perinatal outcomes.

Impact of bariatric surgery on physical functioning in obese adults

Obesity is associated with a profound impairment in the ability to perform the basic physical activities required for everyday function. This impacts on quality of life and contributes to disability. Bariatric surgery leads to weight loss and metabolic improvements in severe obesity; however, less is known about its effect on physical functioning. This narrative review summarizes current evidence on the effect of bariatric surgery on this outcome with a consideration of the mechanisms involved. Nine longitudinal observational studies reporting objective measures of physical functioning were identified. Inclusion criteria, follow-up time and outcomes reported varied considerably between studies and sample sizes were small. They all showed a significant improvement in performance following surgery despite variations in baseline patient characteristics. Additionally, six studies were found in which subjects were subjected to exercise testing protocols. Performance of the test protocol improved in all. Where reported, peak oxygen uptake related to body weight improved; however, absolute values were either unchanged or decreased. In conclusion, observational evidence suggests that patients' physical functioning improves following bariatric surgery. More evidence is required regarding mechanisms involved; however, it may be due to improved efficiency in performing activities as opposed to absolute improvements in cardiorespiratory or muscle function.

The importance of weight management in type 2 diabetes mellitus

BACKGROUND

The obesity epidemic is driving the increased prevalence of type 2 diabetes mellitus (T2DM), and the vast majority of patients with T2DM are overweight or obese. Excess body weight is associated with the risk of cardiometabolic complications, which are major causes of morbidity and mortality in T2DM.

AIMS

To review evidence about effects of weight loss in pre-diabetes and established T2DM.

RESULTS

In prediabetes, weight loss has been shown to delay the onset or decrease the risk of T2DM, while in established T2DM weight loss has been shown to improve glycaemic control, with severe calorie restriction even reversing the progression of T2DM. Observational studies support the reduction in cardiovascular risk factors following weight loss in patients with T2DM. However, data from the randomised Look AHEAD trial revealed intensive weight loss interventions did not reduce the rate of cardiovascular events in overweight or obese adults with T2DM, and secondary analyses of other large cardiovascular outcomes trials have also been inconclusive. However, besides cardiovascular risk, other documented benefits of weight loss in T2DM include improvements in quality of life, mobility, and physical and sexual function.

CONCLUSIONS

Physicians should encourage weight loss in all overweight patients with or at risk of T2DM, and should consider the impact on weight when choosing the most appropriate glucose-lowering therapies for these patients.

Characteristics and perspectives of night-eating behaviour in a severely obese population

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Night-eating syndrome (NES) can be a feature of severe obesity. NES is a dysfunction of circadian rhythm and is associated with impaired sleep.

WHAT THIS STUDY ADDS

Night eaters with severe obesity are more likely to be low in mood and unemployed compared with non-night eaters. Night eaters with severe obesity describe compulsive and uncontrolled eating. Research interest in night-eating syndrome (NES) has grown in recent years in line with increased rates of obesity. This study used a mixed-methods approach to investigate its characteristics in severe obesity. Eighty-one individuals (mean [standard deviation] age 44.6 [11.6] years, [body mass index] 50.0 [10.7] kg m(-2) ; 43% men) from a hospital-based UK obesity clinic were interviewed for NES based on 2003 criteria. Full and partial NES were combined into one night-eating behaviour (NEB) group (n = 31). Demographic and clinical characteristics were compared with those of non-NEB individuals (n = 50). NEB characteristics were also identified through exploratory thematic analysis of interview data. NEB individuals had lower mood (P = 0.01) and were less likely to be employed (P = 0.03). Differences in mean age and reported sleep duration were not significant. Thematic analysis of patient perceptions of NEB highlighted the potential heterogeneity of NEB development: NEB developed in childhood, adolescence and adulthood. Individuals reported long-standing and current sleep difficulties, negative affect and conflictful relationships. Night eating was solitary, compulsive and uncontrolled, and daytime eating patterns were chaotic. Accounts of awareness of night eating were conflicting. Severely obese night eaters are characterized by low mood and lack of employment. Further studies are required to explore behavioural and cognitive influences on night eating in severe obesity.

Dapagliflozin in patients with type 2 diabetes receiving high doses of insulin: efficacy and safety over 2 years

AIMS

Dapagliflozin, a selective inhibitor of sodium-glucose cotransporter 2 (SGLT2), has been shown to improve glycaemic control, stabilize insulin dosing and mitigate insulin-associated weight gain over 48 weeks in patients whose type 2 diabetes mellitus (T2DM) was inadequately controlled despite high doses of insulin. Here the efficacy and safety of dapagliflozin therapy after a total of 104 weeks are evaluated in this population.

METHODS

This was a 24-week, randomized, placebo-controlled, double-blinded, multicentre trial followed by two site- and patient-blinded extension periods of 24 and 56 weeks (NCT00673231), respectively. A total of 808 patients, whose T2DM was inadequately controlled on insulin ≥30 IU/day, with or without up to two oral antidiabetic drugs, were randomly assigned to receive placebo or 2.5, 5 or 10 mg/day of dapagliflozin for 104 weeks. At 48 weeks, patients on dapagliflozin 5 mg were switched to 10 mg. Outcomes over 104 weeks included change from baseline in HbA1c, insulin dose and body weight; analyses used observed cases and included data after insulin up-titration. Adverse events (AEs) were evaluated throughout 104 weeks.

RESULTS

Five hundred and thirteen patients (63.6%) completed the study. Mean HbA1c changes from baseline at 104 weeks were -0.4% in the placebo group and -0.6 to -0.8% in the dapagliflozin groups. In the placebo group, mean insulin dose increased by 18.3 IU/day and weight increased by 1.8 kg at 104 weeks, whereas in the dapagliflozin groups, insulin dose was stable and weight decreased by 0.9-1.4 kg. AEs, including hypoglycaemia, were balanced across groups. Proportions of patients with events suggestive of genital infection and of urinary tract infection (UTI) were higher with dapagliflozin versus placebo (genital infection 7.4-14.3% vs. 3.0%; UTI 8.4-13.8% vs. 5.6%) but most occurred in the first 24 weeks and most were single episodes that responded to routine management.

CONCLUSIONS

Dapagliflozin improved glycaemic control, stabilized insulin dosing and reduced weight without increasing major hypoglycaemic episodes over 104 weeks in patients whose T2DM was inadequately controlled on insulin. However, rates of genital infection and of UTI were elevated with dapagliflozin therapy.

Efficacy and safety of canagliflozin in patients with type 2 diabetes mellitus inadequately controlled with metformin and sulphonylurea: a randomised trial

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor developed for the treatment of type 2 diabetes mellitus (T2DM). This randomised, double-blind, placebo-controlled, Phase 3 study evaluated the efficacy and safety of canagliflozin as an add-on to metformin plus sulphonylurea in patients with T2DM.

METHODS

Patients (N = 469) received canagliflozin 100 or 300 mg or placebo once daily during a 26-week core period and a 26-week extension. Prespecified primary end-point was change in HbA1c at 26 weeks. Secondary end-points included change in HbA1c at week 52 as well as proportion of patients achieving HbA1c < 7.0%, change in fasting plasma glucose (FPG) and systolic blood pressure, and per cent change in body weight, high-density lipoprotein cholesterol, and triglycerides (weeks 26 and 52).

RESULTS

HbA1c was significantly reduced with canagliflozin 100 and 300 mg vs. placebo at week 26 (-0.85%, -1.06%, and -0.13%; p < 0.001); these reductions were maintained at week 52 (-0.74%, -0.96%, and 0.01%). Both canagliflozin doses reduced FPG and body weight vs. placebo at week 26 (p < 0.001) and week 52. Overall adverse event (AE) rates were similar across groups over 52 weeks, with higher rates of genital mycotic infections and osmotic diuresis-related AEs seen with canagliflozin vs. placebo; these led to few discontinuations. Increased incidence of documented, but not severe, hypoglycaemia episodes was seen with canagliflozin vs. placebo.

CONCLUSIONS

Canagliflozin improved glycaemic control, reduced body weight, and was generally well tolerated in T2DM patients on metformin plus sulphonylurea over 52 weeks.

Dose-ranging study with the glucokinase activator AZD1656 in patients with type 2 diabetes mellitus on metformin

AIM

To investigate the effect of glucokinase activator AZD1656 on glycated haemoglobin (HbA1c) as an add-on to metformin in patients with type 2 diabetes.

METHODS

This randomized, double-blind, placebo-controlled study (NCT01020123) was conducted over 4 months with an optional 2-month extension. Patients (n = 458) with HbA1c 7.5-10% were randomized to AZD1656 20 mg (n = 40) or 40 mg (n = 52) fixed doses or 10-140 mg (n = 91) or 20-200 mg (n = 93) titrated doses, placebo (n = 88) or glipizide 5-20 mg titrated (n = 94). Patients (n = 72) with HbA1c >10 and ≤12% received open-label AZD1656 (20-200 mg titrated). Primary outcome was placebo-corrected change in HbA1c from baseline to 4 months of treatment.

RESULTS

Significant reductions in HbA1c from baseline to 4 months were observed with blinded AZD1656 10-140 and 20-200 mg versus placebo [mean (95% CI) changes: -0.80 (-1.14; -0.46) and -0.81 (-1.14; -0.47) %, respectively), with similar reductions observed with glipizide. A higher percentage of patients on AZD1656 than on placebo achieved HbA1c ≤7.0 or ≤6.5 % after 4 months. Mean (s.d.) change in HbA1c for open-label AZD1656 (20-200 mg) was -2.8 (1.19) % after 4 months. AZD1656 was well tolerated, with less hypoglycaemia than glipizide. In the extension population, HbA1c was still reduced with AZD1656 versus placebo after 6 months, but the effect of AZD1656 on glucose control was not sustained over time.

CONCLUSION

Addition of AZD1656 (individually titrated) to metformin gave significant improvements in glycaemic control up to 4 months, although efficacy diminished over time.

Efficacy and safety of ipragliflozin in patients with type 2 diabetes inadequately controlled on metformin: a dose-finding study

AIMS

Ipragliflozin is a novel, selective inhibitor of sodium glucose co-transporter 2 (SGLT2 inhibitor) in clinical development for type 2 diabetes mellitus (T2DM) treatment. This study assessed the efficacy and safety of different doses of ipragliflozin.

METHODS

In a 12-week, multicentre, double-blind, randomized, placebo-controlled, dose-finding study patients with inadequate glycaemic control on metformin monotherapy (≥1500 mg/day) were randomized to one of four ipragliflozin treatment groups (12.5, 50, 150 or 300 mg once daily) or placebo. Primary efficacy outcome was mean change from baseline in haemoglobin A1c (HbA1c) compared to placebo at week 12. Adverse events (AEs), vital signs and laboratory safety measurements were assessed.

RESULTS

Ipragliflozin dose dependently decreased HbA1c from baseline to week 12 compared to placebo (-0.22, -0.34, -0.40 and -0.48% for ipragliflozin 12.5, 50, 150 and 300 mg, respectively). Decreases in body weight and blood pressure were observed for all ipragliflozin groups. AEs occurred in 39.7-51.4% of the ipragliflozin groups and 39.4% of placebo patients. Urinary tract infections (1.4-6.9 vs. 6.1%), genital infections (0-4.3 vs. 1.5%) and hypoglycaemia (0-5.9 vs. 3.0%) were similar in the ipragliflozin and placebo groups, respectively, without dose dependency. There were no clinically relevant effects on other safety measurements.

CONCLUSIONS

Ipragliflozin treatment improved glycaemic control when added to metformin therapy and may be associated with weight loss and reductions in blood pressure compared to placebo. No safety or tolerability concerns were identified at any of the tested doses supporting the further development of ipragliflozin at ≥50 mg doses in T2DM patients.

[Long-term efficacy of dapagliflozin in patients with type 2 diabetes mellitus receiving high doses of insulin]

BACKGROUND

Dapagliflozin, a selective inhibitor of sodium-glucose cotransporter 2, may improve glycemic control with a lower dose of insulin and attenuate the associated weight gain in patients with inadequate control despite high doses of insulin.

OBJECTIVE

To evaluate the efficacy and safety of adding dapagliflozin therapy in patients whose type 2 diabetes mellitus is inadequately controlled with insulin with or without oral antidiabetic drugs.

DESIGN

A 24-week, randomized, placebo-controlled, multicenter trial followed by a 24-week extension period. An additional 56-week extension period is ongoing. (ClinicalTrials.gov registration number: NCT00673231).

SETTING

126 centers in Europe and North America from 30 April 2008 to 19 November 2009.

PATIENTS

808 patients with inadequately controlled type 2 diabetes mellitus receiving at least 30 U of insulin daily, with or without up to 2 oral antidiabetic drugs.

INTERVENTION

Patients were randomly assigned in a 1:1:1:1 ratio and allocated with a computer-generated scheme to receive placebo or 2.5, 5, or 10 mg of dapagliflozin, once daily, for 48 weeks.

MEASUREMENTS

The primary outcome was change in hemoglobin A1c from baseline to 24 weeks. Secondary outcomes included changes in body weight, insulin dose, and fasting plasma glucose level at 24 weeks and during the 24-week extension period. Adverse events were evaluated throughout both 24-week periods.

RESULTS

800 patients were analyzed. After 24 weeks, mean hemoglobin A1c decreased by 0.79 % to 0.96 % with dapagliflozin compared with 0.39 % with placebo (mean difference, -0.40 % [95 % CI, -0.54 % to -0.25 %] in the 2.5-mg group, -0.49 % [CI, -0.65 % to -0.34 %] in the 5-mg group, and -0.57 % [CI, -0.72 % to -0.42 %] in the 10-mg group). Daily insulin dose decreased by 0.63 to 1.95 U with dapagliflozin and increased by 5.65 U with placebo (mean difference, -7.60 U [CI, -10.32 to -4.87 U] in the 2.5-mg group, -6.28 U [CI, -8.99 to -3.58 U] in the 5-mg group, and -6.82 U [CI, -9.56 to -4.09 U] in the 10-mg group). Body weight decreased by 0.92 to 1.61 kg with dapagliflozin and increased by 0.43 kg with placebo (mean differences, -1.35 kg [CI, -1.90 to -0.80 kg] in the 2.5-mg group, -1.42 kg [CI, -1.97 to -0.88 kg] in the 5-mg group, and -2.04 kg [CI, -2.59 to -1.48 kg] in the 10-mg group). These effects were maintained at 48 weeks. Compared with the placebo group, patients in the pooled dapagliflozin groups had a higher rate of hypoglycemic episodes (56.6 % vs. 51.8 %), events suggesting genital infection (9.0 % vs. 2.5 %), and events suggesting urinary tract infection (9.7 % vs. 5.1 %).

LIMITATION

Insulin doses were not titrated to target, and the study was not designed to evaluate long-term safety.

CONCLUSION

Dapagliflozin improves glycemic control, stabilizes insulin dosing, and reduces weight without increasing major hypoglycemic episodes in patients with inadequately controlled type 2 diabetes mellitus.

PPAR agonists for the treatment of cardiovascular disease in patients with diabetes

Diabetes is a complex disease defined by hyperglycaemia; however, strong associations with abdominal obesity, hypertension and dyslipidaemia contribute to the high risk of cardiovascular disease. Although aggressive glycaemic control reduces microvascular complications, the evidence for macrovascular complications is less certain. The theoretical benefits of the mode of action of peroxisome proliferator-activated receptor (PPAR) agonists are clear. In clinical practice, PPAR-α agonists such as fibrates improve dyslipidaemia, while PPAR-γ agonists such as thiazolidinediones improve insulin resistance and diabetes control. However, although these agents are traditionally classed according to their target, they have different and sometimes conflicting clinical benefit and adverse event profiles. It is speculated that this is because of differing properties and specificities for the PPAR receptors (each of which targets specific genes). This is most obvious in the impact on cardiovascular outcomes--in clinical trials pioglitazone appeared to reduce cardiovascular events, whereas rosiglitazone potentially increased the risk of myocardial infarction. The development of a dual PPAR-α/γ agonist may prove beneficial in effectively managing glycaemic control and improving dyslipidaemia in patients with type 2 diabetes. Yet, development of agents such as muraglitazar and tesaglitazar has been hindered by various serious adverse events. Aleglitazar, a balanced dual PPAR-α/γ agonist, is currently the most advanced in clinical development and has shown promising results in phase II clinical trials with beneficial effects on glucose and lipid variables. A phase III study, ALECARDIO, is ongoing and will establish whether improvements in laboratory test profiles translate into an improvement in cardiovascular outcomes.

Night eating syndrome: implications for severe obesity

Night eating syndrome (NES) was first identified in 1955 by Stunkard, a psychiatrist specialising in eating disorders (ED). Over the last 20 years considerable progress has been made in defining NES as a significant clinical entity in its own right and it has now been accepted for inclusion in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) due for publication in 2013. NES is considered a dysfunction of circadian rhythm with a disassociation between eating and sleeping. Core criteria include a daily pattern of eating with a significantly increased intake in the evening and/or night time, as manifested by one or both of the following: at least 25% of food intake is consumed after the evening meal or at least two episodes of nocturnal eating per week. An important recent addition to core criteria includes the presence of significant distress and/or impairment in functioning. Stunkard's team recommend further investigation on the pathogenesis of NES, in particular its relationship with traumatic life events, psychiatric comorbidity, the age of onset of NES and course of NES over time. The relationship between NES and other ED also requires further clarification as night-eaters exhibit some features of other ED; previous guidance to separate NES from other ED may have hindered earlier characterisation of NES. Evidence from European and American studies suggests NES features strongly in populations with severe obesity. The complex interplay between depression, impaired sleep and obesity-related comorbidity in severely obese individuals makes understanding NES in this context even more difficult. This review examines evidence to date on the characterisation of NES and concludes by examining the applicability of current NES criteria to individuals with severe obesity.

Ghrelin does not orchestrate the metabolic changes seen in fasting but has significant effects on lipid mobilisation and substrate utilisation

OBJECTIVE

Short-term fasting is associated with increased GH pulsatility and mobilisation of fats, but underlying mechanisms are unclear. We studied ghrelin's role during fasting and the effects of exogenous ghrelin on lipid mobilisation.

DESIGN

Randomised placebo-controlled study.

METHODS

In this study, ten controls (body mass index (BMI) 23.3±3.2), ten morbidly obese subjects (BMI 50.1±10.6) and six post-gastrectomy subjects (BMI 25.2±1.0) were fasted for 36  h undergoing regular blood sampling. On a separate occasion, subjects were infused with either i.v. ghrelin (5  pmol/kg per min) or saline over 270  min.

RESULTS

Obese and post-gastrectomy subjects had lower ghrelin compared with controls (ANOVA, P=0.02) during the fast. Controls and gastrectomy subjects showed a similar increase in GH pulsatility, circulating non-esterified fatty acids (NEFA) and 3β-hydroxybutyrate (3 HB). Obese subjects had an impaired GH response (P<0.001), reduced excursions of 3 HB (P=0.01) but no change in NEFA excursions (P=0.09) compared with controls. Ghrelin infusion increased GH, NEFA and ketone bodies (ANOVA, P<0.0001) in all the three groups, but GH response was impaired in the obese subjects (P=0.001). Ghrelin also induced a significant (ANOVA, P=0.004) biphasic NEFA response to meals in all the subjects.

CONCLUSIONS

Despite low circulating ghrelin, gastrectomy subjects maintain a normal metabolic response to fasting, implying that ghrelin plays a minimal role. In contrast, infused ghrelin has significant effects on lipid mobilisation and induces a marked biphasic NEFA response to meals. Hence, ghrelin may play a significant role in meal-related substrate utilisation and metabolic flexibility.

The four-variable modification of diet in renal disease formula underestimates glomerular filtration rate in obese type 2 diabetic individuals with chronic kidney disease

AIMS/HYPOTHESIS

GFR is commonly estimated using the four-variable Modification of Diet in Renal Disease (MDRD) formula and this forms the basis for classification of chronic kidney disease (CKD). We investigated the effect of obesity on the estimation of glomerular filtration rate in type 2 diabetic participants with CKD.

METHODS

We enrolled 111 patients with type 2 diabetes mellitus in different stages of CKD. GFR was measured using (51)Cr-labelled EDTA plasma clearance and was estimated using the four-variable MDRD formula.

RESULTS

The bias between estimated and measured GFR was -22.4 (-33.8 to -11.0) p < 0.001 in the obese group compared with -6.04 (-17.6 to -5.5) p = 0.299 in the non-obese group. When GFR was indexed to body surface area of 1.73 m(2), the bias remained significant at -9.4 (-13.4 to -5.4) p < 0.001 in the obese participants.

CONCLUSIONS/INTERPRETATION

This study suggests that the four-variable MDRD formula significantly underestimates GFR in obese type 2 diabetic participants with CKD.

Ghrelin inhibits autonomic function in healthy controls, but has no effect on obese and vagotomized subjects

OBJECTIVE

Ghrelin inhibits sympathetic nervous system (SNS) activity in rodents. We studied the effect of ghrelin on healthy humans, in obesity and in vagotomized subjects.

DESIGN

Randomized, double-blinded, placebo-controlled crossover.

SUBJECTS

Seven lean [mean body mass index (BMI) 23·6 ± 0·9 kg/m(2) ], seven morbidly obese (mean BMI 50·9 ± 4·4 kg/m(2) ) and seven post-gastrectomy subjects (mean BMI 22·0 ± 1·1 kg/m(2) ).

MEASUREMENTS

Subjects were randomized to intravenous ghrelin (5 pmol/kg/min) or saline over 270 min. Subjects had a fixed calorie meal and a free choice buffet during the infusion. Heart rate variability (HRV) was measured. Total power (TP) represents overall autonomic function, low-frequency (LF) power represents sympathetic and parasympathetic activity, and high-frequency (HF) power represents parasympathetic activity. Very low (VLO) frequency represents the frequency band associated with thermogenesis.

RESULTS

Preliminary anova analysis, looking at all three subject groups together, showed that ghrelin had an overall highly significant inhibitory effect on TP (P = 0·001), HF power (P = 0·04), VLO power (P = 0·03) and no effect on LF (P = 0·07). Further subset analysis revealed that ghrelin had a significant effect on TP (P = 0·03), borderline effect on LF power (P = 0·06) and no effect on HF power (P = 0·1) in healthy controls. By contrast in obese subjects, ghrelin had no effect on TP (P = 0·3), LF (P = 0·5) and HF (P = 0·06) and also no effect in the vagotomized subjects on TP (P = 0·7), LF (P = 0·7) and HF (P = 0·9). Ghrelin had no effect on the LF/HF ratio.

CONCLUSIONS

Ghrelin inhibits SNS activity in healthy controls with a moderate effect on parasympathetic nervous system activity but had no effect on obese subjects. Vagotomized subjects also did not respond to ghrelin, suggesting the vagus nerve is important for the effects of peripheral ghrelin on the SNS.

In humans the adiponectin receptor R2 is expressed predominantly in adipose tissue and linked to the adipose tissue expression of MMIF-1

In this study, the regional adipose tissue-adiponectin (AT-ADN) and adiponectin receptor (R1 and R2) expression and their relation with metabolic parameters, circulating and AT-derived cytokine expressions were compared. Paired subcutaneous adipose tissue (SCAT) and visceral adipose tissue (VAT) were taken from 18 lean and 39 obese humans, AT-mRNA expression of adipokines analysed by RT-PCR and corresponding serum levels by enzyme-linked immunosorbent assay (ELISA). R1 and R2 adipocyte expression was compared with 17 other human tissues. ADN-gene expression was lower in VAT than SCAT [mean (SD) 1.54 (1.1) vs. 2.84 (0.87); p < 0.001], and lower in obese subjects (VAT : p = 0.01;SCAT : p < 0.001). SCAT-ADN correlated positively with serum ADN (r = 0.33;p = 0.036) but not VAT-ADN. AT expressions of ADN and macrophage migration inhibiting factor (MMIF), IL18 and cluster of differentiation factor 14 (CD14) in both depots showed inverse correlations. R1 and R2 were expressed ubiquitously and R2 highest in SCAT, and this is much higher (x100) than R1 (x100). R expression was similar in lean and obese subjects and unrelated to the metabolic syndrome, however, receptors correlated with VAT-MMIF (R 1: r = 0.4;p = 0.008;R 2: r = 0.35,p = 0.02) and SCAT-MMIF expression (R 2: r = 0.43;p = 0.004). Unlike ADN, its receptors are expressed in many human tissues. Human R2 expression is not highest in the liver but in AT where it is associated with MMIF expression. The adiponectin-dependent insulin-sensitizing action of thiazolidinediones is thus probably to differ amongst species with weaker effects on the human liver.

The effects of sibutramine on the microstructure of eating behaviour and energy expenditure in obese women

Given the suggestion that many potential anti-obesity drugs may enhance within-meal satiation, few studies have directly measured the effects of any drug on the microstructure of human eating behaviour. The effects of 7 days dosing with sibutramine 10 mg and 15 mg a day on appetite and energy balance were determined in 30 obese women (BMI 34.6 +/- 3.3 kg/m2, age 46.0 +/- 12.9 years) using a Universal Eating Monitor (UEM) and indirect calorimetry, in a double-blind, placebo-controlled crossover study. At day 7, sibutramine 10 mg and 15 mg reduced food intake by 16.6% and 22.3%, respectively (p < 0.001), compared with placebo. Sibutramine reduced eating rate compared with placebo rather than meal length (10 mg p < 0.05; 15 mg p < 0.001). In addition, sibutramine 10 mg significantly reduced hunger later in the meal (p < 0.05) and sibutramine 15 mg increased fullness early in the meal (p < 0.01), both of which are consistent with enhanced within-meal satiation. Sibutramine had little effect on resting metabolic rate, although 15 mg did significantly reduce respiratory quotient at several time points during the test day. These results provide novel evidence that decreased consumption of a test meal induced by sibutramine is primarily because of reduced eating rate, enhancing the deceleration in cumulative food intake within a meal associated with the development of satiety. Changes in within-meal appetite ratings appear particularly sensitive to drug-induced enhancement of satiation, and may provide key indices for assessing the therapeutic potential of novel anti-obesity drugs.

Effects of peripheral administration of synthetic human glucose-dependent insulinotropic peptide (GIP) on energy expenditure and subjective appetite sensations in healthy normal weight subjects and obese patients with type 2 diabetes

BACKGROUND

Apart from their role in insulin secretion and glucose homeostasis, the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) exert a number of extra-pancreatic effects which in the case of GIP remain largely unknown.

DESIGN/PATIENTS

Six obese male patients with diet-controlled type 2 diabetes (T2DM) and six healthy lean male subjects were studied. The protocol included four experiments for each participant that were carried out in randomized order and included: GLP-1 infusion at a rate of 1 pmol/kg/min for 4 h, GIP at a rate of 2 pmol/kg/min, GLP-1 (at 1 pmol/kg/min) with GIP (at 2 pmol/kg/min), and placebo infusion for 4 h. Energy expenditure (EE) was measured throughout with indirect calorimetry and subjects were given a series of visual analogue scales to rate hourly their hunger, fullness, urge to eat and prospective consumption of food. Immediately following termination of the infusions all subjects were offered a free choice buffet lunch and total calorie and macronutrient intake was calculated.

RESULTS

During GIP infusion there was a trend for healthy subjects to report higher hunger scores and a reduction in EE only when compared with placebo. These parameters remained unchanged in patients with T2DM. Ad libitum energy intake after all four infusions was the same in both groups.

CONCLUSION

We report here for the first time that GIP infusion may impact on resting EE and subjective appetite sensations in normal weight healthy subjects and further studies with larger numbers of subjects are required to help define more conclusively the precise role of GIP in energy balance in humans.

Growth hormone and changes in energy balance in growth hormone deficient adults

BACKGROUND

Adults with growth hormone deficiency (AGHD) have an adverse body composition with an increased prevalence of obesity. It is not known whether growth hormone replacement (GHR) results in alterations in energy intake (EI) and/or energy expenditure (EE). The aim of the study was to investigate the effects of GHR on EI and EE.

MATERIALS AND METHODS

Nineteen hypopituitary adults (14 males, 5 females, mean age 46.2 years) with severe GHD (peak GH response to glucagon <or= 9 mU L(-1)) were studied. All patients self-injected recombinant human GH starting with 0.3 mg s.c. daily. The following were measured before and following 6 months of stable maintenance of GHR: food intake during a test meal, appetite ratings, resting EE (indirect calorimetry) and voluntary physical activity (accelerometry).

RESULTS

GHR nearly doubled voluntary physical activity (mean activity units 3319 vs. 1881, P = 0.007) and improved quality of life score (mean score 9.1 vs. 16.5, P < 0.0001). Subjects reported higher fasting hunger ratings (mean 64.8 vs. 49.6, P = 0.02) but ad libitum energy intake remained unchanged. Eating behavioural traits were favourably altered with lower disinhibition (mean 6.0 vs. 7.2, P = 0.02) and lower susceptibility to hunger ratings (4.6 vs. 6.8, P = 0.001) after GHR. Additionally, GHR did not result in significant changes in resting EE, body weight and body mass index.

CONCLUSIONS

GHR in AGHD significantly improves voluntary physical activity and quality of life. Following GHR, subjects experience greater 'state' (physiological) hunger, reductions in eating disinhibition and hunger susceptibility, but no effects on calorie intake or macronutrient choice were detected.

Energy restriction enhances therapeutic efficacy of the PPARgamma agonist, rosiglitazone, through regulation of visceral fat gene expression

AIM

Consumption of a palatable diet can induce hyperphagia, leading to weight gain (dietary obesity) and insulin resistance in rats. Thiazolidinediones (TZDs) can also induce hyperphagia in rats but conversely have an insulin-sensitizing effect. The aim of this study was to investigate whether preventing TZD-induced hyperphagia (i.e. energy restriction) in dietary obese (DIO) rats would enhance the insulin-sensitizing effects of treatment at a therapeutic dose; and, within this paradigm, to produce an original survey of candidate TZD-gene targets in the clinically relevant visceral white adipose tissue (WAT) depot.

METHODS

DIO rats that were either freely fed or energy restricted (i.e. pair-fed to the level of untreated controls) were treated with rosiglitazone maleate (RSG; 3 mg/kg/day) for 2 weeks, the restricted group controlling for treatment-induced hyperphagia and weight gain. The outcome measures were circulating concentrations of various biochemical markers of insulin resistance, and gene expression was measured in epididymal WAT.

RESULTS

In both freely fed and pair-fed groups, compared to untreated DIO controls, RSG reduced plasma levels of insulin (-29% and -43%; p < 0.05 and p < 0.001, respectively), free fatty acids (FFAs; -45% and -48%; p < 0.01 and p < 0.001, respectively) and triglycerides (TGs; -63% and -72%; both p < 0.001), reflected in improved insulin sensitivity, as measured by homeostasis model assessment (-29% and -43%; p < 0.01 and p < 0.0001). RSG also increased the expression of the fatty acid transport/synthesis genes, fatty acid transport protein (2.4-3.2-fold), epidermal fatty acid-binding protein (FABP; 1.7-2.0-fold), heart FABP (25-29-fold) and fatty acid synthase (2.3-2.9-fold; all p < 0.05) in both groups. Adipocyte FABP was also increased by RSG treatment, but only in combination with energy restriction (1.52-fold; p < 0.05) as was hexokinase II expression (p < 0.001). In contrast, the drug had no effect on expression of several genes associated with lipolysis. Although obesity-induced hyperleptinaemia was normalized only in the energy-restricted group, leptin messenger RNA (mRNA) expression was reduced in both treated groups (all p < 0.01). Resistin and tumour necrosis factor-alpha expression was also reduced, though in the latter case, only with energy restriction (p < 0.05). Other adipokines were unaffected by RSG treatment.

CONCLUSION

Our results clearly show that energy restriction enhances the therapeutic efficacy of TZDs and suggest that this occurs, at least in part, through a modulatory effect on gene expression in visceral WAT. These findings improve our understanding of the underlying mechanistic basis for the clinical usefulness of dietary restriction as an adjunct to TZD therapy in type 2 diabetes.

The importance of free fatty acids in the development of Type 2 diabetes

The recent increase in the prevalence of obesity has been associated with a coincident rise in the prevalence of Type 2 diabetes, whereas weight loss has been shown to decrease the risk of Type 2 diabetes. The pathophysiological mechanisms that have been proposed to explain this link are fundamentally concerned with insulin resistance and the decline in pancreatic B-cell function that accompanies an increase in visceral obesity. They involve the rise in the plasma concentrations of free fatty acids (FFAs) that are associated with an increase in fat mass. Elevated levels of FFAs can lead to insulin resistance, and evidence is growing that B-cell function is impaired through lipotoxicity. Factors such as tumour necrosis factor-alpha (TNF-alpha) and adiponectin, released from adipose tissue, can also modulate insulin resistance. Many interventions that are helpful in treating or preventing Type 2 diabetes, such as weight loss and certain pharmacological interventions, reduce circulating FFA concentrations to a greater or lesser extent. Recent study results suggest that peroxisome proliferator-activated receptor (PPAR)gamma agonists have an effect on the development of Type 2 diabetes. However, in light of concerns over the apparent increase in congestive heart failure with PPARgamma agonists, their place in the prevention of Type 2 diabetes remains to be determined.

Lack of an acute effect of ghrelin on markers of bone turnover in healthy controls and post-gastrectomy subjects

BACKGROUND

Ghrelin is a gut-brain peptide that powerfully stimulates appetite and growth hormone secretion and is also known to directly regulate osteoblast cell function in vitro and in animal models. Little is known about the effects of ghrelin on bone turnover in humans. As the stomach is the main site of ghrelin synthesis, gastrectomy patients are deficient in ghrelin; they are also prone to osteopenia and osteomalacia.

HYPOTHESIS

Ghrelin may play a role in bone regulation in humans; ghrelin deficiency following gastrectomy is associated with the disrupted regulation of bone turnover seen in these subjects.

SUBJECTS AND METHODS

In a randomised, double-blind, placebo-controlled study 8 healthy controls and 8 post-gastrectomy subjects were infused with intravenous ghrelin (5 pmol/kg/min) or saline over 240 min on different days. Subjects were given a fixed energy meal during the infusion. Ghrelin, GH, type-1 collagen beta C-telopeptide (betaCTX), a marker of bone resorption, and procollagen type-1 amino-terminal propeptide (P1NP), a marker of bone formation, were measured.

RESULTS

Fasting ghrelin was significantly lower in the gastrectomy group during the saline infusion (226.1+/-62.0 vs. 762+/-71.1 ng/l p<0.001). Growth hormone was significantly higher at 90 min after the ghrelin infusion, compared to saline in both healthy controls (61.1+/-8.8 vs. 1.4+/-0.6 mIU/l p<0.001) and gastrectomy subjects (61.1+/-11.8 vs. 0.9+/-0.2 mIU/l p<0.001) confirming the ghrelin was bioactive. Gastrectomy subjects were significantly older and had significantly higher plasma betaCTX than healthy controls at all time points (ANOVA p=0.009). After adjustment for age and BMI ghrelin was found to be a significant predictor of baseline plasma betaCTX and was inversely correlated with baseline plasma betaCTX (beta=-0.54 p=0.03 R2=26%). However, there was no significant effect of the ghrelin infusion on plasma betaCTX or P1NP in either subject group.

CONCLUSIONS

Ghrelin infusion has no acute effect on markers of bone turnover in healthy controls and post-gastrectomy subjects, but is inversely correlated with bone resorption.

Plasma obestatin levels are lower in obese and post-gastrectomy subjects, but do not change in response to a meal

OBJECTIVE

To investigate a potential role for obestatin in humans by examining response to a fixed energy meal.

CONTEXT

A new anorectic peptide hormone, obestatin has recently been isolated from rat stomach. The significance of this peptide in humans is unknown.

STUDY DESIGN

Case-control study.

SETTING

Hospital-based study.

PATIENTS

Nine healthy controls, nine morbidly obese subjects and eight post-gastrectomy subjects.

INTERVENTION

Subjects attended after an overnight fast and were given a fixed energy meal (1550 kJ).

MAIN OUTCOME MEASURE

The response of obestatin to a meal in the different groups.

RESULTS

Fasting obestatin was significantly lower in obese subjects as compared to lean subjects (27.8+/-4 vs 17.2+/-2 pg/ml, P=0.03). Obestatin was also decreased in gastrectomy subjects but this did not reach statistical significance (27.8+/-4 vs 21.9+/-3 pg/ml, P=0.3). Obestatin did not change significantly from baseline in response to the meal. Lean and obese subjects had a similar obestatin/ghrelin ratio (0.04+/-0.003 vs 0.05+/-0.009, P=0.32), but this was higher in the gastrectomy group (0.04+/-0.003 vs 0.1+/-0.01, P<0.001).

CONCLUSIONS

Obestatin does not vary significantly with a fixed energy meal, but is significantly lower in morbidly obese subjects as compared to lean subjects supporting a possible role for obestatin in long-term body weight regulation. Obestatin tended to be lower in gastrectomy subjects and their obestatin/ghrelin ratio differed from healthy controls. Hence, the expression of obestatin is altered following gastrectomy, suggesting other sites outside the stomach may also secrete obestatin.

Effects of olanzapine in male rats: enhanced adiposity in the absence of hyperphagia, weight gain or metabolic abnormalities

Many of olanzapine's (OLZ) actions in humans related to weight regulation can be modelled in female rats (Cooper et al., 2005). Such effects include weight gain, hyperphagia, enhanced visceral adiposity and elevated Levels of insulin and adiponectin. As sex differences have been reported in the effects of antipsychotic drugs, including OLZ, in rats, the current study extended our study in female rats by directly comparing the actions of OLZ in maLes using identical methodology. Individually housed male Han Wistar rats were administered OLZ twice daily (i.p.), at 0, 1, 2, and 4 mg/kg over 21 days. Both differences from, and simiLarities to, the data obtained in females were obtained. Males treated with OLZ showed reduced weight gain, enhanced visceral adiposity and reduced lean muscle mass. There were no accompanying changes in food or water intake. OLZ did not induce changes in plasma levels of insulin, leptin or glucose. Significant elevation of adiponectin was observed. OLZ-treated males displayed elevated prolactin and suppressed testosterone. OLZ's effects in humans can very clearly be most validly modelled in female rats, although the cause(s) of the sex difference in OLZ's actions in rats are not clear. However, the finding that significantly enhanced adiposity is seen in both male and female rats, in other animal species (mice and dogs) and in humans suggests that studies in male rats of OLZ's effects may be of value, by highlighting the consistent ability of OLZ to increase visceral adiposity. It is hypothesized that such adiposity is a key, clinically relevant, common component of OLZ's actions which may be, at Least partially, independent of both OLZinduced weight gain and hyperphagia, and which is induced reliably in male and female rats and other animal species. Possible mechanisms involved in the effects reported are discussed.

Metformin prolongs the postprandial fall in plasma ghrelin concentrations in type 2 diabetes

BACKGROUND

Weight loss is difficult to achieve in type 2 diabetes and many therapies are associated with weight gain, an effect attenuated by metformin. We studied the effects of metformin on energy expenditure, appetite and the regulation of PYY and ghrelin in type 2 diabetes.

METHODS

Plasma peptide YY (PYY), ghrelin, resting metabolic rate (RMR), postprandial thermogenesis (PPTG), and appetite ratings were measured at baseline and following a mixed meal in 11 type 2 diabetic subjects treated with diet alone (T2D) and 10 treated with metformin monotherapy (T2MF). The groups were similar in age, gender and adiposity.

RESULTS

There were no differences in baseline anthropometric, or metabolic variables between the groups. Postprandially, plasma ghrelin fell equally in both groups (23% versus 24.5%, p < 0.05 versus baseline, p = NS between groups) but were reduced for longer in T2MF (below baseline 60-240 min T2MF versus 60-180 min T2D) coincidentally with a prolonged sensation of fullness and suppression of hunger in the metformin-treated group. There were no differences in PYY concentrations, RMR or PPTG.

CONCLUSIONS

Metformin prolongs the postprandial fall in ghrelin concentrations. These effects may prolong the inter-meal interval, thereby decreasing snack intake and daily energy intake, promoting weight loss.

Cardiovascular disease, hypertension, dyslipidaemia and obesity in patients with hypothalamic-pituitary disease

OBJECTIVE

Adults with hypothalamic-pituitary disease have increased morbidity and mortality from cardiovascular disease (CVD). Therefore, the prevalence of CVD and adequacy of treatment of cardiovascular risk factors (according to current treatment guidelines) was studied in a large group of patients with hypothalamic-pituitary disease.

STUDY DESIGN

In 2005, 152 consecutive adult patients with hypothalamic-pituitary disease attending our neuro-endocrine centre were clinically examined and blood pressure (BP), lipid profile, type 2 diabetes mellitus, body composition and smoking status were assessed.

RESULTS

Of the 152 patients, 36.8% had treated hypertension and 28.2% had treated dyslipidaemia. Many of these patients had inadequate BP control (BP >140/85 mm Hg, 44.6%) and undesirable lipid levels (total cholesterol >4.0 mmol/l, 69%). Also, many of the untreated patients had BP and lipid levels which should have been considered for treatment (26 patients (27%) and 83 patients (76%), respectively). Smoking was admitted in 18% of patients. Central adiposity was present in 86% and obesity (body mass index > or =30) was present in 50%.

CONCLUSIONS

Cardiovascular risk factors are highly prevalent and often inadequately treated in adult patients with hypothalamic-pituitary disease. Aggressive treatment of these factors is essential to reduce mortality and morbidity from CVD in these patients.

Cardiovascular and metabolic effects of CPAP in obese males with OSA

Obstructive sleep apnoea is associated with increased blood pressure and other features of the metabolic syndrome. The aim of the present study was to determine the relative effectiveness of continuous positive airway pressure (CPAP) in modifying these outcomes. A randomised placebo-controlled blinded crossover trial comparing cardiovascular and metabolic outcomes after 6 weeks of therapeutic and sham CPAP was performed in 34 CPAP-naïve patients (mean+/-SD body mass and respiratory disturbance indices were 36.1+/-7.6 and 39.7+/-13.8, respectively). Mean waking systolic and diastolic blood pressure fell by 6.7 and 4.9 mmHg, respectively, when compared with sham CPAP. No change was observed in glucose, lipids, insulin resistance or the proportion of patients with metabolic syndrome. In CPAP-compliant patients the fall in blood pressure was greater and the baroreceptor sensitivity improved significantly but no metabolic variable changed. In obese Caucasians with untreated obstructive sleep apnoea, continuous positive airways pressure can improve baroreceptor responsiveness and reduce waking blood pressure within 6 weeks, but this treatment period was insufficient to modify insulin resistance or change the metabolic profile. The mechanisms underlying this difference in the time course of blood pressure and metabolic response to continuous positive airway pressure in obstructive sleep apnoea requires further exploration.

Effects of S 15511, a therapeutic metabolite of the insulin-sensitizing agent S 15261, in the Zucker Diabetic Fatty rat

AIM

S 15261 is a novel oral antihyperglycaemic drug with both insulin secretagogue and insulin-sensitizing effects. The study was designed to determine the biological activity of its two major metabolites, S 15511 and Y 415, and whether or not they have an additive effect.

METHODS

Zucker Diabetic Fatty rats were treated for 28 days with S 15511 (10 mg/kg), Y 415 (10 mg/kg), or a combination at the same doses for a period of 4 weeks starting at 6-7 weeks of age. An additional group was pair-fed to the level of S 15511-treated animals to determine if possible effects were due to reduced food intake.

RESULTS

S 15511 alone and combined with Y 415 reduced energy intake and weight gain (-13% vs. controls; both p < 0.01). Baseline fasting plasma glucose levels were maintained by S 15511, S 15511 + Y 415 and pair-feeding (p < 0.01) for the entire treatment period (p < 0.01). Baseline insulin was maintained by pair-feeding only, whereas all other treated groups became hyperinsulinaemic (+110-276%; p < 0.05). Deterioration in insulin sensitivity [homeostasis model assessment (HOMA)-IR: + 239%; p < 0.01] was attenuated by S 15511, S 15511 + Y 415 and pair-feeding (p < 0.01) and was compensated for by improved insulin secretion (HOMA-beta; p < 0.01). Oral glucose tolerance tests, performed on days 0, 14 and 28, showed that all groups had an impaired insulin response, but by day 28, S 15511, S 15511 + Y 415 and pair-feeding had improved glucose disposal compared to the progressive deterioration in untreated controls (-44% to -48% vs. controls; p < 0.01), associated with progression to frank diabetes in these animals.

CONCLUSION

Treatment with these agents in a genetic model of type 2 diabetes reveals that they all have a transient effect compared to the progressive worsening of vehicle-treated controls. The improvements in glucose metabolism observed with S 15511 are significant, however, suggesting it has more therapeutic activity than the Y 415 metabolite of S 15261. It is associated with less frequent progression to diabetes; i.e. Y 415 exerts a non-significant effect alone and no significant additive effect when combined with S 15511. The mechanism of action of S 15511 may be via increased insulin sensitivity and beta-cell response preservation up to day 21. Thus, previously reported insulin secretagogue effects are likely to be attributable to the parent compound.

Gut peptides and the regulation of appetite

There is a growing worldwide epidemic of obesity. Obese people have a higher incidence of type 2 diabetes and cardiovascular disease, and hence present increasing social, financial and health burdens. Weight loss is always difficult to achieve through lifestyle changes alone, and currently licensed anti-obesity drug treatments, such as orlistat and sibutramine, if tolerated, only achieve modest weight loss. Therefore, there is a need to identify more potent pharmacological targets. In the last 10 years, discoveries of new hormones such as leptin and ghrelin, together with greater understanding of previously described hormones such as cholecystokinin (CCK), pancreatic polypeptide (PP), peptide YY (PYY) and glucagon-like peptide 1 (GLP-1), have led to a rapid increase in our knowledge of the regulation of energy balance. Among the most important factors, controlling appetite and satiety are peptide hormones released from the gut. In this paper, we provide a full up-to-date overview of the current state of knowledge of this field, together with the potential of these peptides as drugs, or as other therapeutic targets, in the treatment of obesity. Finally, we propose an integrated model to describe the complex interplay of these hormones in the broader physiology of energy balance.

Prevalence of obesity in type 2 diabetes in secondary care: association with cardiovascular risk factors

AIMS

To determine the prevalence of overweight and obesity among patients with type 1 and type 2 diabetes mellitus attending a secondary care diabetes clinic in the United Kingdom, and to assess the impact of overweight and obesity on glycaemic control and cardiovascular risk factors in patients with type 2 diabetes.

METHODS

3637 patients with diabetes were identified from the hospital electronic diabetes register, 916 with type 1 diabetes (mean (SD) age 40.4 (15.1) years, 496 male) and 2721 with type 2 diabetes (mean (SD) age 62.5 (11.8) years, 1436 male). Data on body mass index (BMI), glycaemic control, lipid profiles, and blood pressure were extracted.

RESULTS

Of patients with type 1 diabetes, 55.3% were overweight (BMI >or=25 kg/m(2)), 16.6% were obese (BMI >or=30 kg/m(2)), and 0.4% had morbid obesity (BMI >or=40 kg/m(2)). In contrast, 86% of patients with type 2 diabetes were overweight or obese, 52% were obese, and 8.1% had morbid obesity. Obese patients with type 2 diabetes were younger, had poorer glycaemic control, higher blood pressures, worse lipid profiles, and were more likely to be receiving antihypertensive and lipid lowering drugs compared with patients with BMI <30 kg/m(2).

CONCLUSIONS

Obesity is the rule among patients attending this hospital diabetes clinic, with 86% of those with type 2 diabetes overweight or obese. Obesity is associated with significantly worse cardiovascular risk factors in this patient group, suggesting that more active interventions to control weight gain would be appropriate.

Adipokines and the insulin resistance syndrome in familial partial lipodystrophy caused by a mutation in lamin A/C

AIMS/HYPOTHESIS

Familial partial lipodystrophy (FPLD) and obesity are both associated with increased risks of type 2 diabetes and cardiovascular disease. Although adipokines have been implicated, few data exist in subjects with FPLD; therefore we investigated a family with FPLD due to a lamin A/C mutation in order to determine how abnormalities of the plasma adipokine profile relate to insulin resistance and the metabolic syndrome.

METHODS

Plasma levels of adiponectin, leptin, resistin, IL-1beta, IL-6 and TNF-alpha in 30 subjects (ten patients, 20 controls) were correlated with indices of metabolic syndrome.

RESULTS

Compared with controls, FPLD patients had significantly lower plasma levels of adiponectin (3.7+/-1.0 in FDLP cases vs 7.1+/-0.72 mug/ml in controls, p=0.02), leptin (1.23+/-0.4 vs 9.0+/-1.3 ng/ml, p=0.002) and IL-6 (0.59+/-0.12 vs 1.04+/-0.17 pg/ml, p=0.047) and elevated TNF-alpha (34.8+/-8.1 vs 13.7+/-2.7 pg/ml, p=0.028), whereas IL-1beta and resistin were unchanged. In both groups, adiponectin levels were inversely correlated with body fat mass (controls, r=-0.44, p=0.036; FDLP, r=-0.67, p=0.025), insulin resistance (controls, r=-0.62, p=0.003; FDLP, r=-0.70, p=0.025) and other features of the metabolic syndrome. TNF-alpha concentrations were positively related to fat mass (controls, r=0.68, p=0.001; FDLP, r=0.64, p=0.048) and insulin resistance (controls, r=0.86, p=0.001; FDLP, r=0.75, p=0.013). IL-6, IL-1beta and resistin did not demonstrate any correlations with the metabolic syndrome in either group.

CONCLUSIONS/INTERPRETATION

Low adiponectin and leptin and high TNF-alpha were identified as the major plasma adipokine abnormalities in FPLD, consistent with the hypothesis that low adiponectin and high TNF-alpha production may be mechanistically related, and perhaps responsible for the development of insulin resistance and cardiovascular disease in FPLD.

A parametric analysis of olanzapine-induced weight gain in female rats

RATIONALE

Some novel antipsychotics, including olanzapine, induce weight gain and metabolic abnormalities, which represent the major adverse effects of these drugs. However, the mechanism(s) involved in such effects are unclear.

OBJECTIVE

The aim of this study was to develop, in female rats, a parametric model of olanzapine-induced weight gain and metabolic abnormalities and evaluate it against clinical findings.

METHODS

Female rats were administered olanzapine b.i.d. at doses of 0, 1, 2 and 4 mg/kg over 20 days, and a wide range of variables were recorded during and after drug administration.

RESULTS

Olanzapine increased both 24 h and total food intake. This was associated with rapid onset weight gain and increased adiposity (assessed by visceral fat pad masses). Insulin, but not glucose, concentrations were elevated, with a significant increase in the HOMA-IR index, indicative of insulin resistance. A nonsignificant trend towards higher levels of leptin was observed. Paradoxically, there was a significant increase in adiponectin. All of these variables showed maximal increases at either 1 or 2 mg/kg and attenuated effects at 4 mg/kg. Prolactin levels were also increased by olanzapine. However, for this variable, there was a clear dose-response curve, with the maximal effect at the highest dose (4 mg/kg).

CONCLUSIONS

These data suggest that aspects of olanzapine-induced weight gain and metabolic abnormalities can possibly be modelled in female rats. It is suggested that olanzapine-induced hyperphagia acts as an initial stimulus which leads to weight gain, enhanced visceral adiposity and subsequent insulin resistance, although the latter may be ameliorated by compensatory responses in adiponectin levels. Prolactin elevation appears likely not to be involved in the weight gain, adiposity and metabolic changes seen in this model.

Insulin resistance and inflammatory activation in older patients with systolic and diastolic heart failure

OBJECTIVE

To evaluate insulin resistance and systemic inflammation in older patients with systolic (SHF) or diastolic heart failure (DHF).

PATIENTS

52 non-diabetic patients (> 70 and < 90 years old) with chronic heart failure (CHF) and hospitalised within the previous six months for heart failure were studied, together with a control group of older healthy volunteers (n = 26). On the basis of Doppler echocardiographic criteria patients were classed as having SHF (n = 27) or DHF (n = 25).

MAIN OUTCOME MEASURES

Fasting glucose, insulin, C reactive protein, interleukin 6, and tumour necrosis factor alpha soluble receptor II (TNF-alphaSRII) concentrations were determined. Insulin resistance was estimated by the homeostasis model assessment (HOMA).

RESULTS

HOMA index (median, interquartile range) was higher in patients with DHF (1.77, 1.06-2.26) than in patients with SHF (0.97, 0.81-1.85) or healthy volunteers (1.04, 0.76-1.44; p = 0.01). After adjustment for body mass index, age, and use of angiotensin converting enzyme inhibitors, both groups of patients with CHF were more insulin resistant than were healthy volunteers (p = 0.02). C reactive protein, interleukin 6, and TNF-alphaSRII were all significantly (p < 0.001) higher in patients with DHF and SHF than in healthy volunteers. All markers of systemic inflammation were independently associated with the presence of clinical CHF.

CONCLUSION

Insulin resistance and inflammatory activation are present in older patients with SHF and DHF.

Reduced ventromedial hypothalamic neuronal nitric oxide synthase and increased sensitivity to NOS inhibition in dietary obese rats: further evidence of a role for nitric oxide in the regulation of energy balance

Inhibition of hypothalamic nitric oxide (NO) decreases energy intake, and changes in hypothalamic NO synthase (NOS) have been observed in genetically obese rodents, but it is not known if NO is involved in the development of diet-induced obesity (DIO). We therefore measured changes in hypothalamic neuronal NOS (nNOS) in DIO and investigated effects of peripheral and central inhibition of NOS in this model. Expression of nNOS in relation to changes in nutritional state was measured by immunohistochemistry, with radiochemical detection. The effect of chronic intraperitoneal (i.p.) administration of the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 50 mg/kg/day) on energy intake, bodyweight and hypothalamic nitric oxide content was assessed in both chow-fed and DIO animals. Twenty-four hour energy intake after acute intracerebroventricular (i.c.v.) of L-NAME was also measured. Diet-induced obese animals had a statistically significant 32% reduction in the number of nNOS-immunolabelled cells in the ventromedial hypothalamus compared to chow-fed controls. Intraperitoneal administration of L-NAME decreased hypothalamic NO content in both chow-fed and DIO. Energy intake was reduced by 16% in DIO over 16 days, whereas energy intake was only reduced by 11% in chow-fed animals, although both were statistically significant. L-NAME significantly reduced body weight gain in DIO but not in chow-fed rats. L-NAME administered i.c.v. decreased 24 h energy intake to a greater extent in DIO rats, by 18%, compared with a 10% reduction in chow-fed rats. Ventromedial hypothalamic expression of nNOS is sensitive to changes in nutritional state. Despite having reduced nNOS, dietary obese rats were more sensitive to the effects of NOS inhibition than lean controls, suggesting a role for NO in the development of hyperphagia and obesity in rats fed a palatable diet.

Rosiglitazone improves insulin sensitivity, glucose tolerance and ambulatory blood pressure in subjects with impaired glucose tolerance

AIMS

To determine the effects of rosiglitazone on insulin sensitivity, glucose tolerance and ambulatory blood pressure when administered to subjects with persistent impaired glucose tolerance (IGT).

METHODS

Eighteen subjects with persistent IGT were randomized to receive rosiglitazone 4 mg twice daily or matching placebo for 12 weeks. Evaluation at baseline and at the end of treatment included measurement of whole body insulin sensitivity during a euglycaemic hyperinsulinaemic clamp and deriving an insulin sensitivity index. Changes in glucose and insulin concentration were determined after oral glucose tolerance test (OGTT) and mixed meal tolerance tests, and 24-h ambulatory blood pressure was monitored.

RESULTS

Rosiglitazone significantly improved the insulin sensitivity index by 2.26 micro g/kg per min per pmol/l relative to placebo (P = 0.0003). Four of nine subjects receiving rosiglitazone reverted to normal glucose tolerance and 5/9 remained IGT, although four of these had improved 2-h glucose values. In the placebo group, 1/9 subjects progressed to Type 2 diabetes and 8/9 remained IGT. Following OGTT and meal tolerance test, glucose and insulin area under curve were reduced over 3 and 4 h, respectively. Compared with placebo, ambulatory blood pressure decreased significantly in the rosiglitazone group by 10 mmHg systolic (P = 0.0066) and 8 mmHg diastolic (P = 0.0126).

CONCLUSIONS

Consistent with its effects in patients with Type 2 diabetes, rosiglitazone substantially improved whole body insulin sensitivity and the glycaemic and insulinaemic responses to an OGTT and meal tolerance test in subjects with persistent IGT. Furthermore, rosiglitazone reduced systolic and diastolic ambulatory blood pressure in these subjects.