The predictive capability of the glycaemic response to spaghetti in non-insulin dependent (NIDDM) and insulin dependent (IDDM) diabetic subjects

To evaluate the predictive capability of the postprandial blood glucose response after consumption of a starch-rich meal, we compared the glycaemic effects of spaghetti (60 g) taken alone and with bolognese sauce (167 g). The study was carried out in both NIDDM (n = 6) and IDDM (n = 6) subjects. The latter had achieved normoglycaemia 120 min prior to the test meal by means of an artificial pancreas (Biostator) which provided constant insulinaemia during the observation period of 4 h. We found that the areas of blood glucose (above basal) were identical irrespective of whether spaghetti was taken alone or as part of a mixed meal in both NIDDM (484 +/- 154 mmol l-1 240 min-1 vs. 393 +/- 126 mmol l-1 240 min-1) and IDDM subjects (610 +/- 143 mmol l-1 240 min-1 vs. 770 +/- 135 mmol l-1 240 min-1). The insulin levels were identical in the IDDM diabetics. By contrast, the mixed meal caused a more marked insulinaemic response than spaghetti per se in the NIDDM subjects (3187 +/- 637 mU l-1 240 min-1 vs. 1940 +/- 235 mU l-1 240 min-1; P less than 0.05). In conclusion, the predictive capability of the glycaemic response to spaghetti was good in both IDDM and NIDDM diabetic subjects, at least under the conditions of the present study.     

Autoantibodies to the islet antigen ICA 69 occur in IDDM and in rheumatoid arthritis

Summary Islet cell antigen (ICA) 69 is a newly-recognized islet cell antigen to which autoantibodies have been observed in prediabetic relatives of patients with insulin-dependent-diabetes mellitus (IDDM). Here we extend the earlier analysis of ICA 69 antibodies to patients with recent-onset IDDM and to patients with other immune-mediated diseases. ICA 69 antibodies were determined by Western blot using an affinity purified recombinant fusion protein of ICA 69 and maltose binding protein. ICA 69 antibody quantities were determined as titres using a titration curve of a standard serum as reference. Mean logarithmic ICA 69 antibody titres were 3.4 (±1.4) in 99 patients with acute IDDM compared to 2.8 (±0.9) in 49 healthy blood donors (p<0.001). A higher mean ICA 69 antibody titre of 4.1 (±0.8) was observed in 16 patients with rheumatoid arthritis in comparison to acute IDDM (p<0.01) and healthy control subjects (p<0.001). The percentage of sera with ICA 69 antibody titres above the 2 SD level of normal subjects was 21% in IDDM, 31% in rheumatoid arthritis and 6% in healthy blood donors. None of the patients with autoimmune thyroid disease (n=20), inflammatory bowel disease (n=9) or multiple sclerosis (n=7) had elevated ICA 69 antibodies. In IDDM, presence of ICA 69 antibodies persisted and the titre remained the same over 18 months of follow-up. The relationship of ICA 69 antibodies to islet cell antibodies (ICA) or insulin autoantibodies (IAA) was tested. The production of ICA 69 antibodies was not associated in diabetic patients with the presence of any of the two other autoantibodies. In conclusion, this study describes ICA 69 antibodies in acute IDDM and finds them to be independent of other islet autoantibodies. In addition ICA 69 is a target of humoural autoimmunity not only in IDDM but also in rheumatoid arthritis.Abbreviations IDDM Insulin-dependent diabetes mellitus - ICA islet cell antibodies - IAA insulin autoantibodies - RA rheumatoid arthritis - RF rheumatoid factor - GAD 65 glutamic acid decarboxylase - SMS stiff-man syndrome     

Decreased hepatic glucagon responses in Type 1 (insulin-dependent) diabetes mellitus

Summary The effect of glucagon infusion on hepatic glucose production during euglycaemia was evaluated in seven Type 1 (insulin-dependent) diabetic patients and in ten control subjects. In the diabetic subjects normoglycaemia was maintained during the night preceding the study by a variable intravenous insulin and glucose infusion. During the study endogenous insulin secretion was suppressed by somatostatin (450 g/h) and replaced by insulin infusion (0.15 mU·kg^–1·min^–1). ³H-glucose was infused for isotopic determination of glucose turnover. Plasma glucose was clamped at 5 mmol/1 for 2 h 30 min and glucagon (1.5 ng· kg^–1·min^–1) was then infused for the following 3 h. Hepatic glucose production and glucose utilisation were measured during the first, second and third hour of the glucagon infusion. Basal hepatic glucose production (just prior to glucagon infusion) was similar in diabetic (1.2±0.3 mg·kg^–1·min^–1) and control (1.6±0.1 mg·kg^–1·min^–1) subjects. In diabetic patients hepatic glucose production rose slowly to 2.1±0.5 mg·kg^–1·min^–1 during the first hours of glucagon infusion and stabilized at this level (2.4±0.5 mg·kg^–1·min^–1) in the third hour. In control subjects hepatic glucose production increased sharply to higher levels than in the diabetic subjects (3.4±0.3 mg·kg^–1·min^–1) during the first and second hour of glucagon infusion (p<0.05) and then gradually fell (2.9±0.4 mg·kg^–1·min^–1) during the third hour. In conclusion, when stimulated with glucagon at a physiologic plasma concentration diabetic patients had 1) an overall reduced hepatic glucose production response and 2) an abnormal sluggish response pattern. These abnormalities may imply inappropriate counter-regulation following a hypoglycaemic episode.     

Physiological response to postural change during mild hypoglycaemia in patients with IDDM

Summary It has been suggested that patients with insulin-dependent diabetes mellitus may be less aware of impending hypoglycaemia when lying than standing. We have studied the effect of posture and duration of hypoglycaemia on symptoms and physiological responses in 10 men with insulin-dependent diabetes. A standard tilting protocol was used (supine, 50, 90 headup, and return to supine, 5 min at each position). At one visit patients were tilted before, 10 min after and 40 min after achieving hypoglycaemia (blood glucose 2.5 mmol/l), and at another visit were tilted after euglycaemia (5.0 mmol/l) using a hyperinsulinaemic clamp. At each position, hormonal and physiological responses and symptoms (using visual analogue scales) were recorded. After 10 min of hypoglycaemia, adrenaline was significantly higher when 90 headup compared with supine (mean [±SEM] 6.26 [±1.88] vs 1.68 [±0.4] nmol/l; p<0.05), and fell significantly (to 2.46 [±0.65] nmol/l; p<0.05) when returned to supine; sweating, symptom score and blood pressure followed a similar pattern. After 40 min of hypoglycaemia a similar effect of standing was seen on sweating, adrenaline and blood pressure but symptoms did not increase. Five patients underwent two further periods of hypoglycaemia, remaining supine or standing throughout. Face skin blood flow (p<0.05) and temperature (p=0.05) decreased when standing was maintained compared with lying. In conclusion, standing increases awareness of early hypoglycaemia and modifies many of the physiological changes. This increase in awareness is lost if hypoglycaemia is prolonged.Abbreviations IDDM Insulin-dependent diabetes mellitus - ANOVA analysis of variance - bpm beats per min     

Elevated levels of soluble E-selectin in patients with IDDM and NIDDM: relation to metabolic control

Summary The adhesion of leucocytes to the endothelium, an early step in atherogenesis, is mediated by cell adhesion molecules. In this study we evaluated the concentration of soluble adhesion molecules in patients with insulin-dependent (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM) and studied its relation to glycaemic control. Soluble adhesion molecules E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) were measured in 31 diabetic patients (18 with IDDM and 13 with NIDDM), 20 hyperlipoproteinaemic patients (10 with type IIa and 10 with type IIb) and 20 healthy subjects. Increased E-selectin concentrations were found in the patients with IDDM and NIDDM and in the hyperlipoproteinaemic patients when compared to the control subjects (p<0.01 for all the groups). ICAM-1 was found to be elevated only in the patients with NIDDM (p<0.01). No significant differences in VCAM-1 concentration were found in the different groups of subjects. The concentration of plasma E-selectin was positively correlated with the glycated haemoglobin (r=0.54, p<0.01) in patients with IDDM and NIDDM. In the same patients E-selectin was not related to the concentrations of plasma lipids in spite of the fact that it was found to be elevated in hyperlipoproteinaemic subjects. The results though preliminary suggest that in diabetic patients the concentration of soluble adhesion molecules and especially of E-selectin may be related to metabolic control.Abbreviations IDDM insulin-dependent diabetes mellitus - NIDDM non-insulin-dependent diabetes mellitus - ICAM-1 intercellular adhesion molecule-1 - VCAM-1 vascular adhesion molecule-1 - AGE advanced glycation end products     

Thermoregulatory responses to hyperinsulinaemic hypoglycaemia and euglycaemia in IDDM

Summary In healthy subjects hypoglycaemia causes a fall in body temperature through increased sweating and limb blood flow, and despite increased metabolic heat production. We studied thermoregulatory responses to hyperinsulinaemic (100 mU · m^–2 · min^–1) (a) hypoglycaemia (2.5 mmol/l) and (b) euglycaemia (4.5 mmol/l) in insulin-dependent diabetic men of short (<5 years) and long (>5 years) diabetes duration. Plasma noradrenaline (p<0.0001), metabolic rate (p <0.005), heart rate (p<0.0001) and skin blood flow (p<0.05) increased during hypoglycaemia and euglycaemia with a greater rise in noradrenaline during the former (p<0.05). Plasma adrenaline (p<0.005), forearm blood flow (p<0.05) and systolic blood pressure (p<0.02) increased and diastolic blood pressure decreased (p<0.005) during hypoglycaemia, with greater changes in adrenaline (p<0.05) and diastolic blood pressure in patients of short diabetes duration. Only two patients (diabetes duration < 2 years) sweated appropriately, while body temperature changed minimally in the two groups of patients. In summary, thermoregulatory responses to hypoglycaemia are impaired in IDDM due to attenuated sweating and adrenomedullary responses.Abbreviations IDDM Insulin-dependent diabetes mellitus - ANOVA analysis of variance - BMI body mass index     

Normalization of hepatic glucose regulation despite systemic insulin delivery. Studies in patients with pancreatic transplantation for Type 1 (insulin-dependent) diabetes mellitus

Summary With current surgical techniques for pancreatic transplantation, the graft is anastomosed to the iliac vessels, resulting in delivery of insulin to the systemic circulation rather than to the portal vein as in healthy man. The possible influence of the altered route of insulin delivery on the regulation of splanchnic glucose metabolism was studied in four patients with Type 1 (insulin-dependent) diabetes mellitus at 6–19 months after combined pancreatic and kidney transplantation. Four non-diabetic, age-matched renal transplant recipients and two groups of age-matched healthy subjects served as controls. The studies were carried out in the basal state and during two rates of intravenous glucose infusion (2 and 4 mg · kg^–1 · min–1). Fasting arterial glucose and splanchnic glucose output was similar in all groups. Basal hyperinsulinaemia was present in pancreatic graft recipients compared to healthy subjects. During low rate intravenous glucose infusion splanchnic glucose output decreased to a similar extent in all groups. With the higher glucose infusion rate (4 mg · kg^–1 · min^–1) a net glucose uptake was observed which was similar in all three groups. Peripheral glucose uptake was unchanged at the lower glucose infusion rate but increased by 45–55% at the higher rate. It is concluded that despite systemic insulin delivery from a heterotopic pancreatic graft, hepatic glucose metabolism appears normal both in the post-absorptive state and in response to glucose-stimulated endogenous insulin secretion. Portal insulin delivery is thus not necessary for normal hepatic glucose metabolism in the Type 1 diabetic patient.     

Time-dependent inhibition of insulin release: suppression of the arginine effect by hyperglycaemia

Summary Brief stimulation of the pancreas with arginine causes a refractory state which reduces the insulin response to subsequent stimulations (time-dependent inhibition). In control subjects, a pair of arginine injections (75mg/kg) at a 30-min interval resulted in 20% reduction of peak and integrated insulin responses to the second injection. In Type 2 (non-insulin-dependent) diabetic patients and in obese subjects, the inhibitory effect of repeated arginine stimuli was abolished. Healthy subjects were made acutely hyperglycaemic (9.3±0.3 mmol/l) by the glucose clamp technique. This induced a three- to fivefold greater insulin response to arginine. Compared to the response of diabetic subjects with similar hyperglycaemia, the control subjects secreted four to nine times more insulin. When the arginine stimulation was repeated 30 min later, no inhibition was observed, the second insulin response being instead augmented 1.5- to 1.8-fold. We conclude that (1) the insulin response to arginine is markedly reduced in Type 2 diabetes; (2) arginine-induced time-dependent inhibition of insulin release is abolished in patients with minimal to moderate hyperglycaemia; (3) this is probably due to the acute synergistic action of glucose and arginine on the B cell; (4) time-dependent inhibition of insulin release may be a protective mechanism against insulin oversecretion following repetitive stimulation of the pancreas; its abolition in hyperglycaemic states may be a compensatory mechanism, allowing substantial increases in insulin output.     

Very low density lipoprotein subfraction abnormalities in IDDM patients: any effect of blood glucose control?

Summary Normolipidaemic insulin-dependent diabetic (IDDM) patients are characterized by an increase in the smaller VLDL particles, considered to be the most atherogenic. Since blood glucose control is one of the main regulators of lipid metabolism in diabetic patients, it could influence the shift in the distribution of VLDL subfractions towards smaller particles. To evaluate this possibility, VLDL subfractions, post-heparin lipoprotein lipase and hepatic lipase activities have been evaluated in male IDDM patients with either unsatisfactory blood glucose control (group 1, HbA_1c>8%, n=18) or good blood glucose control (group 2, HbA_1c<8%, n=16) and in 16 normoglycaemic individuals. The three groups were comparable for sex, age, body mass index, and plasma lipid levels. Three VLDL subfractions (large, Svedberg flotation unit (Sf) 175–400; intermediate, Sf 100–175; small, Sf 20–100) were separated by density gradient ultracentrifugation and analysed for cholesterol, triglyceride, and phospholipid levels. When compared to control subjects both groups of IDDM patients showed a clear shift in VLDL subfraction distribution with a significant increase in the proportion of small VLDL (group 1; 49±2%; p<0.005; group 2: 51±3%, p<0.01; control subjects 40±2%) (mean ± SEM) in relation to total VLDL. By contrast, the absolute lipid concentration of small VLDL was higher only in group 1, compared to control subjects (35±4 vs 27±3 mg/dl, p=0.05). Post-heparin hepatic lipase activity was significantly reduced in both IDDM groups (group 1: 254±19 mU/ ml, p<0.05; group 2: 202±19 mU/ml, p<0.005; control subjects 317±31 mU/ml). In conclusion, normolipidaemic IDDM patients show an increase in the smallest VLDL, whatever their degree of blood glucose control. However, this abnormality may be clinically relevant only in patients with unsatisfactory blood glucose control, since absolute lipid concentration of these potentially atherogenic particles is only increased in this group.Abbreviations IDDM Insulin-dependent diabetes mellitus - VLDL very low density lipoprotein - LPL lipoprotein lipase - HL hepatic lipase     

Double blind trial of nicotinamide in recent-onset IDDM (the IMDIAB III study)

Summary Nicotinamide has been recently introduced, in addition to intensive insulin therapy for patients with recent-onset insulin-dependent diabetes mellitus (IDDM) to protect beta cells from end-stage destruction. However, available data are conflicting. A double blind trial in 56 newly-diagnosed IDDM patients receiving nicotinamide for 12 months at a dose of 25 mg/kg body weight or placebo was designed in order to determine whether this treatment could improve the integrated parameters of metabolic control (insulin dose, glycated haemoglobin and C-peptide secretion) in the year after diagnosis. In addition to nicotinamide or placebo, patients received three to four insulin injections daily to optimize blood glucose levels. Patients treated with nicotinamide or placebo received similar doses of insulin during follow-up and 1 year after diagnosis with comparable glycated haemoglobin levels (6.7 ± 1.8 % nicotinamide vs 7.1 ± 0.6 % placebo). Basal and glucagon stimulated C-peptide secretion detectable at diagnosis were similarly preserved in the course of 12 months follow-up both in nicotinamide and placebo treated patients. No adverse effects were observed in patients receiving nicotinamide. When age at diagnosis was taken into account, nicotinamide treated older patients ( > 15 years of age) showed significantly higher stimulated C-peptide secretion than placebo treated patients (p < 0.02). These results suggest that nicotinamide can preserve and improve stimulated beta-cell function only in patients diagnosed after puberty. We conclude that in these patients nicotinamide can be added to insulin at the time of disease diagnosis to maintain and possibly improve residual beta-cell function. However, further studies on patients diagnosed after puberty are needed to confirm whether nicotinamide can be considered an additional tool to insulin in early-onset IDDM. [Diabetologia (1995) 38: 848–852] Received: 20 June 1994 and in final revised form: 20 January 1995     

Captopril reduces the risk of nephropathy in IDDM patients with microalbuminuria

Summary In insulin-dependent diabetes mellitus (IDDM), microalbuminuria predicts renal and cardiovascular disease. We report a combined analysis of 235 normotensive IDDM patients with microalbuminuria who participated in two 24-month double-blind, randomised, placebo-controlled trials to assess the effects of captopril 50 mg twice daily on the progression to overt clinical albuminuria. Of the 225 patients who were evaluable on an intent to treat basis, 25 of 114 placebo-treated patients (21.9%) and 8 of 111 captopril-treated patients (7.2%) progressed to persistent clinical albuminuria. The risk of progression over 24 months was significantly reduced by captopril (p=0.004) with a risk reduction of 69.2% (95% confidence interval (CI): 31.7 to 86.1%). This degree of risk reduction remained at the same level (62.9% [16.1–83.6%], p=0.017) after adjustment for differences in time-varying mean arterial blood pressure. Albumin excretion rate increased by an average of 14.2% [3.1–26.5%] per year in the placebo-treated group compared with a reduction of 9.6% [–18.6–0.4%] per year in the captopril-treated group (p=0.002). The rate of fall of creatinine clearance tended to be faster in the placebo-treated group than in the captopril-treated group (–6.4 [–10.2––2.5] vs –1.4 [–5.3–2.6] ml · min^–1 · 1.73 m^–2, p=0.07). Baseline albumin excretion rate (p<0.0001) and glycated haemoglobin (p=0.03) were independent predictors of progression to clinical albuminuria and changes in mean arterial blood pressure (p=0.02) and serum cholesterol level (p=0.003) were significantly associated with percentage changes in albumin excretion rate. Captopril reduces the risk of progression to overt nephropathy in IDDM patients with microalbuminuria, an effect partly independent of its blood pressure-lowering effects.Abbreviations ACE Angiotensin converting enzyme - IDDM insulin-dependent diabetes mellitus - GFR glomerular filtration rate - C captopril - P placebo - AER albumin excretion rate - MAP mean arterial pressure Corresponding author: Professor G.C. Viberti, Unit for Metabolic Medicine, United Medical and Dental Schools of Guy's and St. Thomas' Hospitals, Guy's Hospital, London SE1 9RT, UKMembership of the Study Group is listed in the Acknowledgement section     

Lack of suppression of glucagon contributes to postprandial hyperglycemia in subjects with type 2 diabetes mellitus

We tested the hypothesis that a lack of suppression of glucagon causes postprandial hyperglycemia in subjects with type 2 diabetes. Nine diabetic subjects ingested 50 g glucose on two occasions. On both occasions, somatostatin was infused at a rate of 4.3 nmol/kg x min, and insulin was infused in a diabetic insulin profile. On one occasion, glucagon was also infused at a rate of 1.25 ng/kg x min to maintain portal glucagon concentrations constant (nonsuppressed study day). On the other occasion, glucagon infusion was delayed by 2 h to create a transient decrease in glucagon (suppressed study day). Glucagon concentrations on the suppressed study day fell to about 70 ng/L during the first 2 h, rising thereafter to approximately 120 ng/L. In contrast, glucagon concentrations on the nonsuppressed study day remained constant at about 120 ng/L throughout. The decrease in glucagon resulted in substantially lower (P < 0.001) glucose concentrations on the suppressed compared with the nonsuppressed study days (9.2+/-0.7 vs. 10.9+/-0.8 mmol/L) and a lower (P < 0.001) rate of release of [14C]glucose from glycogen (labeled by infusing [1-14C]galactose). On the other hand, flux through the hepatic UDP-glucose pool (and, by implication, glycogen synthesis), measured using the acetaminophen glucuronide method, did not differ on the two occasions. We conclude that lack of suppression of glucagon contributes to postprandial hyperglycemia in subjects with type 2 diabetes at least in part by accelerating glycogenolysis. These data suggest that agents that antagonize glucagon action or secretion are likely to be of value in the treatment of patients with type 2 diabetes.     

Estimates of Krebs cycle activity and contributions of gluconeogenesis to hepatic glucose production in fasting healthy subjects and IDDM patients

Summary Normal subjects, fasted 60 h, and patients with insulin-dependent diabetes mellitus (IDDM), withdrawn from insulin and fasted overnight, were given phenylacetate orally and intravenously infused with [3-¹⁴C]lactate and ¹³C-bicarbonate. Rates of hepatic gluconeogenesis relative to Krebs cycle rates were estimated from the ¹⁴C distribution in glutamate from urinary phenylacetylglutamine. Assuming the ¹³C enrichment of breath CO₂ was that of the CO₂ fixed by pyruvate, the enrichment to be expected in blood glucose, if all hepatic glucose production had been by gluconeogenesis, was then estimated. That estimate was compared with the actual enrichment in blood glucose, yielding the fraction of glucose production due to gluconeogenesis. Relative rates were similar in the 60-h fasted healthy subjects and the diabetic patients. Conversion of oxaloacetate to phosphoenolpyruvate was two to eight times Krebs cycle flux and decarboxylation of pyruvate to acetyl-CoA, oxidized in the cycle, was less than one-30th the fixation by pyruvate of CO₂. Thus, in estimating the contribution of a gluconeogenic substrate to glucose production by measuring the incorporation of label from the labelled substrate into glucose, dilution of label at the level of oxaloacetate is relatively small. Pyruvate cycling was as much as one-half the rate of conversion of pyruvate to oxaloacetate. Glucose and glutamate carbons were derived from oxaloacetate formed by similar pathways if not from a common pool. In the 60-h fasted subjects, over 80 % of glucose production was via gluconeogenesis. In the diabetic subjects the percentages averaged about 45 %. [Diabetologia (1995) 38: 831–838] Received: 12 October 1994 and in revised form: 13 January 1995     

Acute insulin response to intravenous glucose,glucagon and arginine in some subjects at risk for Type 1 (insulin-dependent) diabetes mellitus

Summary The relationships between first-phase insulin secretion to i.v. glucagon and i.v. arginine were studied in 19 healthy adult volunteers (Group I) and in 21 subjects at risk for Type 1 (insulin-dependent) diabetes mellitus with either a normal (n=11; Group II a) or a low insulin response to i.v. glucose (n=10; Group II b). Groups I and II a displayed similar insulin responses to the three secretagogues. In contrast, Group II b demonstrated lower insulin responses to both glucagon and arginine than control subjects (p}<0.007 and (p}<0.04 respectively) orthan normo-responders to glucose (#x007D;<0.007 and p<0.04 respectively). In Group II b however, arginine-stimulated insulin release was increased compared to the response to glucose (p}<0.006), while glucagon and glucose led to non-statistically different responses. Five low-responders developed Type 1 diabetes. As a group, they displayed lower responses to glucagon and to arginine than subjects who up to now have not developed the disease (p<0.05 and p<0.0003 respectively). In the subjects who progressed to diabetes, the responses to glucose and glucagon were similarly blunted. In the low-responders who have not developed the disease, no statistical difference could be detected between mean responses to glucagon and glucose, but four out of these five subjects had a glucagon-stimulated response within the control range and higher than their corresponding response to glucose. Arginine led to a higher stimulation than glucose, in subgroups that either progressed to diabetes (p<0.006) or did not (p<0.002). Finally, low-responders who did not develop diabetes displayed similar responses to both glucagon and arginine than normo-responders to glucose. A progressive decrease of arginine-stimulated insulin response may be a later event during pre-Type 1 diabetes than a blunted response to glucose, while a loss of glucagon-stimulated insulin release may be intermediate. Diminished response to all secretagogues may offer better prediction than a low response to glucose alone.     

Fibrinogen and von Willebrand factor in IDDM: relationships to lipid vascular risk factors, blood pressure, glycaemic control and urinary albumin excretion rate: the EURODIAB IDDM complications study

Summary The interrelationships between fibrinogen, von Willebrand factor, a marker of vascular endothelial cell damage, and serum lipids were explored in well-characterised subjects with insulin-dependent diabetes mellitus. The 2091 subjects were enrolled into a cross-sectional, clinic-based study of complications, from 16 European countries: the EURODIAB IDDM Complications study. The anticipated significant relationships between both plasma fibrinogen and plasma von Willebrand factor concentrations and age and glycaemic control, and between fibrinogen and body mass index, were noted. Fibrinogen, adjusted for age and glycated haemoglobin concentration, was also related to smoking habits and was higher in the quartiles with highest systolic and diastolic blood pressures. There was a clustering of vascular risk factors, with a positive relationship between plasma fibrinogen and serum triglyceride concentrations in both genders and between fibrinogen and total cholesterol in males. An inverse relationship between fibrinogen and high density lipoprotein cholesterol was also apparent in males. A prominent feature was a positive relationship between both fibrinogen and von Willebrand factor and albumin excretion rate (p < 0.001 and p < 0.003 respectively) in those with retinopathy but not in those without this complication. In view of previous observations on blood pressure and albuminuria in these subjects the findings are consistent with the hypothesis that microalbuminuria and increased plasma von Willebrand factor are due to endothelial cell perturbation in response to mildly raised blood pressure in subjects with retinopathy. Fibrinogen may also contribute to microvascular disease and its relationships to lipid vascular risk factors suggest a possible pathogenic role in arterial disease in diabetes. [Diabetologia (1997) 40: 698–705] Received: 10 December 1996 and in revised form: 14 March 1997     

Increased arterial stiffness in women,but not in men,with IDDM

Summary For unknown reasons, there is a greater increase in the risk for cardiovascular complications in diabetic women than in diabetic men. Our aim was to study gender-related differences in the mechanical properties of the great arteries in patients with insulin-dependent diabetes mellitus (IDDM) but free from known cardiovascular and cerebrovascular complications. We measured arterial stiffness (, inversely related to arterial compliance) in the abdominal aorta and the common carotid artery non-invasively using echo-tracking sonography in 30 women (mean age 34 years, range 20–61) and 26 men (mean age 38 years, range 22–56) with IDDM. The results were compared with those of healthy individuals of corresponding age and gender. The results showed a marked gender-difference in changes of arterial stiffness. Arterial stiffness was increased in both the abdominal aorta and the common carotid artery in diabetic women compared to control women (p=0.0001 and p=0.0076, respectively). In contrast, there was no significant difference in stiffness of the abdominal aorta or the common carotid artery between the diabetic men and the control men (p=0.69 and p=0.39, respectively). In conclusion, this study has shown that stiffness of the aorta and the common carotid artery is increased in diabetic women but not in diabetic men. Increased arterial stiffness in diabetic women may be a pathogenic factor which could help to explain the gender-related differences in the risk for cardiovascular and cerebrovascular complications in diabetic subjects.Abbreviations IDDM Insulin-dependent diabetes mellitus - arterial stiffness - MAP mean arterial blood pressure - AGE advanced glycation end products     

Defective expression of the apoptosis-inducing CD95 (Fas/APO-1) molecule on T and B cells in IDDM

Summary Triggering of CD95 (Fas/APO-1) cell surface receptors regulates the elimination of autoreactive T and B lymphocytes through a mechanism of cell suicide called apoptosis. Three different mutations involving CD95 or its ligand are responsible for induction of autoimmunity in susceptible mouse strains. To determine whether a defect involving the CD95 receptor is associated with human insulin-dependent diabetes mellitus (IDDM), we have studied the expression of CD95 on peripheral blood mononuclear cells from IDDM patients at different stages of the disease. Three-colour flow cytometry and mean fluorescence analysis showed that T and B lymphocytes from newly diagnosed IDDM and patients with long-standing disease, and subjects at high risk of developing the disease were highly defective in CD95 expression (p<0.001), whereas monocytes from all the groups studied expressed normal amounts of CD95 molecules on their cell surface. T-cell subset analysis showed that the impairment of CD95 expression in IDDM patients and high-risk subjects involved both CD3⁺ CD4⁺ (p<0.001) and CD3⁺ CD8⁺ cells (p range: <0.01–0.001), suggesting that this alteration concerns both helper and cytotoxic T cells. Moreover, after activation in vitro with anti-CD3 monoclonal antibody, T cells from newly diagnosed IDDM patients maintained a reduced CD95 expression during the entire cell culture period (24–72 h) in comparison to the control population (p<0.001). In conclusion, we found a reduced expression of the apoptosis-inducing CD95 receptor on T and B lymphocytes of individuals with clinical and preclinical IDDM. We hypothesize that this defective expression may impair the capacity of autoreactive lymphocytes to undergo CD95-mediated apoptosis, contributing to the lack of control on beta-cell specific B- and T-cell clones.Abbreviations MFI Mean fluorescence intensity - mAb monoclonal antibody - ICA islet cell autoantibody - IAA insulin autoantibody - PE phycoerythrin - FITC fluorescein - Per-CP peridinid chlorophyll protein - PBMC peripheral blood mononuclear cells - AICD activation-induced cell death     

In Finland insulin gene region encoded susceptibility to IDDM exerts maximum effect when there is low HLA-DR associated risk

Summary An association between insulin-dependent diabetes mellitus (IDDM) and polymorphisms of the insulin gene on chromosome 11p15 (INS) is a consistent finding in Europid populations. While one study suggested that the INS association is restricted to HLA-DR4-positive individuals, studies in other Europid populations have shown the disease-associated INS genotype to confer susceptibility independently of HLA-DR. We have investigated the role of INS in susceptibility to IDDM in Finland, which has the highest incidence of diabetes mellitus in the world, at two polymorphic restriction sites, 5 and 3 to the insulin gene. From the DiMe (Childhood Diabetes in Finland) Study we studied 154 diabetic children without regard to HLA-DR type; 108 DR4 positive/non-DR3 diabetic children; 39 DR3 positive/non-DR4 diabetic children; 30 DR4/DR3 positive diabetic children; 31 non-DR4/non-DR3 diabetic children; 96 matched DiMe control subjects and 86 other healthy, non-diabetic Finnish control subjects. We found an overall association between IDDM and INS in the high-risk Finnish population only with the 5 polymorphism and identified an INS haplotype negatively associated with IDDM in Finland. However, among diabetic subjects with a reduced HLA-associated susceptibility (non-DR4/non-DR3) both 3 and 5 INS loci showed an association with IDDM (p values 0.02 and 0.0002, respectively). Thus, in the Finnish population insulin gene-encoded susceptibility to IDDM exerts a maximum effect in those with reduced HLA-associated risk.Abbreviations INS Insulin gene region - VNTR variable number tandem repeats - PCR polymerase chain reaction - RR relative risk - CI confidence intervals - IDDM insulin-dependent diabetes mellitus     

Autoantibodies to oxidised low density lipoproteins in IDDM are inversely related to metabolic control and microvascular complications

Summary Diabetes mellitus is associated with an increased risk of atherosclerosis. The oxidation of low-density lipoproteins (LDL) is considered a key event in the initiation of atherosclerosis. To investigate LDL oxidation in vivo we measured autoantibodies to oxidised LDL (oxLDL) in 94 patients with insulin-dependent diabetes mellitus (IDDM), compared to 27 age-matched, healthy control subjects. Patients and control subjects were screened for autoantibodies using a solid phase ELISA, comparing the binding to oxLDL with that to native LDL (nLDL). In patients with IDDM the oxLDL/nLDL antibody ratio was significantly higher than in control subjects (means ± SEM: 2.24 ± 0.26 vs 1.17 ± 0.17, p < 0.03). Antibody-negative patients had a longer diabetes duration (13.5 ± 1.3 vs 9.1 ± 1.1 years, p < 0.01) and higher actual and mean HbA_{1 c} levels compared to antibody-positive patients (8.8 ± 0.2 vs 7.9 ± 0.2 %, p < 0.005 and 8.3 ± 0.2 vs 7.7 ± 0.2 %, p < 0.03; respectively). In patients with a high microangiopathy score, the antibody ratio was lower than in patients without complications (1.04 ± 0.10 vs 2.40 ± 0.29, p < 0.01). OxLDL specific immune complexes were found exclusively in antibody-negative as compared to antibody-positive patients (18.3 vs 0 %; p < 0.01). Our data demonstrate an inverse relationship between free oxLDL antibodies and the severity of the disease. This apparent paradox can be explained in part by our demonstration of oxLDL immune complexes, masking free antibodies. [Diabetologia (1998) 41: 350–356] Received: 18 June 1997 and in final revised form: 30 September 1997