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Biomedical subjects

K Irsigler

Publications and source records attributed to K Irsigler.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Retrospective analysis of the incidence of severe hypoglycemia in 458 type 1 diabetic patients].

During 1 year a retrospective study concerning frequency and risk markers of severe hypoglycemia was conducted in type-1 diabetic patients undergoing their annual routine check-up. The aim was to contribute to the epidemiology of severe hypoglycemia and to investigate, whether severe hypoglycemia is associated with specific features of therapy (strategy of insulin treatment, level of metabolic control expressed as mean blood glucose and glycosilated hemoglobin, insulin species, use of betablocking agents) or with patient characteristics (age, duration of diabetes, awareness of hypoglycemic symptoms, late complications of diabetes). From the cohort of 710 eligible patients 458 agreed to participate in the study, 61% had experienced severe hypoglycemia at least once, 17% during the last year. The incidence calculated for the whole diabetes duration is 21/100 patient years, and for the last year 56/100 patient years. The following were risk markers for severe hypoglycemia: older age, longer duration of diabetes, reduced awareness of hypoglycemic symptoms, decreasing frequency of symptomatic hypoglycemic episodes, and lower HbA1c. No association was found with the following variables: Serum creatinine, autonomic neuropathy, use of betablocking agents, and presence of anti-insulin antibodies. Intensive insulin therapy with individualized treatment goals in terms of blood glucose control was successful in avoiding severe hypoglycemia in patients who had already experienced them before.

Adolescent↗
PubMed1997

[Follow-up of albumin excretion during pregnancy and post partum in type 1 diabetic patients in comparison with health pregnant probands].

32 diabetic and 31 metabolic healthy pregnant women are studied to answer the following questions: Is there a difference in the albumin-excretion rate (AER) during the pregnancy in primary normoalbuminuric type 1 diabetics and non-diabetics? Is there a difference 6 months post partum between the 2 groups? The average age of the diabetics (D) is 28, of the non-diabetics (ND) 27 years; the diabetics suffer from diabetes mellitus 12.5 years. In the 16th week of pregnancy, we find a AER (D vs. ND) of 5.0 vs. 2.37 micrograms/min (not significant [n.s.]), creatinin in serum 0.77 vs. 0.75 mg/dl (p < 0.05), creatinin clearance 92.5 vs. 103.4 ml/min (n.s.). In the 28th and in the 34th to 38th week, there is no significant elevation of the AER compared to the 16th week; but there is a significant elevation in the diabetics vs. the non-diabetics. 6 months post partum, the AER (D vs. ND) are: 6.13 vs. 5.11 micrograms/min (n.s. vs. 16th week and D vs. ND); in each group one person is found with a positive microalbuminuria (MA): 48.2 micrograms/min (D) and 27.4 mg/min (ND). Another diabetic woman shows post partum an isolated higher value of creatinin in serum: 1.5 mg/dl (without MA). This parameter is post partum significant higher (0.97 [D], 0.96 [ND] mg/dl) than in the 16th week of pregnancy (0.77 [D], 0.75 [ND] mg/dl). The creatinin clearance decreases post partum (pp): 92.2 ml/min (pp) vs. 102.0 ml/min (28th week) in the diabetics (n.s.) and 80.6 ml/min (pp) vs. 111.0 ml/min (28th week) in the non-diabetics (p < 0.05). Concerning the studied renal parameters, there is a significant difference of the albumin-excretion rates during the pregnancy between preconceptional normoalbuminuric type 1 diabetic and non-diabetic women, but 6 months post partum, there is no significant difference. The diabetics show a significant increase of the creatinin in urine and in serum and no significant change of the creatinin clearance 6 months post partum.

Adult↗
PubMed1996

Defective endogenous opioid response to exercise in type I diabetic patients.

Plasma beta-endorphin (beta-E) concentration was determined before, during, and after a standardized incremental exercise test to maximal capacity in eight type I diabetic patients and eight normal control subjects. Diabetic patients were studied under normoglycemic and hyperglycemic conditions in a single-blind random fashion to differentiate between the effects of acute hyperglycemia and of diabetes per se on the beta-E response to exercise. The perceived magnitude of leg effort elicited by exercise was evaluated using a category scale. Whereas plasma beta-E concentrations increased in control subjects with increasing workload, causing significantly higher beta-E levels at the end of exercise than at the beginning (P < .001), no such increase could be observed in the diabetic patients under normoglycemic and hyperglycemic conditions. In addition, baseline plasma beta-E concentrations were significantly lower in normoglycemic (P < .01) and hyperglycemic (P < .001) diabetic patients than in control subjects. Even during the recovery period, patients' beta-E levels remained significantly lower than those of control subjects. At submaximal levels of power output, the perceived intensity of leg effort was significantly higher in normoglycemic and hyperglycemic diabetic patients than in control subjects. We conclude that in type I diabetic patients, the ability of the endogenous opioid system to respond to exercise-induced stress is impaired under hyperglycemic and even under normoglycemic conditions. Considering the effect of endogenous opioids on stress tolerance, such changes may compromise exercise performance in diabetic patients.

Adult↗
PubMed1996

Polymorphism of complement C4 and susceptibility to IDDM and microvascular complications.

OBJECTIVE: The aim of this study was to investigate whether or not the inherited polymorphism of complement C4 is associated with genetic susceptibility to microvascular complications in IDDM as previously reported. RESEARCH DESIGN AND METHODS: We determined C4 phenotypes in 241 patients with IDDM and 140 healthy control subjects by agarose gel electrophoresis and immunoprecipitation. C4 allotype frequencies were compared between patients and healthy control subjects. In addition, we compared allotype frequencies of 83 patients with nephropathy with those of 80 patients without nephropathy and compared those of 50 patients with proliferative retinopathy with those of 68 patients without retinopathy or background retinopathy. Duration of IDDM in control patients was at least 21 years. RESULTS: Patients and healthy control subjects differed at both the C4A (P < 0.00001) and C4B (P < 0.0005) loci. The C4 null allele C4AQ0 was significantly increased in IDDM patients (26.8 vs. 11.8%, P < 0.005). C4B2 was more frequently observed in patients (14.5 vs. 6.8%, P < 0.05) compared with healthy control subjects. No differences were observed in C4 allotype distribution between patients with and without nephropathy or retinopathy. CONCLUSIONS: These data confirm previous reports of an association between the C4 null allele C4AQ0 and IDDM. Our results do not support an association of the inherited polymorphism of complement C4 with genetic susceptibility to microvascular complications in patients with IDDM.

Adolescent↗
PubMed1996

Eicosanoid precursors: potential factors for atherogenesis in diabetic CAPD patients?

Prostaglandins, thromboxanes, and other eicosanoids represent a widespread lipid-mediator system for intercellular signalling, and, hence, have multiple cellular actions. Thus it is not surprising that numerous events in the pathogenesis of atherosclerosis are associated with an altered formation of eicosanoids. To reconsider the availability of eiconsanoid precursors as one possible cause of atherogenesis, the dietary intake and the serum concentrations of arachidonic acid (AA) and eicosapentaenoic acid (EPA) were determined in patients with high risk for atherosclerosis on continuous ambulatory peritoneal dialysis (CAPD) with and without diabetes in comparison to healthy controls and diabetic patients without late complications. The factor AA/EPA in serum was created as a marker for the atherosclerosis risk. The setting was in a CAPD unit in one city hospital. There were 26 CAPD patients [9 with insulin-dependent diabetes mellitus (IDDM), 9 with noninsulin-dependent diabetes mellitus (NIDDM), and 8 without diabetes], 27 IDDM without late complications, and 41 healthy control persons. The AA levels in serum were significantly higher in all of the CAPD groups. In contrast, the EPA concentrations in serum were significantly lower in the CAPD groups, with the lowest EPA levels found in the CAPD-IDDM group. Therefore, the factors AA/EPA in serum were significantly higher in all of the CAPD groups, and again significantly higher in the CAPD-IDDM group than in the other CAPD groups. No differences in the amount of dietary intake of AA existed between the groups. The daily intake of EPA was significantly highest in the control group. Higher concentrations of AA and a lack of n-3 fatty acids lead in the presence of a reduced prostaglandin I2 biosynthesis, to a higher formation rate of potentially proatherogenic metabolites such as thromboxane A2, a vasoconstricting and platelet aggregating agent. Thus, the quotient AA/EPA could possibly be used as a marker of atherogenicity in the future.

Adult↗
PubMed1995

Effect of autonomic neuropathy on ventilatory response to progressive hypercapnia in dialysis patients.

The impact of autonomic neuropathy (common in patients on haemodialysis) on ventilatory response to hypercapnia has been studied. We investigated cardiac reflex tests in 20 patients on chronic haemodialysis (8 patients were found with and 12 without neuropathy of the autonomic nervous system). Using the hyperoxic CO2-rebreathing method (according to Read), we tested the above-mentioned two groups of patients and compared them with 14 healthy control subjects. Accumulation of CO2 in blood with hyperoxic CO2 rebreathing stimulates central chemoreceptors, and therefore causes a progressive rise in minute ventilation. In patients with autonomic neuropathy (n = 8), ventilatory response to increasing pCO2 was significantly lower than that in the controls (1.7 +/- 0.3 versus 3.2 +/- 0.5 l/min/mmHg, P < 0.001). On the other hand ventilatory response in patients without autonomic damage (n = 12) showed no significant difference when compared to controls (3.1 +/- 0.8 l/min/mmHg). There were no differences in lung function, arterial blood gas analysis, blood chemistry, duration on dialysis, and demographic data when comparing the patients with and those without autonomic damage. Our analysis shows different patterns of ventilatory response to increasing pCO2 in patients on haemodialysis. Autonomic neuropathy has to be considered when rebreathing tests are interpreted. The clinical relevance of these findings needs further investigation.

Analysis of Variance↗
PubMed1994

Diaphragmatic function in patients on continuous ambulatory peritoneal dialysis.

We investigated 8 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) for diaphragmatic strength and the neuromechanical efficiency of the diaphragm while the abdomen was filled with dialysate and while it was empty. Maximum transdiaphragmatic pressure (Pdimax) served as parameter for diaphragmatic strength; diaphragmatic efficiency was assessed by simultaneously monitoring transdiaphragmatic pressure (Pdi) and diaphragmatic electromyogram (EMGdi) during room-air breathing and hyperoxic CO2-rebreathing. After instilling dialysate, Pdimax increased from 76.7 +/- 12.1 cmH2O to 92.2 +/- 16.3 cmH2O (P < 0.05). While the slopes of the regression lines relating minute ventilation (VE) to arterial CO2 tension, and the change in VE for a given change in Pdi during hypercapnic rebreathing were similar in both states, the slope of EMGdi vs Pdi was significantly steeper when the abdomen was filled (P < 0.05). The increase in Pdimax observed in the filled state may suggest an adaptive rightward shift in the diaphragm's force-length relationship in CAPD patients, although this mechanism is insufficient to prevent a reduction of neuromechanical efficiency of the diaphragm.

Adult↗
PubMed1994

High-dose intravenous melphalan in a patient with multiple myeloma and oliguric renal failure.

A kappa light-chain myeloma was diagnosed as the underlying disease in a 52-year-old woman with acute oliguric renal failure. The patient was erroneously treated with high-dose intravenous melphalan (60 mg/m2). Because of this overdose treatment with granulocyte colony-stimulating factor was initiated, but pronounced absolute leukopenia (white blood cell count < 0.5 x 10(9)/l) developed and lasted for 13 days. Following melphalan treatment a continuous increase in urine volume was accompanied by a decrease of serum creatinine and blood urea nitrogen. Within 10 days after the administration of melphalan the patient no longer required hemodialysis. We conclude that high-dose chemotherapy in combination with hematopoietic growth factors should be considered in individual cases with newly diagnosed light-chain nephropathy.

Acute Kidney Injury↗
PubMed1994

[Prevalence of cardiac autonomic neuropathies in uremia and diabetes mellitus].

In the absence of relevant data, the prevalence of cardiac autonomic neuropathy was investigated in patients with diabetes mellitus or uremia due to other causes and diabetic patients with endstage renal failure. 117 patients (40 on a dialysis program without diabetes, 32 with diabetes mellitus type 1 but no nephropathy, 16 type 1 and 13 type 2 diabetic uremic patients, 16 diabetic patients with a kidney graft) and 25 healthy control subjects underwent assessment of the cardiorespiratory reflexes. The evaluation of parasympathetic damage was of particular interest. Definite parasympathetic dysfunction was detected in 32% of the non-diabetic uremic and in 19% of the non-uremic type 1 diabetic patients. Furthermore, 88% of type 1 and 77% of type 2 diabetic patients on dialysis and 75% of diabetic patients after kidney transplantation had evidence of autonomic neuropathy.

Adult↗
PubMed1994

[Detection of an insulinoma in pregnancy--a rare cause of hypoglycemia].

An insulinoma was diagnosed in a 26 year-old woman who suddenly went into hypoglycemic coma in the 38th week of an apparently uncomplicated pregnancy. On review of the history it became apparent that symptoms due to hypoglycemia had been present since the 16th week of pregnancy. Continuous intravenous infusion of glucose was administered and the patient was delivered of a healthy child 5 days later. Investigations revealed 2 insulinoma nodules in the tail of the pancreas which were successfully removed 2 weeks post partum.

Adult↗
PubMed1994

[Insulin-dependent diabetes mellitus:"EURODIAB IDDM Complications Study"--results from the Vienna center].

The EURODIAB IDDM complications study is a multicenter clinical study for evaluation of the prevalence of microvascular, macrovascular and acute metabolic complications in randomly selected samples of insulin-dependent diabetic patients attending 31 European diabetes centers. A total of 3250 patients were studied (mean age: 32.7 +/- 10 years, mean duration of diabetes: 14.7 +/- 9.3 years) by standardized, validated methods. The third medical department of the Vienna-Lainz hospital participated from Austria. 122 patients, age: 34.9 +/- 9.9 years, duration of diabetes: 16 +/- 10 years were recruited from this center. There was a wide variation in the frequency of complications between the different European centres: Prevalence of diabetic retinopathy 25-60%; Vienna showed the lowest prevalence (25%). Metabolic control (HbA1c) ranged from 5.7-9.4%; Vienna shared the second place with two other centers (6.0%). Despite the very low HbA1c in the Viennese population, the frequency of severe hypoglycemic attacks was in the lower range, which is an extraordinary result in this study. Incipient diabetic renal disease, characterized by microalbuminuria varied in frequency between 15 and 33% (Vienna 23%). Important associations of raised blood pressure (frequency in all centers: 8-41%, Vienna: 29%) with renal disease and retinopathy have implications for the initiation of preventive measures. The data on diabetic complications obtained from the EURODIAB study permit a comparison between the different European centers and emphasize the need for implementation of the St. Vincent recommendations.

Adolescent↗
PubMed1993

Endogenous opioid system during inspiratory loading in patients with type I diabetes.

To investigate the activity of the endogenous opioid system in patients with insulin-dependent diabetes mellitus during ventilatory stress situations, we measured plasma beta-endorphin levels in six male and five female diabetic patients breathing against fatiguing inspiratory resistive loads. The patients had to generate with each inspiration an esophageal pressure (Pes) 80% of maximum until they were exhausted and could no longer develop target Pes. The loaded breathing run was repeated three times with a 1-min interval between each run. Duty cycle, tidal volume, and breathing frequency were constant in all tasks. For each run plasma beta-endorphin levels were measured, inspiratory effort sensation assessed using a modified Borg scale, and inspiratory muscle endurance evaluated by the length of time the task could be maintained (Tlim). A group of 11 sex-, age-, height-, and weight-matched healthy individuals served as control subjects. Tlim was significantly lower in the diabetic patients. Evaluating respiratory effort during the three test runs in control subjects at a time corresponding to the break point of loaded breathing in patients showed significantly lower Borg ratings in the control group than in the patient group. Baseline plasma beta-endorphin was significantly lower in the diabetic patients (10.6 +/- 2.1 versus 27.0 +/- 4.2 pg/ml, p < 0.01). Additionally, whereas resistive loaded breathing caused a further increase in plasma beta-endorphin concentration in the control group (p < 0.005), absolutely no increase was found in the diabetic patients. We conclude that the endogenous opioid system in insulin-dependent diabetic patients does not respond to stress caused by breathing against fatiguing inspiratory resistive loads.

Adult↗
PubMed1993

No effect of naloxone on ventilatory response to progressive hypercapnia in IDDM patients.

The ventilatory response to hyperoxic progressive hypercapnia was examined by comparing 3 test groups: 7 diabetic patients with AN, 8 diabetic patients without AN, and 8 normal control subjects. In each group, a significant linear correlation was found between PaCO2 and VE. The slopes of the regression curves relating PaCO2 to VE were significantly steeper in the healthy control subjects and diabetic patients without AN than in those with AN (P < 0.01). We conclude that the ventilatory response to progressive hypercapnia is reduced in diabetic patients with AN. By analyzing the power spectrum and the amplitude behavior of the diaphragmatic EMG (calculated from the fc and RMS, respectively), we could exclude a disturbance of neural descending pathways and respiratory muscle dysfunction as possible causal mechanisms for the impaired ventilatory response to increasing CO2. By using lung function analysis, causal factors such as alterations in respiratory system mechanics also could be excluded. As diabetes is known to affect the endogenous opioid system, which, in turn, affects the ventilatory response to CO2, naloxone, as a specific opioid antagonist, was administered in all 3 test groups. Naloxone produced a significant increase of ventilatory response to hypercapnia in the healthy control subjects (P < 0.01), but produced no effect in either of the diabetic groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Morbidity and mortality in type 1 and type 2 diabetes mellitus after the diagnosis of diabetic retinopathy].

One to ten years after laser coagulation for diabetic retinopathy, 229 type I diabetics (mean age 44.3 years) and 157 type II diabetics (mean age 65 years) were re-studied for morbidity and mortality (progression of late damage, duration of survival, cause of death). The duration of diabetes at the first laser coagulation averaged 23.1 years for type I diabetics (15.9 years for type II). Average period from the first laser coagulation to the re-examination was 6.5 years for type I, 5.1 for type II diabetics. Of those patients still alive 6.7% had gone blind (type II: 7.3%). 2.1% and 4.6%, respectively, were receiving dialysis treatment, while renal transplantation had been performed in 3.1 and 1.8%, respectively. Stroke was the most frequent macrovascular complications (8.4 and 16.5%), followed by leg amputation (3.6 and 14.7%) and myocardial infarction (3.7 and 18.3%). 83 patients had died: 35 (15.3%) type I and 48 (30.6%) type II diabetics. Causes of death were septicaemia 14.3% (0%), uraemia 11.4% (8.3%), myocardial infarction 14.3% (33.3%), heart failure 8.6% (29.2%) and stroke 5.7% (6.3%). 10.7% (24.2%) had died within the first 5 years after laser coagulation. Despite a lower incidence of blindness in patients with diabetic retinopathy, the vascular disease progresses in other vascular regions so that a large proportion of diabetics will develop renal failure or die early from macrovascular complications.

Adult↗
PubMed1992

Mechanical load on the inspiratory muscles during exercise hyperpnea in patients with type 1 (insulin-dependent) diabetes mellitus.

The aim of this study was to evaluate the difference between Type 1 (insulin-dependent) diabetic patients and healthy control subjects regarding inspiratory muscle load during exercise hypernea. For this purpose an incremental progressive exercise test on a cycle ergometer was performed by 36 Type 1 diabetic patients and 40 healthy subjects. In order to determine the mechanical load on the inspiratory muscles breath by breath, we selected the following two parameters, which represent the pressure generated by the inspiratory muscles as well as the duration and velocity of their contraction: (1) the oesophageal tension time index, which is the product of the duty cycle (ratio of inspiratory time to total breath cycle duration) and the mean oesophageal pressure expressed as a percentage of the maximal oesophageal pressure and (2) the mean oesophageal pressure change per time unit during the inspiratory phase of each breathing manoeuver, which is expressed as a fraction of the subject's maximal oesophageal pressure. Comparison of the two groups revealed that at similar levels of ventilation the mechanical load on the inspiratory muscles was significantly higher in the Type 1 diabetic patients than in the control subjects. When the loading was stopped the maximal ventilation was lower in the patients. Nevertheless, they reported a degree of respiratory effort sensation comparable to the control group, which seems to have been caused by an increase of the mechanical load on the ventilatory muscles.

Adult↗
PubMed1992

Pulmonary gas exchange and oxygen uptake during exercise in patients with type 1 diabetes mellitus.

In order to investigate pulmonary gas exchange and cardiopulmonary performance in Type 1 diabetes, 36 patients underwent a progressive incremental exercise test on a cycle ergometer. Cardiopulmonary variables were measured, and arterial blood gases determined on samples obtained from an indwelling catheter in the radial artery. The results were compared with those from 40 control subjects. In the patients, the maximum power (Wmax) and maximum oxygen uptake (VO2max) were lower than in the control subjects (Wmax 186 +/- 52 (+/- SD) vs 233 +/- 48 W, p less than 0.05; VO2max 2.56 +/- 0.71 vs 3.17 + 0.77 l min-1, p less than 0.05). At comparable levels of power output, however, no significant abnormality was observed in the difference between alveolar and arterial oxygen pressure (P(A-a)O2), and the ratio of physiological dead space to tidal volume (VD/VT ratio). These data indicate that in Type 1 diabetic patients, despite their reduced maximum oxygen uptake, gas transfer during exercise is not limited and thus does not contribute to the impairment of exercise capacity.

Adult↗