Methods of investigation for cardiac autonomic dysfunction in human research studies.

This consensus document provides evidence-based guidelines regarding the evaluation of diabetic cardiovascular autonomic neuropathy (CAN) for human research studies; the guidelines are the result of the work of the CAN Subcommittee of the Toronto Diabetic Neuropathy Expert Group. The subcommittee critically reviewed the limitations and strengths of the available diagnostic approaches for CAN and the need for developing new tests for autonomic function. It was concluded that the most sensitive and specific approaches currently available to evaluate CAN in clinical research are: (1) heart rate variability, (2) baroreflex sensitivity, (3) muscle sympathetic nerve activity, (4) plasma catecholamines, and (5) heart sympathetic imaging. It was also recommended that efforts should be undertaken to develop new non-invasive and safe CAN tests to be used in clinical research, with higher sensitivity and specificity, for studying the pathophysiology of CAN and evaluating new therapeutic approaches.

Cardiovascular autonomic neuropathy in diabetes: clinical impact, assessment, diagnosis, and management.

The Cardiovascular Autonomic Neuropathy (CAN) Subcommittee of the Toronto Consensus Panel on Diabetic Neuropathy worked to update CAN guidelines, with regard to epidemiology, clinical impact, diagnosis, usefulness of CAN testing, and management. CAN is the impairment of cardiovascular autonomic control in the setting of diabetes after exclusion of other causes. The prevalence of confirmed CAN is around 20%, and increases up to 65% with age and diabetes duration. Established risk factors for CAN are glycaemic control in type 1 and a combination of hypertension, dyslipidaemia, obesity, and glycaemic control in type 2 diabetes. CAN is a risk marker of mortality and cardiovascular morbidity, and possibly a progression promoter of diabetic nephropathy. Criteria for CAN diagnosis and staging are: (1) one abnormal cardiovagal test result identifies possible or early CAN; (2) at least two abnormal cardiovagal test results are required for definite or confirmed CAN; and (3) the presence of orthostatic hypotension in addition to abnormal heart rate test results identifies severe or advanced CAN. Progressive stages of CAN are associated with increasingly worse prognosis. CAN assessment is relevant in clinical practice for (1) diagnosis of CAN clinical forms, (2) detection and tailored treatment of CAN clinical correlates (e.g. tachycardia, orthostatic hypotension, non-dipping, QT interval prolongation), (3) risk stratification for diabetic complications and cardiovascular morbidity and mortality, and (4) modulation of targets of diabetes therapy. Evidence on the cost-effectiveness of CAN testing is lacking. Apart from the preventive role of intensive glycaemic control in type 1 diabetes, recommendations cannot be made for most therapeutic approaches to CAN.

Generalised arterial calcification in normoalbuminuric patients with type 1 diabetes with and without cardiovascular autonomic neuropathy.

BACKGROUND: Type 1 diabetes is associated with increased risk of cardiovascular disease and the diabetic complication cardiovascular autonomic neuropathy in itself entails increased cardiovascular risk by mechanisms not yet fully understood. Arterial calcification is an important predictor of cardiovascular events; the aim of this study was to investigate the level of generalised arterial calcification in patients with long-term, normoalbuminuric type 1 diabetes and the association with cardiovascular autonomic neuropathy, as these factors have not been investigated in type 1 diabetes. METHODS: Participants were examined for calcification of coronary and carotid arteries through non-contrast multi-detector computed tomography scans. Generalised arterial calcification was defined as the presence of calcium in both the coronary and carotid arteries. RESULTS: A total of 53 patients with type 1 diabetes were included. Coronary and carotid artery calcium scores were correlated ( r = 0.720, p < 0.0001). Cardiovascular autonomic neuropathy was associated with increased coronary ( p = 0.002) and carotid ( p = 0.001) artery calcium scores. Seventeen of 20 patients with cardiovascular autonomic neuropathy (85%) demonstrated generalised arterial calcification compared to 11 (33%) patients without cardiovascular autonomic neuropathy; patients with cardiovascular autonomic neuropathy had an odds ratio of 11.3 (95% confidence interval = 2.7-47.1, p < 0.001) for generalised arterial calcification. CONCLUSION: Cardiovascular autonomic neuropathy is associated with increased level of generalised arterial calcification in patients with normoalbuminuric, long-term type 1 diabetes.

Left ventricular remodelling and cardiac chamber sizes in long-term, normoalbuminuric type 1 diabetes patients with and without cardiovascular autonomic neuropathy.

AIMS: Type 1 diabetes is associated with increased cardiovascular (CV) morbidity and mortality, and cardiovascular autonomic neuropathy (CAN) is an important CV risk factor. The study aimed to explore associations between CAN and altered cardiac chamber sizes in persons with type 1 diabetes. METHODS: This was a cross-sectional study of 71 asymptomatic, normoalbuminuric participants with long-term type 1 diabetes (39 with CAN, determined by >1 abnormal autonomic function test) examined with cardiac multi detector computed tomography scans, which allowed measurements of left ventricular mass and all four cardiac chamber volumes. Cardiac chambers were indexed according to body surface area (ml/m2 or g/m2). RESULTS: Persons with and without CAN had mean ±â€¯SD age of 57 ±â€¯7 and 50 ±â€¯8 years (p < 0.001) and diabetes duration of 36 ±â€¯11 and 32 ±â€¯9 years (p < 0.05), respectively. Increasing autonomic dysfunction, evaluated by decrease in heart rate variability during deep breathing (in beats per minute), was associated with larger right (-0.5, 95% CI -1.0 to -0.0, p < 0.05) and trend towards larger left (-0.4, 95% CI -0.8-0.0, p < 0.1) ventricular volumes in multivariable linear regression. CONCLUSIONS: Our results suggest that impaired autonomic function may be associated with modest enlargement of ventricular volumes; this might be an early sign of progression towards heart failure.

Cardiac ventricular sizes are reduced in patients with long-term, normoalbuminuric type 1 diabetes compared to the non-diabetic background population.

AIMS: Type 1 diabetes entails increased cardiovascular morbidity and cardiac chamber sizes are associated with cardiovascular disease. The aim of this study was to compare cardiac chamber sizes in normoalbuminuric persons with type 1 diabetes to a background population without diabetes. METHODS: In a cross-sectional study, we examined 71 normoalbuminuric persons with long-term type 1 diabetes without known cardiovascular disease using cardiac multi-detector computed tomography. Cardiac chamber sizes and left ventricular remodelling were compared to persons without diabetes from the Copenhagen General Population Study. RESULTS: Participants were median (interquartile range) 54 (48-60) (type 1 diabetes) and 57 (50-64) (without diabetes) years old and 59% were men (both groups). Participants with type 1 diabetes had smaller left ventricular mass (-3.5 g/m2, 95% confidence interval -5.8 to -1.3) and left (-4.0 mL/m2, 95% confidence interval -6.9 to -1.0) and right (-11.7 mL/m2, 95% confidence interval -15.4 to -7.9) ventricular volumes in multivariable analyses (adjusted for age, sex, body composition, blood pressure and antihypertensive medication), but no differences in atrial volumes. CONCLUSION: Persons with long-term type 1 diabetes had smaller left ventricular mass and biventricular volumes, yet similar atrial sizes, compared to a background population without diabetes. These findings may reflect subclinical development of diabetic cardiomyopathy.

Targeting postprandial hyperglycaemia in patients with recently diagnosed type 2 diabetes with a fixed, weight-based dose of insulin Aspart.

OBJECTIVE: To assess the effect of substitution of early insulin release with a small weight-based dose of the rapid acting insulin analogue, insulin Aspart (IAsp), on postprandial hyperglycaemia in patients with recently diagnosed type 2 diabetes. MATERIAL AND METHODS: In a randomized, double-blind, double-dummy design, 20 patients underwent three 3-day periods with injection of IAsp 0.06 IU/kg BW or placebo 30 min before main meals. The effect on blood glucose fluctuations was evaluated using a continuous glucose monitoring system. Efficacy endpoints were time with glucose values above 8 mmol/L and glucose area above 8 mmol/L; safety endpoint was time with glucose values below 4 mmol/L in the last 24 h in the treatment periods. RESULTS: IAsp significantly reduced the duration of blood glucose values above 8 mmol/L compared with placebo during 24 h (8.1+/-1.4 h versus 12.7+/-1.3 h), (p<0.03). Glucose areas above 8 mmol/L were 0.6+/-0.2 mmol/lxh and 1.2+/-0.2 mmol/lxh for IAsp and placebo, respectively (p<0.001). Two patients (one in each of the IAsp and placebo periods) had two asymptomatic episodes of glucose registration below 4 mmol/L. Patients with HbA(1c) below 7.4 % obtained the greatest reduction in duration of blood glucose values above 8 mmol/L, whereas the decrease in blood glucose increments for patients with HbA(1c) above 7.4 % was not significantly different from placebo. CONCLUSIONS: A fixed dose of IAsp injected 30 min before mealtimes reduced the postprandial glucose increment in patients with recently diagnosed type 2 diabetes without the risk of hypoglycaemia. Glucose fluctuations in patients with HbA(1c) below 7.4 % improved to near normal level.

Possible early detection of coronary artery calcium progression in type 1 diabetes: A case-control study of normoalbuminuric type 1 diabetes patients and matched controls.

AIMS: Coronary artery calcium (CAC) is associated with cardiovascular (CV) disease and progression of CAC is an independent predictor of mortality. Type 1 diabetes is associated with increased CV risk, especially in persons with cardiovascular autonomic neuropathy (CAN). This study aimed to examine whether short-term progression of CAC is increased in persons with type 1 diabetes compared to matched controls and if CAN increases risk of CAC progression. METHODS: Fifty-three normoalbuminuric persons with long-term type 1 diabetes (20 with CAN) were matched in a 1:2 ratio with 106 controls without diabetes according to age, sex and baseline CAC. All were examined twice with cardiac computed tomography scans. Progression of CAC was defined as a value ≥2.5 between the square root-transformed values of follow-up and baseline CAC volume scores. RESULTS: The participants were examined median (interquartile range) of 25 (23-27) months (type 1 diabetes) and 29 (25-33) months (controls) apart. In multivariable logistic regression, participants with type 1 diabetes had an odds ratio of 3.3 (95% CI 1.3-8.2, p = 0.01) for CAC progression. CAN did not increase progression of CAC (p = 0.64). CONCLUSIONS: Progression of CAC was increased in well-treated, normoalbuminuric persons with type 1 diabetes compared to matched controls without diabetes, suggesting that type 1 diabetes is a risk factor for short-term progression. This finding could explain some of the increased morbidity and mortality observed in persons with type 1 diabetes, but it does not specifically explain the increased CV risk in persons with CAN.

Cardiac autonomic neuropathy predicts cardiovascular morbidity and mortality in type 1 diabetic patients with diabetic nephropathy.

OBJECTIVE: Cardiac autonomic neuropathy (CAN) has been associated with a poor prognosis in patients with diabetes. Because CAN is common in patients with diabetic nephropathy, we evaluated the predictive value of CAN in type 1 diabetic patients with and without diabetic nephropathy. RESEARCH DESIGN AND METHODS: In a prospective observational follow-up study, 197 type 1 diabetic patients with diabetic nephropathy and a matched group of 191 patients with long-standing type 1 diabetes and normoalbuminuria were followed for 10.1 years (range 0.0-10.3 years). At baseline, CAN was assessed by heart rate variation (HRV) during deep breathing. HRV was evaluated as a predictor of the primary end point: cardiovascular morbidity and mortality. As secondary end points, all-cause mortality and the influence of HRV on progression of diabetic nephropathy (decline in glomerular filtration rate [GFR]) was evaluated. RESULTS: During the follow-up, 79 patients (40%) with nephropathy reached the combined primary end point vs. 19 patients (10%) with normoalbuminuria (log-rank test, P < 0.0001). The unadjusted hazard ratio (HR) for reaching the primary end point when having an abnormal HRV (< or =10 bpm) measured at baseline compared with a normal HRV was 7.7 (range 1.9-31.5; P = 0.004) in patients with nephropathy. Similarly in the normoalbuminuric patients, the unadjusted HR was 4.4 (1.4-13.6; P = 0.009). In patients with nephropathy, abnormal HRV was significantly associated with fatal and nonfatal cardiovascular disease after adjustment for cardiovascular risk factors. The adjusted HR for reaching the primary end point in a patient with nephropathy and an abnormal HRV was 6.4 (1.5-26.3, P = 0.010), as compared with a normal HRV. The unadjusted HR for dying when having an abnormal HRV compared with a normal HRV was 3.3 (95% CI 1.0-10.7; P = 0.043) in patients with diabetic nephropathy. After adjustment for confounding factors, the impact of HRV on all-cause mortality in patients with nephropathy was no longer significant (P = 0.293). There was no relationship between abnormal HRV and rate of decline in GFR. CONCLUSIONS: HRV is an independent risk factor for cardiovascular morbidity and mortality in type 1 diabetic patients with nephropathy.

Effects of short-term caloric restriction on circulating free IGF-I, acid-labile subunit, IGF-binding proteins (IGFBPs)-1-4, and IGFBPs-1-3 protease activity in obese subjects.

OBJECTIVE: Decreased levels of GH and total IGF-I have been reported in obesity. It has been hypothesized that increased free (biologically active) IGF-I levels generated from IGF-binding protein (IGFBP) protease activity could be the mechanism for the low GH release in dieting obese subjects. However, no published data exist on free IGF-I levels, acid labile subunit (ALS), or IGFBP protease activity in relation to GH release during a hypocaloric diet. The main purpose of this study was to determine free IGF-I, ALS, IGFBPs-1-4, and IGFBPs-1-3 protease activity in relation to 24-h GH release before and after a short-term very low-calorie diet (VLCD). DESIGN: Six obese subjects before weight loss, five after an average weight loss of 36.1 kg, and five age-and sex-matched lean controls underwent a 4-day VLCD. All subjects were studied on two occasions, once during normal basic diet and again during the last day of the VLCD (1.6 MJ). METHODS: Free IGF-I was determined by a non-competitive immunoradiometric assay. RESULTS: Free IGF-I levels decreased in concert with increased ALS and unchanged blunted GH release after a VLCD in the obese subjects. IGFBPs-1-3 proteolytic activity was found to be unchanged by hypocaloric diet in all groups. CONCLUSIONS: We conclude that free IGF-I decreases after a short-term hypocaloric diet in obese subjects with no concomitant change in 24-h GH release. Circulating free IGF-I per se cannot be the main mechanism of the attenuated GH release in dieting obese subjects.

Nocturnal antihypertensive treatment in patients with type 1 diabetes with autonomic neuropathy and non-dipping: a randomised, placebo-controlled, double-blind cross-over trial.

OBJECTIVES: Cardiovascular autonomic neuropathy (CAN) and abnormal circadian blood pressure (BP) rhythm are independent cardiovascular risk factors in patients with diabetes and associations between CAN, non-dipping of nocturnal BP and coronary artery disease have been demonstrated. We aimed to test if bedtime dosing (BD) versus morning dosing (MD) of the ACE inhibitor enalapril would affect the 24-hour BP profile in patients with type 1 diabetes (T1D), CAN and non-dipping. SETTING: Secondary healthcare unit in Copenhagen, Denmark. PARTICIPANTS: 24 normoalbuminuric patients with T1D with CAN and non-dipping were included, consisting of mixed gender and Caucasian origin. Mean±SD age, glycosylated haemoglobin and diabetes duration were 60±7 years, 7.9±0.7% (62±7 mmol/mol) and 36±11 years. INTERVENTIONS: In this randomised, placebo-controlled, double-blind cross-over study, the patients were treated for 12 weeks with either MD (20 mg enalapril in the morning and placebo at bedtime) or BD (placebo in the morning and 20 mg enalapril at bedtime), followed by 12 weeks of switched treatment regimen. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was altered dipping of nocturnal BP. Secondary outcomes included a measurable effect on other cardiovascular risk factors than BP, including left ventricular function (LVF). RESULTS: Systolic BP dipping increased 2.4% (0.03-4.9%; p=0.048) with BD compared to MD of enalapril. There was no increase in mean arterial pressure dipping (2.2% (-0.1% to 4.5%; p=0.07)). No difference was found on measures of LVF (p≥0.15). No adverse events were registered during the study. CONCLUSIONS: We demonstrated that patients with T1D with CAN and non-dipping can be treated with an ACE inhibitor at night as BD as opposed to MD increased BP dipping, thereby diminishing the abnormal BP profile. The potentially beneficial effect on long-term cardiovascular risk remains to be determined. TRIAL REGISTRATION NUMBER: EudraCT2012-002136-90; Post-results.

Decreased myocardial perfusion reserve in diabetic autonomic neuropathy.

The pathophysiological mechanisms responsible for increased cardiovascular mortality in diabetic autonomic neuropathy are unknown. To investigate the effect of autonomic neuropathy on myocardial function, we performed dynamic contrast-enhanced magnetic resonance perfusion imaging during baseline conditions and after Dipyridamole-induced vasodilatation in nine type 1 diabetic patients with autonomic neuropathy (AN+), defined by cardiovascular tests, as well as in 10 type 1 diabetic patients without autonomic neuropathy (AN-) and 10 healthy control subjects. Baseline myocardial perfusion index (K(i)) was similar in the three groups (AN+ 88.6 +/- 8.7 ml. 100 g(-1). min(-1), AN- 82.6 +/- 7.2, control subjects 93.7 +/- 9.0) (means +/- SE). K(i) during Dipyridamole vasodilatation was significantly lower in the patients with autonomic neuropathy (P < 0.001) than in the other groups (AN+ 131.1 +/- 13.0 ml. 100 g(-1). min(-1), AN- 177.3 +/- 8.6, control subjects 197.2 +/- 8.9). Mean blood pressure was unchanged during Dipyridamole infusion in AN- and control subjects, whereas a significant blood pressure decrease was found in AN+ (15.6 +/- 2.6 mmHg, P < 0.025). There was a significant correlation between blood pressure response to Dipyridamole and myocardial perfusion reserve index. We conclude that type 1 diabetic patients with autonomic neuropathy have a decreased myocardial perfusion reserve capacity when challenged with a vasodilatator, a finding that may in part be the pathophysiological substrate for the increase in mortality in these patients. The underlying mechanism may be defective myocardial sympathetic vasodilatation, a lack of ability to maintain blood pressure during vasodilatation, or both.

Myocardial perfusion at rest in patients with Diabetes Mellitus Type 1 compared with healthy controls assessed with Multi Detector Computed Tomography.

AIM: Type 1 diabetes mellitus (T1DM) is associated with an increased risk of ischemic heart disease (IHD). The relative contribution of structural and functional abnormalities of the coronary circulation determining clinically manifested IHD remains unknown. The aim of this study was to assess potential differences in myocardial perfusion at rest and coronary atherosclerosis between asymptomatic T1DM patients and healthy controls. METHODS: Left ventricular (LV) myocardial perfusion at rest measured as LV myocardial Attenuation Density/LV blood pool Attenuation Density (MyoAD-ratio) and coronary artery atherosclerosis were evaluated with 320-multidetector computed tomography angiography in 57 asymptomatic T1DM patients and 114 sex and age matched controls. RESULTS: In both groups median age was 53 years (p5,p95: 42,67) and 59.6% were men. Median duration of diabetes in the T1DM group was 35 years (p5,p95: 17,49). Median coronary calcium score was higher in T1DM patients (51 vs. 2, p=0.037) compared with controls. However, a similar frequency of >50% stenosis in one or more coronary arteries was found in T1DM patients and controls (18% vs. 14%, p=0.49). LV myocardial perfusion at rest (MyoAD-ratio) was 18% higher in T1DM patients than controls (0.13 vs. 0.11, p<0.0001). This difference was noted throughout all the LV myocardial segments. In a multiple regression analysis including diabetes, sex, age, cardiovascular risk factors, heart rate, calcium score and coronary stenosis >50%, MyoAD-ratio remained significantly higher in T1DM patients (p=0.0001). CONCLUSIONS: LV myocardial perfusion at rest is higher in T1DM patients compared with controls independent of coronary atherosclerosis and cardiovascular risk factors.

Twenty-four-hour plasma tryptophan concentrations and ratios are below normal in obese subjects and are not normalized by substantial weight reduction.

BACKGROUND: Plasma tryptophan concentrations and the ratio of tryptophan to other large neutral amino acids (plasma tryptophan ratio) are reportedly low in obese subjects. The plasma tryptophan ratio predicts brain tryptophan uptake and serotonin production. If this ratio is low in obese subjects, serotonin function may also be low. Plasma tryptophan concentrations and ratios have been measured only at single time points in obese subjects; it is not known whether low values for these 2 variables persist throughout a 24-h period. OBJECTIVE: Our objective was to determine whether plasma tryptophan concentrations and ratios in obese subjects are lower than those in normal-weight subjects throughout a 24-h period and whether they increase when body weight is reduced. DESIGN: Plasma tryptophan concentrations and ratios were examined in obese subjects before and after weight loss and in nonobese control subjects. Blood samples were drawn frequently throughout the 24-h period. An insulin tolerance test was also used to determine whether weight loss altered the ability of insulin to modify plasma concentrations of tryptophan and of the other large neutral amino acids. RESULTS: Plasma tryptophan concentrations and ratios in obese subjects were low at all times; these effects persisted after weight reduction. Plasma concentrations of all the large neutral amino acids decreased during insulin infusion in all the groups. CONCLUSIONS: The low 24-h plasma tryptophan ratios in obese and formerly obese subjects suggest that brain tryptophan uptake may be continuously diminished and may remain below normal despite weight reduction.

Leisure-time activity is an important determinant of long-term weight maintenance after weight loss in the Sibutramine Trial on Obesity Reduction and Maintenance (STORM trial).

BACKGROUND: The success rate of long-term maintenance of weight loss in obese patients is usually low. To improve the success rate, determinants of long-term weight maintenance must be identified. OBJECTIVE: The objective of the study was to identify determinants of long-term success in weight maintenance in obese subjects who completed the Sibutramine Trial on Obesity Reduction and Maintenance (n = 261), a multicenter European study of weight loss and weight maintenance in obesity that combines sibutramine treatment with dietary restriction and advice on exercise and behavior. DESIGN: We studied weight maintenance over 18 mo in subjects who had completed a 6-mo weight-loss phase. Factors included in the analysis were initial body weight, the percentage of initial body weight lost, dietary intake, various components of physical activity (measured with the Baecke questionnaire), the type of treatment (sibutramine or placebo), age, and sex. RESULTS: Multiple regression analysis identified treatment group (sibutramine or placebo), the percentage of the initial body weight that was lost during the 6-mo weight-loss phase, and the leisure-time physical activity index as significant determinants of weight maintenance. Together, these 3 factors explained 20% of the variation in weight maintenance (P < 0.001). Dietary factors, age, and sex were not significant predictors of weight-maintenance success in this study. CONCLUSIONS: Weight-maintenance success after weight loss is positively influenced by sibutramine treatment during weight maintenance, by a greater initial weight loss, and by a higher leisure-time physical activity index, which reflects higher levels of activities such as walking and cycling and lower levels of television viewing.

Intravenous lidocaine infusion--a new treatment of chronic painful diabetic neuropathy?

In a randomized double-blind, cross-over study the effect of intravenous lidocaine (5 mg/kg body weight) on the symptoms and signs of painful diabetic neuropathy of more than 6 months duration has been evaluated. Using a clinical symptom scale, there was significant beneficial effect 1 and 8 days after lidocaine infusion compared to after saline infusion (P less than 0.05 and P less than 0.02, respectively). The duration of the individual effect ranged from 3 to 21 days. Lidocaine infusion had no effect on the objective measurements of neuropathy. Intravenous lidocaine infusion seems to be a new alternative treatment of chronic painful diabetic neuropathy.

[Administrative organization and responsibility]. / Administrativ organisation og ansvar.

The paper describes the current organisation of clinical trials in Danish hospitals, with particular emphasis on the relationship between hospitals and the pharmaceutical industry. Legal responsibilities as well as mutual agreements on collaboration and organisation are described and discussed.

Nocturnal antihypertensive treatment in patients with type 1 diabetes with autonomic neuropathy and non-dipping of blood pressure during night time: protocol for a randomised, placebo-controlled, double-blind, two-way crossover study.

INTRODUCTION: Cardiac autonomic neuropathy (CAN) and elevated nocturnal blood pressure are independent risk factors for cardiovascular disease in patients with diabetes. Previously, associations between CAN, non-dipping of nocturnal blood pressure and coronary artery calcification have been demonstrated. The present protocol describes a trial to test the efficacy of bedtime dosing of the ACE inhibitor enalapril on night time blood pressure and left ventricular mass in patients with type 1 diabetes. MATERIALS AND METHODS: In a randomised, double-blind, two-way cross-over study, 24 normoalbuminuric patients with type 1 diabetes with CAN will be treated for 12 weeks with either morning or bedtime dosing of 20 mg enalapril, followed by 12 weeks of switched treatment regimen. During each treatment period, two 24 h ambulatory blood pressure measurements will be performed and after each treatment period left ventricular mass will be determined by multisliced CT. Primary end points will be reduction in blood pressure and reduction in left ventricular mass. ETHICS AND DISSEMINATION: The study has been approved by the Danish Medicines Agency, the Scientific-Ethical Committee of the Capital Region of Denmark and the Danish Data Protection Agency. An external monitoring committee (the Good Clinical Practice Unit at Copenhagen University Hospital) will oversee the study. The results of the study will be presented at national and international scientific meetings and publications will be submitted to peer-reviewed journals. TRIAL REGISTRATION NUMBER: EudraCT (2012- 002136-90).

Cardiovascular autonomic neuropathy and subclinical cardiovascular disease in normoalbuminuric type 1 diabetic patients.

Cardiovascular autonomic neuropathy (CAN) is associated with increased mortality in diabetes. Since CAN often develops in parallel with diabetic nephropathy as a confounder, we aimed to investigate the isolated impact of CAN on cardiovascular disease in normoalbuminuric patients. Fifty-six normoalbuminuric, type 1 diabetic patients were divided into 26 with (+) and 30 without (-) CAN according to tests of their autonomic nerve function. Coronary artery plaque burden and coronary artery calcium score (CACS) were evaluated using computed tomography. Left ventricular function was evaluated using echocardiography. Blood pressure and electrocardiography were recorded through 24 h to evaluate nocturnal drop in blood pressure (dipping) and pulse pressure. In patients +CAN compared with -CAN, the CACS was higher, and only patients +CAN had a CACS >400. A trend toward a higher prevalence of coronary plaques and flow-limiting stenosis in patients +CAN was nonsignificant. In patients +CAN, left ventricular function was decreased in both diastole and systole, nondipping was more prevalent, and pulse pressure was increased compared with -CAN. In multivariable analysis, CAN was independently associated with increased CACS, subclinical left ventricular dysfunction, and increased pulse pressure. In conclusion, CAN in normoalbuminuric type 1 diabetic patients is associated with distinct signs of subclinical cardiovascular disease.

Normal sweat secretion despite impaired growth hormone-insulin-like growth factor-I axis in obese subjects.

Adults with GH deficiency are known to exhibit reduced sweating. Whether sweating capacity is impacted in obese subjects with impaired GH secretion have not previously been investigated. The main objective was to investigate sweat secretion rate and the GH-IGF-I axis in obese subjects before and after weight loss. Sixteen severely obese women (BMI, 40.6 ± 1.1 kg/m(2)) were investigated before and after a diet-induced weight loss. Sixteen age-matched nonobese women served as controls. The obese subjects presented the characteristic decreased GH release, hyperinsulinaemia, increased FFA levels, and impaired insulin sensitivity, which all were normalised after diet-induced weight loss of 30 ± 5 kg. Sweat secretion rates were similar comparing obese and nonobese subjects (78 ± 10 versus 82 ± 9 mg/30 minutes) and sweat secretion did not change after a diet-induced weight loss in obese subjects. We conclude that although obese subjects have markedly reduced GH release and impaired IGF-I levels, sweat secretion rate is found to be normal.