Assessing genetic and environmental influences on epicardial and abdominal adipose tissue quantities: a classical twin study.

BACKGROUND/OBJECTIVES: Various adipose tissue compartments play an important role in the development of cardiometabolic diseases. The quantity of different fat compartments is influenced by genetic and environmental factors. The aim of our study was to evaluate the magnitude of genetic and environmental effects on epicardial, subcutaneous and visceral adipose tissue (EAT, SAT and VAT) quantities in a cohort of adult twin pairs. SUBJECTS/METHODS: In this cross-sectional study we investigated adult twins (57 monozygotic (MZ) and 33 dizygotic (DZ) same-gender twin pairs; 180 twin subjects). We measured EAT volume using electrocardiogram-gated native computed tomography (CT) scan of the heart, and abdominal SAT and VAT areas were quantified between the third and fourth lumbar vertebra on native CT images. We calculated genetic and environmental impact on the size of various adipose tissue compartments by analyzing co-twin correlations in MZ and DZ pairs separately, and furthermore by using genetic structural equation models. RESULTS: In co-twin analysis, MZ twins had stronger correlations than DZ twins for EAT (rMZ=0.81, rDZ=0.32), similar to SAT and VAT quantities (rMZ=0.80, rDZ=0.68 and rMZ=0.79, rDZ=0.48, respectively). In multi-trait model fitting analysis, the overall contribution of genetic factors to EAT, SAT and VAT volumes were 80%, 78% and 70%, whereas environmental factors were 20%, 22% and 30%, respectively. Common pathway model analyses indicated that none of the EAT, SAT and VAT phenotypes was independent of the other two. CONCLUSIONS: Genetic factors have substantial influence, while environmental factors have only a modest impact on EAT volume, abdominal SAT and VAT quantities. There is a considerable amount of common genetic background influencing the quantities of all three adipose tissue compartments.

Is there a connection between postprandial hyperglycemia and IGT related sensory nerve dysfunction?

BACKGROUND AND AIMS: To assess the risk factors for sensory nerve dysfunction in subjects with isolated impaired glucose tolerance (IGT). METHODS AND RESULTS: Seventy-two people with isolated IGT (WHO 1999 criteria) and 39 gender and age-matched healthy volunteers underwent detailed clinical and neurological assessment including quantitative sensory testing using the Neurometer device (current perception threshold measurement on four limbs at three different frequencies). Sensory nerve dysfunction was defined as at least two abnormalities on any frequencies on the upper or lower limbs. Sensory nerve dysfunction was more prevalent among subjects with IGT compared to controls (58.3 vs. 10.3%, OR: 11.23, 95%CI: 3.57-35.35). This association was not influenced by BMI, systolic and diastolic blood pressure, heart rate and autonomic neuropathy (multiple adjusted OR: 13.87, 95%CI: 3.18-60.58), but further adjustment for glycaemic measures abolished the association (OR: 1.58, 95%CI: 0.07-35.68). Assessing the components of glycaemic measures separately, the association between sensory nerve dysfunction and IGT was not affected by HbA1c (OR: 13.94, 95%CI: 1.84-105.5). It was, however, substantially attenuated by fasting plasma glucose (OR: 6.75, 95%CI: 1.33-34.27) while the significance was lost after adjustment for 120 min postload glucose level (OR: 3.76, 95%CI: 0.26-54.10). In the pooled population assessed, independent determinants of sensory nerve dysfunction were older age, 120 min glucose, higher height and cardiovascular autonomic neuropathy at near significance. CONCLUSIONS: Sensory nerve dysfunction amongst subjects with IGT was not explained by cardiovascular covariates, only by glycaemic measures. In addition to 120 min glucose, cardiovascular autonomic neuropathy at borderline significance, age, and height were the independent determinants of sensory nerve dysfunction.

Impact of treatment with saxagliptin on glycaemic stability and ß-cell function in the SAVOR-TIMI 53 study.

AIMS: To study the effects of saxagliptin, a dipeptidyl peptidase-4 inhibitor, on glycaemic stability and ß-cell function in the SAVOR-TIMI 53 trial. METHODS: We randomized 16,492 patients with type 2 diabetes (T2D) to saxagliptin or placebo, added to current antidiabetic medications, and followed them for a median of 2.1 years. Glycaemic instability was defined by: (i) a glycated haemoglobin (HbA1c) increase of ≥ 0.5% post-randomization; (ii) the initiation of new antidiabetic medications for ≥ 3 months; or (iii) an increase in dose of oral antidiabetic medication or ≥ 25% increase in insulin dose for ≥ 3 months. ß-cell function was assessed according to fasting homeostatic model 2 assessment of ß-cell function (HOMA-2ß) values at baseline and at year 2 in patients not treated with insulin. RESULTS: Compared with placebo, participants treated with saxagliptin had a reduction in the development of glycaemic instability (hazard ratio 0.71; 95% confidence interval 0.68-0.74; p < 0.0001). In participants treated with saxagliptin compared with placebo, the occurrence of an HbA1c increase of ≥ 0.5% was reduced by 35.2%; initiation of insulin was decreased by 31.7% and the increases in doses of an oral antidiabetic drug or insulin were reduced by 19.5 and 23.5%, respectively (all p < 0.0001). At 2 years, HOMA-2ß values decreased by 4.9% in participants treated with placebo, compared with an increase of 1.1% in those treated with saxagliptin (p < 0.0001). CONCLUSIONS: Saxagliptin improved glycaemia and prevented the reduction in HOMA-2ß values. Saxagliptin may reduce the usual decline in ß-cell function in T2D, thereby slowing diabetes progression.

Autonomic dysfunction and circadian blood pressure variations in people with impaired glucose tolerance.

AIMS: To assess circadian blood pressure variability in people with impaired glucose tolerance and a healthy control population. METHODS: Seventy-five people with impaired glucose tolerance and 40 healthy volunteers (frequency matched on 10-year age bands and sex) underwent a detailed neurological assessment. Autonomic neuropathy was detected by the five standard cardiovascular autonomic tests and heart rate variability was characterized by the triangle index. Diurnal indices were assessed by 24-h ambulatory blood pressure monitoring. Systolic and diastolic diurnal indices were defined as: (mean daytime blood pressure - mean night-time blood pressure) × 100/mean daytime blood pressure. RESULTS: Mean 24-h systolic and diastolic blood pressure was significantly higher in the group with impaired glucose tolerance compared with the control group [126 ± 12 (mean ± SD) vs. 117 ± 10, 75 ± 7 vs. 71 ± 6 mmHg, both P < 0.05). Systolic and diastolic diurnal indices and heart rate variability triangular index were significantly lower in people with impaired glucose tolerance compared with control subjects (9.1 ± 7.8 vs. 13.2 ± 5.4, 14.5 ± 9.7 vs. 18.4 ± 7.1 mmHg, 28.0 ± 8.4 vs. 39.5 ± 9.3, all P < 0.05). Differences in mean diastolic blood pressure, heart rate variability triangular index and the frequency of non-dippers between those with impaired glucose tolerance and control subjects seemed to be independent of BMI and the presence of cardiovascular autonomic neuropathy, as simultaneous adjustment for BMI and cardiovascular autonomic neuropathy had no major effect on the results. CONCLUSION: Our data suggest that people with impaired glucose tolerance have increased diastolic blood pressure and abnormal circadian blood pressure regulation, independent of obesity and the presence of cardiovascular autonomic neuropathy.

Screening for metabolic syndrome within a minority ethnic group (adult Gypsy people) in Hungary.

BACKGROUND: Metabolic syndrome occurs more often among people living in poorer social conditions. The health status of the largest minority ethnic group in Hungary lags in many aspects behind that of the general population. METHODS: To estimate the prevalence of metabolic syndrome a screening was initiated in the city of Gyor among subjects aged 20-70 years who declared themselves as Gypsy. Subjects with known diabetes and cardiovascular disease were excluded. The diagnosis of metabolic syndrome was based on the ATP-III criteria. RESULTS: Among the 77 individuals screened (35 men, 42 women, age 46.9 ± 10.6 years, x ± SD) diabetes mellitus was found in 14 cases (18.2 %), and pre-diabetes (impaired fasting blood glucose (IFG) or impaired glucose tolerance (IGT) could be diagnosed in further 14 cases (18.2 %). Individual components of the metabolic syndrome occurred as follows: hypertension in 47 subjects (61.0 %), abnormal waist circumference in 40 individuals (51.9 %), abnormal HDL-cholesterol in 39 cases (50.6 %), abnormal triglycerides in 35 individuals (45.5 %) and abnormal fasting blood glucose in 15 subjects (19.5 %). Within the cohort metabolic syndrome could be diagnosed in 39 individuals (50.6 %) without a significant gender difference (males 20/35 = 57.1 %; women: 19/42 = 45.2 %, p>0.05). CONCLUSION: The occurrence of metabolic syndrome and that of glucose intolerance is high among adult Gypsy people in Hungary. In order to recognise cardio-metabolic risks and to prevent their cardiovascular consequences, continuous health promotion and adequate medical care should be provided for the Gypsy population in Hungary (Tab. 5, Ref. 32).

Effects of genetic vs. environmental factors on cardiovascular autonomic function: a twin study.

AIMS: Cardiovascular autonomic function is often assessed in patients with diabetes by measuring heart rate variability and baroreflex sensitivity, the heritability of which is not fully understood. The present study was aimed to determine the effects of genetic and environmental factors on heart rate variability and baroreflex sensitivity in monozygotic and dizygotic adult healthy twin pairs. METHODS: A total of 101 (63 monozygotic, 38 dizygotic) adult twin pairs (n = 202; mean age 44.3 years) were investigated. Anthropometric variables and serum metabolic markers were measured, while environmental characteristics were evaluated by questionnaires. Linear and spectral indices of heart rate variability and baroreflex sensitivity were determined by non-invasive methods. All measurements were adjusted for age and gender (model 1) and for all significantly relevant covariates (model 2). Heritability A-C-E structural equation models were used for characterizing the proportion of additive genetic, shared and unshared environmental influences. RESULTS: Genetic influence of different cardiovascular autonomic indices was estimated between 10.3 and 39.4%, common environmental influence was found between 0.0 and 33.2%, while unshared environmental influence was observed between 60.6 and 81.4% in model 1 analysis. In multivariable-adjusted heritability estimates (model 2), the magnitude of the genetic effects decreased to 0.0%, common environmental influence was nearly unchanged (values between 4.4 and 14.5%), while unshared environmental influence slightly increased (values between 85.5 and 96.5%). CONCLUSIONS: Unshared environmental but not genetic factors have substantial influence on cardiovascular autonomic function, suggesting that appropriate treatment of all modifiable environmental factors is of importance in order to prevent or ameliorate cardiovascular autonomic neuropathy.

Cardiovascular risk factors characteristic for the metabolic syndrome in adult patients with type 1 diabetes.

UNLABELLED: The prevalence rate and clinical significance of the metabolic syndrome in type 1 diabetic patients are not well established. The aim of this study was to estimate the prevalence rate of the metabolic syndrome in adult patients with type 1 diabetes. Patients with type 1 diabetes (n=533; age: 35.6+/-11.6 years; duration of diabetes: 18.0+/-11.1 years; x+/-SD) were consecutively enrolled from 11 diabetes outpatient departments. Data on medical history, actual treatment, anthropometric and laboratory parameters as well as actual blood pressure were registered while eating habits and physical activity were evaluated by standardized questionnaires. The prevalence rate of the metabolic syndrome according to the ATP-III criteria was 31.1% (29.7% in men, 32.7% in women; p>0.05). Using the IDF criteria a higher overall prevalence rate of the metabolic syndrome (36.2%; [32,8% in men, 39.4% in women; p>0.05]) was observed. Comparing type 1 diabetic patients to the general population, the prevalence rate of the metabolic syndrome proved to be significantly higher in each age-group of patients with type 1 diabetes. According to the stepwise logistic regression analysis the metabolic syndrome in type 1 diabetic patients was associated in a decreasing ranking order of significance with waist circumference, serum triglycerides, female gender, antihypertensive medication, HDL-cholesterol, diastolic blood pressure and serum creatinine. CONCLUSIONS: The metabolic syndrome can frequently be detected and is predominantly associated with higher waist circumference in adult patients with type 1 diabetes in Hungary.

Effect of two starting insulin regimens in patients with type II diabetes not controlled on a combination of oral antihyperglycemic medications.

In an open-label, 24-week, parallel-group study, 135 patients inadequately controlled with oral antihyperglycemic medications (OAMs) were treated with maximally tolerated doses of metformin and glibenclamide for at least 8 weeks and then randomized to bedtime neutral protamine Hagedorn (NPH) insulin plus maximally tolerated dose of glibenclamide BID (glib/NPH group) or insulin lispro mix 50 (50% lispro, 50% insulin lispro protamine suspension [ILPS]) pre-breakfast and lispro mix 25 (25% lispro, 75% ILPS) pre-dinner (LM50/LM25 group) (both OAMs discontinued). The LM50/LM25 group had significantly lower 2-hour postprandial BG (both meals combined) compared with glib/NPH after 12 (11.70+/-3.40 mmol/L vs. 13.15+/-2.44 mmol/L, p=0.010) and 24 weeks (11.13+/-3.31 mmol/L vs. 14.46+/-2.93 mmol/L, p =0.0001). Both regimens significantly decreased HbA1c. The reduction was greater with LM50/LM25 (-1.31+/-2% vs. -0.5+/-1.6%; P=0.01). At endpoint, the overall hypoglycemia rate increased with LM50/LM25 and decreased with glib/NPH compared with baseline (0.22+/-0.9 vs. -0.08+/-0.72 episodes/patient/30 days; p =0.037). Treatment with LM50/LM25 compared with glib/NPH in patients with inadequate control on combined OAMs yielded better postprandial and overall glycemic control with a higher rate of hypoglycemia.

Cardiometabolic risk and educational level in adult patients with type 1 diabetes.

A low educational level and a poor socioeconomic status could be associated with increased risk for chronic diseases. The aim of the study was to evaluate the relationship between the educational level and cardiometabolic risk in adult patients with type 1 diabetes (n = 437; age: 38.0 +/- 10.4 years, duration of diabetes: 19.2 +/- 11.1 years; x +/- SD). Educational levels were classified as low [primary school, n = 56 (12.8%)], middle [high school, n = 251 (57.4%)] or high [university, n = 130 (29.7%)]. The prevalence rate of the metabolic syndrome proved to be higher in patients with low versus high educational levels (ATP-III criteria: 42.9 vs. 21.5%, P = 0.0006). Antihypertensive treatment and cardiovascular diseases were more prevalent in patients with low versus high educational level (46.4 vs. 26.2%, P = 0.01; 12.5 vs. 2.3%, P = 0.02; respectively). Overall glycemic control was worse in patients with low versus high educational level (HbA(lc): 8.8 +/- 1.6 vs. 7.9 +/- 1.4%; P = 0.0006). Patients with low versus high educational level differed significantly regarding smoking habits (smokers: 28.6 vs. 11.6%; P = 0.01) and regular physical activity (5.4 vs. 33.1%; P = 0.0001). Higher prevalence rate of certain cardiometabolic risk factors was associated with low educational level in middle-aged type 1 diabetic patients with relatively long duration of diabetes; therefore, these patients should have priority when preventing cardiovascular complications.

Impairment of the NO/cGMP pathway in the fasting and postprandial state in type 1 diabetes mellitus.

The assessment of the postprandial state in diabetes mellitus has gained importance due to postprandial hyperglycemia being considered as an independent risk factor for cardiovascular disease. Hyperglycemia may contribute to vascular dysfunction through the alteration of the nitric oxide/cyclic guanosine monophosphate (NO/cGMP) pathway. The authors assessed the NO/cGMP pathway in the fasting and postprandial state in 20 type 1 diabetic patients (age: 34.1 +/- 2.6 years, body mass index (BMI): 24.1 +/- 1.3 kg/m (2), duration of diabetes: 16 +/- 2.2 years, HbA (1C): 8.3 +/- 0.4 %, [x +/- SEM], 10 without, 10 with late complications) and 20 matched control subjects (age: 39.7 +/- 1.9 years, BMI: 25.3 +/- 1.1 kg/m (2)). In the fasting state NO end product (nitrite/nitrate) levels did not differ between the diabetic and control group, cGMP levels were found to be significantly lower in the diabetic group (2.5 +/- 0.2 vs. 4.6 +/- 0.6 nmol/l, p = 0.01). A higher level of lipid peroxidation end products (TBARS) was found in diabetic subjects (6.7 +/- 0.4 vs. 5.0 +/- 0.3 micro mol/l, p = 0.004). The diabetic subgroup without late complications had significantly higher nitrite/nitrate levels compared to the patients with complications (57.8 +/- 6.6 vs. 30.4 +/- 4.3 micro mol/l, p = 0.006), their TBARS and cGMP levels were similar. The control subjects responded to the test meal with an increase in the cGMP levels (4.6 +/- 0.6 to 5.5 +/- 0.6 nmol/l, p = 0.02), while in the diabetic group no change was detected. Postprandial nitrite/nitrate levels decreased in both groups, they were significantly lower in the diabetic group. There was no difference between postprandial nitrite/nitrate, cGMP, or glucose levels in the diabetic subgroups. Postprandial glucose levels showed a significant negative correlation with cGMP levels in the diabetic group (r = - 0.50, p = 0.02). The results suggest that in subjects with type 1 diabetes mellitus NO might have an impaired ability to induce cGMP production in the fasting state prior to the development of late specific complications or microalbuminuria under hyperglycemic conditions. Postprandial hyperglycemia is suggested to interfere with endothelial NO action, as shown by the decreased nitrite/nitrate and unchanged cGMP plasma levels in the diabetic group. The impairment of the NO/cGMP pathway both in the fasting and postprandial state that was shown in patients without diabetic complications may be an early sign of hyperglycemia induced vascular damage in type 1 diabetes mellitus.

Intima-media thickness of the carotid arteries in subjects with hyperinsulinaemia (insulin resistance).

The metabolic syndrome is characterised by hyperinsulinaemia (insulin resistance) leading to an increased risk of atherosclerotic cardiovascular diseases. Carotid intima-media thickness (IMT) can be easily measured to detect early atherosclerosis. In order to evaluate the clinical characteristics of the metabolic syndrome a screening procedure was performed and carotid IMT was determined by high-resolution B-mode ultrasonography in a cohort of middle-aged (40-60 years) subjects who proved to be hyperinsulinaemic [fasting plasma insulin >15 microU/ml and/or post-prandial (120 min) insulin > 45 microU/ml; n = 91; men/women: 35/56; homeostasis model assessment (HOMA)-index: 6.42 +/- 3.65; x +/- SD]. Subjects known to have diabetes were not involved. Subjects were divided into subgroups according to the stages of glucose intolerance (normal glucose tolerance, n = 46; impaired glucose tolerance, n = 26; diabetes mellitus, n = 19). As controls, age- and sex-matched non-diabetic and non-hyperinsulinaemic subjects (n = 20; HOMA-index: 2.09 +/- 0.85) were investigated. The values of IMT of the internal carotid arteries were higher in hyperinsulinaemic subjects than in controls (0.93 +/- 0.39 mm vs 0.57 +/- 0.13 mm,p < 0.001), whereas the lumen diameter proved to be smaller than in control subjects (5.04 +/- 0.75 mm vs 5.45 +/- 0.71 mm; p < 0.05). In hyperinsulinaemic subjects only a trend of increasing IMT values and that of decreasing lumen diameter of the internal carotid arteries were observed when subgroups classified according to the stages of glucose intolerance were compared. No significant changes in IMT or lumen diameter of the common carotid arteries were observed. Early and asymptomatic signs of atherosclerosis could be detected in middle-aged subjects who proved to be hyperinsulinaemic in a screening procedure. The prevention of clinically manifest cardiovascular diseases in these subjects could be of great importance.

Effect of indapamide SR on microalbuminuria--the NESTOR study (Natrilix SR versus Enalapril Study in Type 2 diabetic hypertensives with micrOalbuminuRia)--rationale and protocol for the main trial.

In type 2 diabetic hypertensive patients, microalbuminuria can be due to hypertension and/or diabetic nephropathy. Angiotensin-converting enzyme (ACE) inhibitors act preferentially on microalbuminuria due to diabetic nephropathy. The objective is to demonstrate the efficacy of a thiazide-like diuretic, indapamide sustained release (SR), at reducing microalbuminuria in hypertensive type 2 diabetic patients in comparison with an ACE inhibitor, enalapril. The study is an international multicentre, 12-month, randomized, double-blind, controlled, two parallel group study of type 2 diabetic patients with hypertension (140 mmHg < or = systolic blood pressure <180 mmHg and diastolic blood pressure <110 mmHg) and microalbuminuria. Intervention is after a 4-week placebo period, patients with microalbuminuria > or = 20 and < or = 200 microg/min are randomized to indapamide SR 1.5 mg or to enalapril 10 mg once a day for a one-year treatment period. An additional label treatment by amlodipine 5-10 mg (1st step) and atenolol 50-100 mg (2nd step) a day is permitted after 6 weeks of treatment based upon blood pressure response. The main outcome measures are microalbuminuria expressed as urinary albumin to creatinine ratio, albumin fractional clearance, and albumin excretion rate evaluated on overnight urine collections. Secondary criteria are supine and standing systolic, diastolic and mean blood pressure; and biological and clinical safety. This study will complete the knowledge of the efficacy of indapamide SR in hypertension and target organ damage and will provide valuable information on the management of type 2 diabetic hypertensives with microalbuminuria.

Clinical consequences of cardiovascular autonomic neuropathy in diabetic patients.

A wide range of clinical consequences of cardiovascular autonomic neuropathy (CAN) can be observed in diabetic patients and contributes to the clinical picture of the diabetic heart. Resting heart rate and cardiovascular reflexes as well as circadian heart rate variability may be altered by CAN in diabetes. Moreover, blood pressure is also influenced by sympathovagal imbalance. Postural hypotension is a clinical characteristic in diabetic subjects with CAN. Painless myocardial infarction, ischaemia and left ventricular dysfunction are also observed in some cases. Impairment of cardiac parasympathetic and sympathetic innervation as well as QT-interval prolongation may play a partial role in the pathogenic mechanism of sudden unexpected death in diabetic patients. The risk of surgical intervention and that of anaesthesia are increased due to abnormal cardiovascular reactions. Clinical symptoms and signs of CAN should be assessed as severe diabetic complication and the therapy is difficult in some cases. Taken together, symptoms and signs of CAN carry a poor prognosis in diabetic patients.

Practical aspects of measuring microalbuminuria in diabetic patients.

The importance of measuring microalbuminuria is well established; however, controversy still exists regarding the type of urine specimen to be used for detecting early renal impairment of diabetic patients. To evaluate practical aspects, albumin concentration and albumin/creatinine ratio of first void urine samples as well as urinary albumin excretion in timed specimens were determined by immunoturbidimetric method 3 times within 3 weeks in 192 adult diabetic patients (136 men, 56 women; Type 1/Type 2 diabetes: 90/102; age: 51.4+/-10.8 yr; duration of diabetes: 15.3+/-9.1 yr; body mass index: 27.9+/-4.6 kg/m2; HbA1c: 8.54+/-1.46%; actual blood pressure: 138+/-14/82+/-8 mmHg; serum creatinine: 94+/-20 pmol/l; x+/-SD). According to the urinary albumin excretion values one-third of patients (31.2%-30.7%-34.4%) were normoalbuminuric (<30 mg/24 hr), more than half of the patients (55.8%-57.3%-53.6%) proved to be microalbuminuric (30-300 mg/24 hr), while the remaining group of patients (13.0%-12.0%-12.0%) was macroalbuminuric (>300 mg/24 hr). Comparing the results of successive measurements, good correlation was found between the same laboratory values (urinary albumin excretion: kappa=0.64, kappa=0.67; urinary albumin concentration: kappa=0.60, kappa=0.62; albumin/creatinine ratio: kappa=0.54, kappa=0.61; first vs second and second vs third measurements, respectively). The percentage of patients being in the same range of albuminuria (ie normo-, micro- or macroalbuminuria) at successive measurements was 79.7-81.2% with urinary albumin excretion values, 77.1-77.6% with urinary albumin concentration and 74.5-78.6% with albumin/creatinine ratio. Good correlation was found between urinary albumin excretion and urinary albumin concentration (kappa=0.54; 0.54; 0.57) and nearly the same correlation was observed between urinary albumin excretion and albumin/creatinine ratio (kappa=0.49; 0.47; 0.54) at the three consecutive measurements (n=192). Using values of urinary albumin excretion for comparison at all measurements, 79.3% sensitivity and 69.5% specificity were found for urinary albumin concentration, whereas 74.6% sensitivity and 68.8% specificity were documented for albumin/creatinine ratio. Beside the standard measurement of urinary albumin excretion in timed urine samples, the use of the more convenient morning urinary spot collection could also provide useful results (urinary albumin concentration or albumin/creatinine ratio) for detecting early renal involvement in diabetic patients.

[Advanced microangiopathic complications at the diagnosis of diabetes mellitus]. / Súlyos microangiopathiás szövódmények a diabetes mellitus felismerésekor.

A case of a 59-year-old male patient with advanced microangiopathic complications at the diagnosis of diabetes mellitus is reported. The patient was referred to ophthalmological investigation due to progressive loss of visual acuity. Although diabetes mellitus was not known, proliferative diabetic retinopathy with significant visual loss was found at fundus examination. Not only newly diagnosed diabetes mellitus (initial fasting blood glucose 19.0 mmol/, HbA1c: 11.6%) but the presence of advanced sensory, motor and autonomic diabetic neuropathy (nervus peroneus motor conduction velocity: 32.1 m/s, nervus suralis sensory conduction velocity could not be detected, postural decrease in systolic blood pressure: 20 mmHg, beat-to-beat variation 6 beats/min, 30:15 ratio 1.03) as well as signs of advanced diabetic nephropathy (daily urinary protein excretion: 1.2-5.7 g, serum creatinine value: 101 mumol/l, sitting blood pressure: 150/100-180/100 mmHg) could be documented by further investigations at Medical Department. Avoiding short-term strict metabolic control insulin therapy was initiated and adequate long-term diabetic control was achieved later (HbA1c: 6.5-6.2%). In order to classify the diabetes, repeated measurements of serum C-peptide, ICA, GADA and IA2-antibodies were performed and type 2 diabetes was diagnosed. After a transient deterioration the proliferative retinopathy remained unchanged. Although laser photocoagulation was performed, no improvement in the visual acuity could be achieved. Only a minor improvement of neurological alterations was documented by repeated electrophysiological investigation at follow-up. Although the antihypertensive treatment (ACE-inhibitor drug in combination with calcium channel blocker) resulted in a significant decrease of elevated blood pressure, only a transient improvement of proteinuria could be achieved. Despite regular control, the advanced microangiopathic complications of diabetes mellitus carry poor prognosis.

[Thiazolidinediones--a new class of oral antidiabetic drugs]. / Tiazolidindionok--az oralis antidiabeticumok új hatástani csoportja.

The discovery of a new class of oral antidiabetic drugs was stimulated by difficulties with the treatment currently available for patients with type 2 diabetes mellitus. Thiazolidinediones can lower blood glucose values due to their special insulin-sensitiser effect. In this way, these drugs seem to be very effective in the treatment of type 2 diabetic patients with characteristics of metabolic syndrome. The intracellular action caused by thiazolidinediones differs markedly from that of other oral antidiabetic drugs available. Apart from antihyperglycaemic effect, thiazolidinediones have further beneficial effects in experimental diabetes which require corroboration by clinical studies. Troglitazone was the first drug which reached the market. Unfortunately, this drug was withdrawn soon due to its hepatotoxicity. Rosiglitazone proved to be much safer in clinical studies. Pioglitazone is being tested nowadays in clinical studies. Thiazolidinediones have been already listed among oral antidiabetic drugs in international therapeutical guidelines. Nevertheless, further clinical studies and experiences are needed to determine the final exact indication of thiazolidinediones for the treatment of type 2 diabetic patients.

[Plasma homocysteine levels in hyperinsulinemic patients]. / Hyperinsulinaemiás egyének plazma homociszteinszintje.

In order to evaluate the clinical characteristics of metabolic syndrome, a screening procedure was performed and in a cohort of middle-aged (40-60 years) hyperinsulinaemic (fasting plasma insulin > 15 microU/ml) and/or postprandial [120 min after 75 g glucose load] insulin > 45 microU/ml) subjects (n = 91; men/women: 38/53; age mean +/- SD 47.6 +/- 4.3 years; body mass index: 34.6 +/- 4.9 kg/m2; waist-hip ratio: 0.92 +/- 0.07; actual blood pressure 146 +/- 16/87 +/- 9 mmHg; fasting insulin: 24.2 +/- 11.3 microU/ml; postprandial insulin 125.5 +/- 103.8 microU/ml; serum LDL-cholesterol: 3.73 +/- 1.09 mmol/l; HDL-cholesterol: 1.12 +/- 0.30 mmol/l; triglycerides: 2.97 +/- 2.38 mmol/l; uric acid 279 +/- 79 mumol/l) plasma fasting homocysteine, vitamin B12 and folic acid levels were simultaneously determined. The values were separately evaluated according to the stages of glucose tolerance (normal glucose tolerance [n = 47]; impaired glucose tolerance [n = 24] and diabetes mellitus [n = 20]). Laboratory normal values were determined in 47 healthy subjects (control group, age: 45.0 +/- 7.8 years, men/women: 19/28). There was no significant difference between hyperinsulinaemic and control subjects regarding plasma homocysteine (9.28 +/- 3.81 mumol/l vs. 9.63 +/- 2.70 mumol/l), folic acid (8.5 +/- 5.9 ng/ml vs. 7.5 +/- 2.1 ng/ml) and vitamin B12 levels (423 +/- 141 pg/ml vs. 356 +/- 121 pg/ml). Plasma homocysteine levels were significantly (p < 0.001) higher in hyperinsulinaemic men than women (11.34 +/- 4.72 mumol/l [n = 38] vs. 7.86 +/- 2.13 mumol/l [n = 53]). There was no significant difference between subgroups classified according to the stages of glucose tolerance in hyperinsulinaemic groups. Plasma homocysteine values exceeding the upper limit of normal range (> 12.45 mumol/l) were detected at a similar prevalence rate in control (4/47 = 8.5%) and in hyperinsulinaemic subjects (10/91 = 10.9%). A weak but statistically significant correlation was found between plasma homocysteine values and age of subjects (r = 0.222; p < 0.05) whereas a stronger correlation was documented between plasma homocysteine and serum creatinine values (r = 0.658; p < 0.001) in hyperinsulinaemic groups (n = 91). Plasma homocysteine values independently from the stages of glucose tolerance are not elevated in hyperinsulinaemic subjects. Hyperhomocysteinaemia is not a characteristic feature of hyperinsulinism suggesting that plasma homocysteine levels are of no considerable importance in the complex pathomechanism of atherosclerosis at early stages of metabolic syndrome.