Dunnigan lipodystrophy syndrome: French National Diagnosis and Care Protocol (PNDS; Protocole National de Diagnostic et de Soins)

Dunnigan syndrome, or Familial Partial Lipodystrophy type 2 (FPLD2; ORPHA 2348), is a rare autosomal dominant disorder due to pathogenic variants of the LMNA gene. The objective of the French National Diagnosis and Care Protocol (PNDS; Protocole National de Diagnostic et de Soins), is to provide health professionals with a guide to optimal management and care of patients with FPLD2, based on a critical literature review and multidisciplinary expert consensus. The PNDS, written by members of the French National Reference Center for Rare Diseases of Insulin Secretion and Insulin Sensitivity (PRISIS), is available on the French Health Authority website (in French). Dunnigan syndrome is characterized by a partial atrophy of the subcutaneous adipose tissue and by an insulin resistance syndrome, associated with a risk of metabolic, cardiovascular and muscular complications. Its prevalence, assessed at 1/100.000 in Europe, is probably considerably underestimated. Thorough clinical examination is key to diagnosis. Biochemical testing frequently shows hyperinsulinemia, abnormal glucose tolerance and hypertriglyceridemia. Elevated hepatic transaminases (hepatic steatosis) and creatine phosphokinase, and hyperandrogenism in women, are common. Molecular analysis of the LMNA gene confirms diagnosis and allows for family investigations. Regular screening and multidisciplinary monitoring of the associated complications are necessary. Diabetes frequently develops from puberty onwards. Hypertriglyceridemia may lead to acute pancreatitis. Early atherosclerosis and cardiomyopathy should be monitored. In women, polycystic ovary syndrome is common. Overall, the management of patients with Dunnigan syndrome requires the collaboration of several health care providers. The attending physician, in conjunction with the national care network, will ensure that the patient receives optimal care through regular follow-up and screening. The various elements of this PNDS are described to provide such a support.

Whole-exome sequencing identifies the first French MODY 6 family with a new mutation in the NEUROD1 gene

AIM

The aim of the present study was to identify the affected gene in a French family with maturity-onset diabetes of the young (MODY) using whole-exome sequencing (WES).

METHODS

WES was performed in one patient with MODY, and candidate variants were confirmed in members of the immediate family by Sanger sequencing.

RESULTS

In the proband, a new heterozygous missense mutation (c.340A>C) was identified in the NEUROD1 gene by WES analysis and confirmed by Sanger sequencing. Additional Sanger sequencing of the proband's sister and mother revealed the same heterozygous mutation. The proband and his sister displayed typical clinical characteristics of MODY, while their mother had the same typical MODY features except for later onset. When clinical and biological profiles were established for all three patients, the severity of diabetes-related complications varied substantially from one family member to another.

CONCLUSION

A novel missense mutation found in NEUROD1 was associated with MODY 6 features in a single French family.

[Thyroiditis: What's new in 2019?]

Thyroiditis is a frequent and mostly benign disease that can sometimes disrupt the thyroid balance. Their diagnosis, as well as their aetiology, is a necessary step in the management of the patients. Painful thyroiditis includes acute thyroiditis of infectious origin and subacute thyroiditis. The first one can be treated by antibiotics or antifungals depending on the germ found. The second one will be treated with non-steroidal anti-inflammatory drugs or corticosteroids. In cases of Hashimoto's thyroiditis with overt hypothyroidism, replacement therapy with L-thyroxine will be adapted to the TSH level. As amiodarone treatment provides dysthyroidism, the thyroid status should be monitored regularly. Hypothyroidism will be treated using thyroid replacement therapy. Hyperthyroidism imposes a stop of amiodarone when it is possible. Treatment with synthetic antithyroid drugs (propyl-thio-uracil) or corticosteroids could be used whether there is an underlying thyroid disease or not. Immunotherapies with anti-PD-1/PDL1 or anti-CTLA-4 can also provide dysthyroidism. A monitoring of the thyroid assessment needs to be done in these patients, even if there are no clinical signs, which are not very specific in this context. The treatment of hypothyroidism will be based on thyroid replacement therapy according to the TSH level and the presence or absence of anti-TPO antibodies. Treatment of symptomatic hyperthyroidism may involve a prescription of beta-blockers, or synthetic antithyroid drugs in case of positive anti-TSH receptor antibodies. In all cases, it is desirable to contact an endocrinologist to confirm the diagnosis hypothesis and to decide on a suitable treatment.

Personality types in individuals with type 1 and type 2 diabetes

OBJECTIVE

The Type A personality, characterized by impatience, strong career ambition and competitiveness, is associated with greater sensitivity to external stress. Type 1 diabetes (T1D) is an auto-immune disease, which is potentially influenced by stress, unlike type 2 diabetes (T2D). The aim of this study was to assess whether individuals with T1D and T2D exhibited significant differences on the Type A personality scale. We also assessed the personality in patients with thyroid auto-immune diseases to validate potential links between auto-immune disease and Type A.

DESIGN AND METHODS

The Bortner questionnaire was used to assess Type A personality in 188 patients with T1D, 430 patients with T2D and 85 patients with auto-immune thyroid disease (Graves' disease or Hashimoto thyroiditis).

RESULTS

Type A Bortner scores were significantly higher in T1D patients than in T2D patients (188±34 vs 177±36, p<0.0001). Patients with auto-immune thyroid diseases and T1D patients had similar Type A Bortner scores (189±33 vs 188±34, p=0.860).

CONCLUSION

Patients with auto-immune T1D have higher Type A scores than T2D patients. Furthermore, patients with auto-immune thyroid disease also have elevated Type A scores similar to those observed in type 1 diabetes, suggesting that an elevated Type A score in T1D is potentially related to its autoimmune origin. This suggests a possible link between Type A personality and auto-immune diseases via stress-triggering psychobiological pathways. The different personality score between T1D and T2D is an important factor to consider that could influence the diabetes self-care coping strategies and long-term prognosis.

Glycaemic variability is associated with severity of coronary artery disease in patients with poorly controlled type 2 diabetes and acute myocardial infarction

BACKGROUND

In patients with type 2 diabetes (T2D), glycaemic variability (GV), another component of glycaemic abnormalities, is a novel potentially aggravating factor for coronary artery disease (CAD).

OBJECTIVES

The aim of our study was to identify interactions between GV and severity of CAD in diabetes patients admitted for acute myocardial infarction (AMI).

METHODS

All patients with T2D admitted to our university hospital for AMI from March 2015 to February 2017 who received intravenous (IV) insulin therapy and underwent coronary angiography were included. GV was assessed by mean amplitude of blood glucose excursion (MAGE) values taken within 2 days of admission. Patients with higher GV (highest MAGE tertile) were compared with those with lower GV (first and second MAGE tertiles).

RESULTS

A total of 204 patients were included: median age was 72 (61-81) years; 32% were female; HbA_1c was 7.3% (6.4-8.2%); diabetes duration was 10 (2-17.5) years; and MAGE value was 0.65 (0.43-0.92) g/L. Compared with those with lower GV, patients with the highest GV were more often women, treated with previous insulin, and had higher blood glucose and HbA_1c levels. In addition, patients with elevated GV had significantly higher SYNTAX scores: 17 (10-28) vs. 12 (6-22) (P = 0.009). Indeed, SYNTAX scores (OR: 1.05, 95% CI: 1.02-1.08; P = 0.001) remained independently associated with high GV beyond HbA_1c levels (OR: 1.51, 95% CI: 1.2-1.89; P <  0.001).

CONCLUSION

In AMI patients with poorly controlled diabetes, GV is associated with CAD severity beyond chronic hyperglycaemia. Although no causality can be determined from our observational study, the results suggest that, in AMI, early evaluation of GV might contribute to the identification of those diabetes patients at high risk, and serve as a therapeutic target for both primary and secondary prevention.

Malnutrition in type 2 diabetic patients does not affect healing of foot ulcers

AIM

Protein-energy malnutrition is known to be involved in wound healing. While wound healing in patients with diabetic foot ulcers (DFU) is a complex and multifactorial process, the role of malnutrition in this case has rarely been explored. The objective of this study was to determine whether the nutritional status of diabetic patients influences the healing of DFU.

METHODS

48 patients were included in this prospective, single-center study. All patients with comorbidities or factors involving malnutrition or influencing biological measurements were excluded. Patients were followed up for 24 weeks.

RESULTS

The malnutrition rate was 29.2% at baseline and 25.6% at the end of the study. The difference was not significant. Of the 35 patients with wound healing, 29% were undernourished at inclusion and 17% at the end of the study. Of the 12 patients without wound healing, 50% were undernourished at inclusion, and 42% at the end of the study. These differences were not significant. Rate and speed of wound healing were not associated with malnutrition at inclusion. 15% of patients without malnutrition at baseline had final malnutrition.

CONCLUSION

We demonstrated that wound healing was not affected by the initial presence of malnutrition. In our study, there is no evidence to support nutritional intervention to improve wound healing in diabetic patients. Nevertheless, malnutrition is responsible for an increase in morbidity and mortality and it is essential to identify malnutrition systematically for all patients with DFU, initially and during follow-up to treat it quickly and efficiently.

Type A competitiveness traits correlate with downregulation of c-Fos expression in patients with type 1 diabetes

AIM

Type A personality has been associated with increased survival in people with type 1 diabetes (T1D). Systemic low-grade inflammation may play a critical role, as suggested in recent reports, although the links between the inflammatory circulating transcriptome and Type A remain unknown. This prompted our exploration of the potential associations between Type A personality and c-Fos gene expression, a candidate gene closely linked to inflammatory processes, in T1D.

METHODS

Type A personality was assessed by Bortner questionnaire in patients with T1D, and two subscales - 'speed' and 'competitiveness' - were used to measure these specific dimensions of Type A. Expression of the c-Fos gene was assessed by a quantitative real-time polymerase chain reaction technique.

RESULTS

This pilot study included 20 men with T1D. Multivariable analyses showed an independent inverse association between Type A competitiveness score and c-Fos expression, while a regression model adjusted for age, body mass index and HbA_1c levels revealed a significant inverse relationship between c-Fos transcripts and Type A competitiveness (P = 0.003).

CONCLUSION

This strong association between Type A competitiveness and reduced c-Fos expression is in line with recent data suggesting a psychobiological influence of the Type A profile in T1D via inflammatory pathways.

GLP-1 receptor agonists in NAFLD

Non-alcoholic fatty liver disease (NAFLD) is very common in patients with type 2 diabetes (T2D), with approximately two-thirds having a diagnosis of the disease. Currently, the only validated treatment for NAFLD is weight loss. A number of studies of animal models and human trials have evaluated the effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on liver fat content and suggest that the treatment could represent a new alternative for NAFLD management. In this review, our focus is on the main studies regarding the effects of GLP-1RAs on NAFLD. Also, the mechanisms that might explain their beneficial effects on liver diseases are analyzed.

European Association for the Study of the Liver (EASL), European Association for the Study of Diabetes (EASD) and European Association for the Study of Obesity (EASO) clinical practice recommendations for the management of non-alcoholic fatty liver disease: evaluation of their application in people with Type 2 diabetes

AIMS

To evaluate the application of the recently proposed recommendations by the European Association for the Study of the Liver, European Association for the Study of Diabetes and European Association for the Study of Obesity for the diagnosis, treatment and follow-up of non-alcoholic fatty liver disease in people with Type 2 diabetes.

METHODS

A total of 179 people with Type 2 diabetes were included in this study. Liver fat content (assessed using proton magnetic resonance spectroscopy), fatty liver index score, non-alcoholic fatty liver disease fibrosis score, and SteatoTest and FibroTest scores were determined.

RESULTS

According to proton magnetic resonance spectroscopy, 68.7% of participants had steatosis (liver fat content >5.5%). The application of the guidelines using several combinations (fatty liver index + non-alcoholic fatty liver disease fibrosis scores, Steatotest + FibroTest scores, proton magnetic resonance spectroscopy + non-alcoholic fatty liver disease fibrosis score, proton magnetic resonance spectroscopy + FibroTest) resulted in a referral to a liver clinic for 33.5-84.9% people with Type 2 diabetes.

CONCLUSIONS

The application of these new algorithms for the diagnosis, and follow-up of non-alcoholic fatty liver disease would lead to an excessive number of people with Type 2 diabetes being referred to a liver clinic. We suggest that new clinical and/or biological biomarkers of steatosis and fibrosis be specifically validated in people with Type 2 diabetes.

Effects of anti-somatostatin agents on glucose metabolism

The anti-somatostatin agents used to treat acromegaly, Cushing's disease and neuroendocrine tumours also have hyperglycaemic effects. This is particularly true for pasireotide. Hyperglycaemic events are seen in 57-73% of patients with Cushing's treated with pasireotide, with a need to initiate antidiabetic treatment in about 50% of these patients. In acromegaly, treatment with pasireotide induces hyperglycaemia in 29-61% of patients. Pasireotide-induced hyperglycemia occurs early, within the first 3 months of treatment, due to a decrease in insulin secretion secondary to a fall in secretion of GLP-1 and GIP, and potentially also due to a direct inhibitory effect of pasireotide on beta cells. Close monitoring of blood glucose is mandatory in all patients during the first 3 months of treatment with pasireotide. Where necessary, antidiabetic treatment should be initiated, preferably with a DPP-4 inhibitor or a GLP-1 receptor agonist, both of which have proven efficacy in the control of hyperglycaemia induced by pasireotide.

Plasma apolipoprotein C1 concentration is associated with plasma triglyceride concentration, but not visceral fat, in patients with type 2 diabetes

INTRODUCTION

Apolipoprotein C1 (apoC1) is likely to play an important role in triglyceride (TG) metabolism. Mice overexpressing human apoC1 present decreased adipose tissue stores. This study aimed to determine whether apoC1 concentration influences fat mass and distribution and liver fat content (LFC) in patients with type 2 diabetes (T2D).

METHODS

ApoC1 concentrations were measured by ELISA in 113 T2D patients and 56 normolipidaemic-normoglycaemic subjects. Visceral and subcutaneous fat areas were determined by single-slice axial T1-weighted magnetic resonance imaging (MRI), while LFC was measured by hydrogen-1 ((1)H) MR spectroscopy.

RESULTS

ApoC1 concentrations were higher in T2D patients than in normolipidaemic-normoglycaemic subjects (P<0.0001), and did not correlate with visceral or subcutaneous fat areas, but significantly correlated with TG (P<0.0001) and LFC (P=0.02) in T2D patients. However, the correlation between apoC1 and LFC was lost after adjusting for TG. ApoC1 concentration was also significantly higher in T2D patients with TG<1.5mmol/L than in control subjects (P<0.0001), although both groups had similar TG levels. On multivariate analysis performed in T2D patients with TG<1.5mmol/L and control subjects, apoC1 concentration was independently and positively associated with type 2 diabetes (P<0.0001) and TG levels (P=0.03).

CONCLUSION

This study reports, for the first time, that apoC1 is increased in T2D patients and is significantly correlated with TG, whereas no association was found between apoC1 and adipose tissue. This indicates that, in T2D, apoC1 may play a role in TG metabolism, but is unlikely to modulate fat mass and distribution. This increased apoC1 concentration in T2D patients is not only explained by the increased TG level in T2D patients.

Unraveling the intrafamilial correlations and heritability of tumor types in MEN1: a Groupe d'étude des Tumeurs Endocrines study

BACKGROUND

MEN1, which is secondary to the mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Most studies demonstrated the absence of direct genotype-phenotype correlations. The existence of a higher risk of death in the Groupe d'étude des Tumeurs Endocrines-cohort associated with a mutation in the JunD interacting domain suggests heterogeneity across families in disease expressivity. This study aims to assess the existence of modifying genetic factors by estimating the intrafamilial correlations and heritability of the six main tumor types in MEN1.

METHODS

The study included 797 patients from 265 kindred and studied seven phenotypic criteria: parathyroid and pancreatic neuroendocrine tumors (NETs) and pituitary, adrenal, bronchial, and thymic (thNET) tumors and the presence of metastasis. Intrafamilial correlations and heritability estimates were calculated from family tree data using specific validated statistical analysis software.

RESULTS

Intrafamilial correlations were significant and decreased along parental degrees distance for pituitary, adrenal and thNETs. The heritability of these three tumor types was consistently strong and significant with 64% (s.e.m.=0.13; P<0.001) for pituitary tumor, 65% (s.e.m.=0.21; P<0.001) for adrenal tumors, and 97% (s.e.m.=0.41; P=0.006) for thNETs.

CONCLUSION

The present study shows the existence of modifying genetic factors for thymus, adrenal, and pituitary MEN1 tumor types. The identification of at-risk subgroups of individuals within cohorts is the first step toward personalization of care. Next generation sequencing on this subset of tumors will help identify the molecular basis of MEN1 variable genetic expressivity.

Adverse effects and safety of SGLT-2 inhibitors

In type 2 diabetes (T2DM), glycaemic control delays the development and slows the progression of complications. Although there are numerous glucose-lowering agents in clinical use, only approximately half of T2DM patients achieve glycaemic control, while undesirable side-effects, such as hypoglycaemia and body weight gain, often impede treatment in those taking these medications. Thus, there is a need for novel agents and treatment options. Sodium-glucose cotransporter-2 inhibitors (SGLT-2-i) have recently been developed for the treatment of T2DM. The available data suggest a good tolerability profile for the three available drugs - canagliflozin, dapagliflozin and empagliflozin - approved by the US Food and Drug Administration (FDA) for the American market as well as in other countries. The most frequently reported adverse events with SGLT-2-i are female genital mycotic infections, urinary tract infections and increased urination. The pharmacodynamic response to SGLT-2-i declines with increasing severity of renal impairment, requiring dosage adjustments or restrictions with moderate-to-severe renal dysfunction. Most patients treated with SGLT-2-i also have a modest reduction in blood pressure and modest effects on serum lipid profiles, some of which are beneficial (increased high-density lipoprotein cholesterol and decreased triglycerides) and others which are not (increased low-density lipoprotein cholesterol, LDL-C). A number of large-scale and longer-term cardiovascular trials are now ongoing. In patients treated with dapagliflozin, a non-significant excess number of breast and bladder cancers has been reported; considered as due to a bias, this is nevertheless being followed in the ongoing trials. No other significant safety issues have been reported so far. Although there is some benefit for several cardiovascular risk factors such as HbA1c, high blood pressure, obesity and increases in LDL-C, adequately powered trials are still required to determine the effects of SGLT-2-i on macrovascular outcomes.

MEN1 disease occurring before 21 years old: a 160-patient cohort study from the Groupe d'étude des Tumeurs Endocrines

CONTEXT

Multiple endocrine neoplasia Type-1 (MEN1) in young patients is only described by case reports.

OBJECTIVE

To improve the knowledge of MEN1 natural history before 21 years old.

METHODS

Obtain a description of the first symptoms occurring before 21 years old (clinical symptoms, biological or imaging abnormalities), surgical outcomes related to MEN1 Neuro Endocrine Tumors (NETs) occurring in a group of 160 patients extracted from the "Groupe d'étude des Tumeurs Endocrines" MEN1 cohort.

RESULTS

The first symptoms were related to hyperparathyroidism in 122 cases (75%), pituitary adenoma in 55 cases (34%), nonsecreting pancreatic tumor (NSPT) in 14 cases (9%), insulinoma in 20 cases (12%), gastrinoma in three cases (2%), malignant adrenal tumors in 2 cases (1%), and malignant thymic-NET in one case (1%). Hyperparathyrodism was the first lesion in 90 cases (56%). The first symptoms occurred before 10 years old in 22 cases (14%) and before 5 years old in five cases (3%). Surgery was performed before age 21 in 66 patients (41%) with a total of 74 operations: pituitary adenoma (n = 9, 16%), hyperparathyroidism (n = 38, 31%), gastrinoma (n = 1, 33%), NSPT (n = 5, 36%), and all cases of insulinoma, adrenal tumors, and thymic-NET. One patient died before age 21 due to a thymic-NET. Overall, lesions were malignant in four cases.

CONCLUSIONS

Various MEN1 lesions occurred frequently before 21 years old, but mainly after 10 years of age. Rare, aggressive tumors may develop at any age. Hyperparathyroidism was the most frequently encountered lesion but was not always the first biological or clinical abnormality to appear during the course of MEN1.

Deleterious effect of glycation on the ability of HDL to counteract the inhibitory effect of oxidized LDL on endothelium-dependent vasorelaxation

BACKGROUND

Contrary to high-density lipoprotein (HDL) from normolipidaemic and normoglycaemic subjects, HDL from diabetic patients loses its ability to reverse the inhibition of vasorelaxation induced by oxidized low-density lipoprotein (LDL). The aim of this study was to analyze the role of glycation, a major abnormality observed in diabetes, on the impairment of the vasorelaxant effect of HDL.

METHODS

HDL from healthy subjects was glycated in vitro by incubation in glucose 200 mmol/L for 3 days. Vasoreactivity was evaluated by the relaxation response to acetylcholine of rabbit aorta rings pre-contracted with noradrenaline, before and after 2 h incubation with or without different lipoprotein fractions (Krebs buffer, oxidized LDL, normal or glycated HDL alone and with oxidized LDL).

RESULT

The fructosamine/apolipoprotein AI ratio was significantly increased in glycated HDL compared with native HDL (53.63 ± 7.91 vs 18.51 ± 4.10 µmol/g; p < 0.05). Oxidized LDL inhibited endothelium-dependent vasodilation compared with Krebs buffer [maximal relaxation (Emax) = 53.15 ± 6.50 vs 98.67 ± 2.07%, p < 0.001]. Native HDL was able to counteract the oxidized LDL-induced inhibition of vasorelaxation (Emax = 76.93 ± 5.41 vs 53.15 ± 6.50%, p < 0.001). On the other hand, glycated HDL had no effect on oxidized LDL-induced inhibition of endothelium vasorelaxation compared with incubation with oxidized LDL alone (Emax = 52.98 ± 2.07 vs 53.15 ± 6.50%, not significant).

CONCLUSION

Glycation of HDL induces the loss of the ability of HDL to counteract the inhibitory effect of oxidized LDL on endothelium-dependent vasorelaxation, this is likely contributing to the impairment of antiatherogenic properties of HDL in diabetic patients.

Glucose lowering therapeutic strategies for type 2 diabetic patients with chronic kidney disease in primary care setting in france: a cross-sectional study

Aim. To understand glucose lowering therapeutic strategies of French general practitioners (GPs) in the management of type 2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD). Methods. A multicenter cross-sectional study was conducted from March to June 2011 among a sample of French GPs who contribute to the IMS Lifelink Disease Analyzer database. Eligible patients were those with T2DM and moderate-to-severe CKD who visited their GPs at least once during the study period. Data were collected through electronic medical records and an additional questionnaire. Results. 116 GPs included 297 patients: 86 with stage 3a (Group 1, GFR = 45-60 mL/min/1.73 m(2)) and 211 with stages 3b, 4, or 5 (Group 2, GFR < 45 mL/min/1.73 m(2)). Patients' mean age was approximately 75 years. Insulin was used in 19% of patients, and was predominant in those with severe CKD. More than two-thirds of patients were treated with glucose lowering agents which were either contraindicated or not recommended for CKD. Conclusion Physicians most commonly considered the severity of diabetes and not CKD in their therapeutic decision making, exposing patients to potential iatrogenic risks. The recent patient oriented approach and individualization of glycemic objectives according to patient profile rather than standard HbA1c would improve this situation.

[Pheochromocytoma: rare lethal challenging diagnosis that may be encountered by gynecologists and obstetricians]

Pheochromocytomas are rare but potentially lethal tumors responsible for malignant hypertension. They may be encountered by gynecologists and obstetricians. The diagnosis is difficult because it can be mistaken for diseases more frequent like preeclampsia or other pelvic tumors. We report two cases highlighting clinical clues such as labile hypertension, headache, sweating, palpitations and failure to respond to conventional treatment should prompt physicians to screen patients for pheochromocytoma by measuring the 24-hour urinary catecholamines. The surgery must be performed after using an appropriate preoperative treatment, in order not to trigger lethal outcome. During pregnancy, C-section is recommended.

Beyond glucose lowering: glucagon-like peptide-1 receptor agonists, body weight and the cardiovascular system

AIM

Glucagon-like peptide-1 (GLP-1) belongs to the incretin hormone family: in the presence of elevated blood glucose, it stimulates insulin secretion and inhibits glucagon production. In addition, GLP-1 slows gastric emptying. GLP-1 secretion has also been reported to potentially affect patients with type 2 diabetes (T2DM) compared with non-diabetics and, as enzymatic inactivation by dipeptidyl peptidase-4 (DPP-4) shortens the GLP-1 half-life to a few minutes, GLP-1 receptor agonists such as exenatide twice daily (BID) and liraglutide have been developed, and have become part of the management of patients with T2DM. This review focuses on the potential beneficial effects of these compounds beyond those associated with improvements in blood glucose control and weight loss, including changes in the cardiovascular and central nervous systems.

METHODS

This was a state-of-the-art review of the literature to evaluate the relationships between GLP-1, GLP-1 receptor agonists, weight and the cardiovascular system.

RESULTS

GLP-1 receptor agonists improve glucose control and do not significantly increase the risk of hypoglycaemia. Also, this new class of antidiabetic drugs was shown to favour weight loss. Mechanisms may involve central action, direct action by reduction of food intake and probably indirect action through slowing of gastric emptying. The relative importance of each activity remains unclear. Weight loss may improve cardiovascular outcomes in patients with T2DM, although GLP-1 receptor agonists may have other direct and indirect effects on the cardiovascular system. Reductions in myocardial infarct size and improvements in cardiac function have been seen in animal models. Beneficial changes in cardiac function were also demonstrated in patients with myocardial infarcts or heart failure. Indirect effects could involve a reduction in blood pressure and potential effects on oxidation. However, the mechanisms involved in the pleiotropic effects of GLP-1 receptor agonists have yet to be completely elucidated and require further study.

CONCLUSION

These compounds may play an important role in the treatment of patients with T2DM as their potential effects go beyond glucose-lowering (weight loss, potential improvement of cardiovascular risk factors). However, to better understand their place in the management of T2DM, further experimental and clinical prospective studies are required.

Cardiovascular complications in type 1 diabetes mellitus

Although the issue of cardiovascular complications in type 2 diabetic patients is widely discussed, and recommendations for such screening are available, it is less common to do so for type-1 diabetes. Yet, independent of age, the mortality rate due to ischaemic cardiac disease is higher among type 1 diabetic patients (both male and female) than in the general population. Type 1 diabetic patients have certain specific characteristics related not only to atherosclerotic plaque and cardiovascular risk factors, but also to their capacity for physical activity and to the prevention of cardiovascular complications induced by hypoglycaemia.

Lipid disorders in type 1 diabetes

Patients with type 1 diabetes (T1D) also present with lipid disorders. Quantitative abnormalities of lipoproteins are observed in T1D patients with poor glycaemic control (increased plasma triglycerides and low-density lipoprotein [LDL] cholesterol) or nephropathy (increased triglycerides and LDL cholesterol, low level of high density lipoprotein [HDL] cholesterol). In cases of T1D with optimal glycaemic control, plasma triglycerides and LDL cholesterol are normal or slightly decreased, while HDL cholesterol is normal or slightly increased. Several qualitative abnormalities of lipoproteins, which are potentially atherogenic, are observed in patients with T1D, even in those with good metabolic control. These abnormalities include increased cholesterol-to-triglyceride ratios within very low-density lipoprotein (VLDLs), increased triglycerides in LDLs and HDLs, compositional changes in the peripheral layer of lipoproteins, glycation of apolipoproteins, increased oxidation of LDLs and an increase in small, dense LDL particles. These qualitative changes in lipoproteins are likely to impair their function. In vitro, VLDLs and LDLs from patients with T1D induced abnormal responses in the cellular cholesterol metabolism of human macrophages. HDLs from patients with T1D are thought to be less effective in promoting cholesterol efflux from cells, and have been shown to have reduced antioxidative and vasorelaxant properties. These qualitative abnormalities are not fully explained by hyperglycaemia and may be partly due to peripheral hyperinsulinaemia associated with subcutaneous insulin administration. However, the precise consequences of these qualitative lipid changes on the development of cardiovascular disease in T1D are, as yet, unknown.

Effects of 20 mg rosuvastatin on VLDL1-, VLDL2-, IDL- and LDL-ApoB kinetics in type 2 diabetes

AIMS/HYPOTHESIS

In addition to its efficacy in reducing LDL-cholesterol, rosuvastatin has been shown to significantly decrease plasma triacylglycerol. The use of rosuvastatin may be beneficial in patients with type 2 diabetes, who usually have increased triacylglycerol levels. However, its effects on the metabolism of triacylglycerol-rich lipoproteins in type 2 diabetic patients remains unknown.

METHODS

We performed a randomised double-blind crossover trial of 6-week treatment with placebo or rosuvastatin 20 mg in eight patients with type 2 diabetes who were being treated with oral glucose-lowering agents. In each patient, an in vivo kinetic study of apolipoprotein B (ApoB)-containing lipoproteins with [13C]leucine was performed at the end of each treatment period. A central randomisation centre used computer-generated tables to allocate treatments. Participants, caregivers and those assessing the outcomes were blinded to group assignment.

RESULTS

Rosuvastatin 20 mg significantly reduced plasma LDL-cholesterol, triacylglycerol and total ApoB. It also significantly reduced ApoB pool sizes of larger triacylglycerol-rich VLDL particles (VLDL1; p = 0.011), smaller VLDL particles (VLDL2; p = 0.011), intermediate density lipoprotein (IDL; p = 0.011) and LDL (p = 0.011). This reduction was associated with a significant increase in the total fractional catabolic rate of VLDL1-ApoB (6.70 +/- 3.24 vs 4.52 +/- 2.34 pool/day, p = 0.049), VLDL2-ApoB (8.72 +/- 3.37 vs 5.36 +/- 2.64, p = 0.011), IDL-ApoB (7.06 +/- 1.68 vs 4.21 +/- 1.51, p = 0.011) and LDL-ApoB (1.02 +/- 0.27 vs 0.59 +/- 0.13, p = 0.011). Rosuvastatin did not change the production rates of VLDL2-, IDL- or LDL-, but did reduce VLDL1-ApoB production rate (12.4 +/- 4.5 vs 19.5 +/- 8.4 mg kg(-1) day(-1), p = 0.035). No side effects of rosuvastatin were observed during the study.

CONCLUSIONS/INTERPRETATION

In type 2 diabetic patients rosuvastatin 20 mg not only induces a significant increase of LDL-ApoB catabolism (73%), but also has favourable effects on the catabolism of triacylglycerol-rich lipoproteins, e.g. a significant increase in the catabolism of VLDL1-ApoB (48%), VLDL2-ApoB (63%) and IDL-ApoB (68%), and a reduction in the production rate of VLDL1-ApoB (-36%). The effects of rosuvastatin on the metabolism of triacylglycerol-rich lipoproteins may be beneficial for prevention of atherosclerosis in type 2 diabetic patients.

Distinct patterns of heparin affinity chromatography VLDL1 and VLDL2 subfractions in the different dyslipidaemias

Very low density lipoprotein (VLDL) 1 and 2 were fractionated by heparin affinity chromatography into a bound and an unbound fraction and the different subfractions were quantified in 17 normolipidaemic (NL), 13 hypercholesterolaemic (HC), 10 hypertriglyceridaemic (HTG) and 11 combined hyperlipidaemic subjects (CHL). Unbound VLDL1 and VLDL2 were, respectively, 1.9- and 2.2-fold richer in triglycerides than bound VLDL1 and VLDL2. In HTG and CHL the concentration of all the VLDL subfractions was increased and plasma triglyceride level was correlated to unbound VLDL1 and to bound VLDL1 (respectively, r=0.86 (p<0.001) and r=0.77 (p<0.01) in HTG and r=0.73 (p<0.001) and r=0.62 (p<0.05) in CHL). In HC unbound VLDL2 and bound VLDL2 concentration were increased compared to NL and in CHL, the concentration of bound VLDL2 was particularly increased (3.2-fold compared to NL (p<0.001)). In both HC and CHL bound VLDL2 concentration was correlated to low density lipoprotein cholesterol (LDL-C) concentration (respectively, r=0.67 (p<0.01) and r=0.62 (p<0.05)). In hypertriglyceridaemic states the intravascular accumulation of both unbound and bound VLDL1 appears as the determinant of plasma triglyceride concentration, whereas in moderately hypercholesterolaemic states the concentration of bound VLDL2 is strikingly correlated to LDL-C concentration, suggesting that these two species are linked metabolically, e.g. bound VLDL2 contain the precursor pool of LDL.

HDL particles from type 1 diabetic patients are unable to reverse the inhibitory effect of oxidised LDL on endothelium-dependent vasorelaxation

AIMS/HYPOTHESIS

In healthy individuals, HDL can counteract the inhibition of vasorelaxation induced by oxidised LDL. Several abnormalities such as increased size, glycation and decreased paraoxonase activity have been reported for HDL from type 1 diabetic patients. Thus, we hypothesised that the ability of HDL to protect vessels against impairments of vasorelaxation would be decreased in these patients.

METHODS

We compared the ability of HDL from 18 type 1 diabetic patients and 12 control participants to counteract the inhibition of endothelium-dependent relaxation induced by oxidised LDL on rabbit aorta rings.

RESULTS

Serum triacylglycerol and total cholesterol, LDL- and HDL-cholesterol were similar in type 1 diabetic and control participants. Fasting glycaemia and the HDL-fructosamine level were higher in diabetic patients than in controls (9.06 +/- 3.55 vs 5.27 +/- 0.23 mmol/l, p < 0.005; and 10.2 +/- 3.2 vs 7.7 +/- 2.5 micromol/g protein, p < 0.05, respectively). HDL composition, size and paraoxonase activity were similar in both groups. HDL from controls reduced the inhibitory effect of oxidised LDL on maximal relaxation (E (max); 79.3 +/- 11.8 vs 66.4 +/- 11.7%, p < 0.05), whereas HDL from type 1 diabetic patients had no effect (E (max) = 70.6 +/- 17.4 vs 63.9 +/- 17.2%, NS). In type 1 diabetic patients, E (max) was not correlated with glycaemia or the HDL-fructosamine level.

CONCLUSIONS/INTERPRETATION

HDL particles from type 1 diabetic patients do not protect against inhibition of endothelium-dependent vasorelaxation induced by oxidised LDL, in contrast to HDL particles from healthy individuals. This defect cannot be explained by abnormalities in HDL composition, size or paraoxonase activity, and may contribute to the early development of atherosclerotic lesions in type 1 diabetic patients.

[The best of cardiac rehabilitation in 2006]

The meta-analysis showing the benefits of physical training revisited: Taylor examined only the cardiac rehabilitation trials of exercise intervention alone (versus usual care) and demonstrated that cardiac mortality is 28 % reduced and exercise appears to have an independent mortality benefit. An economic evaluation of cardiac rehabilitation: a systematic review of 15 economic evaluations. Evidence to support the cost-effectiveness of supervised cardiac rehabilitation compared with usual care in myocardial infarction and heart failure was identified. But further well-designed trials are required. Pronostic value of some variables determined by exercise testing entering cardiac rehabilitation and after physical training. A beneficial effect of physical training versus usual care on BNP and neurohormones in patients with chronic heart disease. Patients on beta blockers after myocardial infarction: determination of a more accurate training heart frequency derived from the classical Karvonen's formula. The combination of trimetazidine with exercise training provides greater improvements in functional capacity, left ventricular function and the endothelium-dependent relaxation of the brachial artery than exercise training alone in patients with ischaemic cardiomyopathy referred for cardiac rehabilitation. Guidelines for resistance exercise after cardiac event: a new paradigm less restrictive, safe and efficient to accelerate patients' return to daily activities. Recommendations for participation in leisure-time physical activity and competitive sports for patients with ischaemic heart disease: the result of consensus among experts from the ESC study group of sports cardiology.