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Biomedical subjects

David R Owens

Publications and source records attributed to David R Owens.

17 recordsLinked to original sources

The systemic inflammatory response to exercise in adults with cystic fibrosis.

Exercise is associated with release of inflammatory mediators in the circulation and there is evidence that the exercising muscles and tendons are sources of interleukin-6. Due to the catabolic effects of some cytokines, increased release in circulation might contribute to alterations in body composition in adults with cystic fibrosis. We hypothesised that exercise of moderate intensity would generate increased blood concentrations of some inflammatory mediators. We investigated the change in blood concentrations of interleukin-6, tumour necrosis factor alpha and their soluble receptors after a structured exercise (box stepping) of intensity similar to that encountered during activities of daily living in 12 adults with cystic fibrosis and mean (95% confidence interval) FEV1 55.6 (44.4, 66.8)% predicted, body mass index 23.0 (21.3, 24.6) kg/m2 and 12 healthy subjects. The increments post-exercise for all inflammatory mediators and lactate corrected for the work performed until voluntary exhaustion were greater for patients, while the total work was less for patients (all p<0.01). Daytime variability of the inflammatory mediators was assessed in eight patients and was less than the change due to exercise. We report greater increments in circulating concentrations of some cytokines with moderate exercise in adults with cystic fibrosis compared to healthy subjects.

Adult↗

Postprandial glucose regulation: new data and new implications.

BACKGROUND: Type 2 diabetes is characterized by a gradual decline in insulin secretion in response to nutrient loads; hence, it is primarily a disorder of postprandial glucose (PPG) regulation. However, physicians continue to rely on fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c) to guide management. OBJECTIVES: The objectives of this article are to review current data on postprandial hyperglycemia and to assess whether, and how, management of type 2 diabetes should change to reflect new clinical findings. METHODS: Articles were selected from MEDLINE searches (key words: postprandial glucose, postprandial hyperglycemia, and cardiovascular disease) and from our personal reference files, with emphasis on the contribution of postprandial hyperglycemia to overall glycemic load or cardiovascular (CV) risk. RESULTS: About 33% of people diagnosed as having type 2 diabetes based on postprandial hyperglycemia have normal FPG. PPG contributes > or =70% to the total glycemic load in patients who are fairly well controlled (HbA1c <7.3%). Furthermore, there is a linear relationship between the risk of CV death and the 2-hour oral glucose tolerance test (OGTT). Increased mortality is evident at OGTT levels of approximately 90 mg/dL (5 mmol/L), which is well below current definitions of type 2 diabetes. Biphasic insulin aspart was shown to be more effective at reducing HbA1c below currently recommended levels than basal insulin glargine (66% vs 40%; P < 0.001), and it reduced endothelial dysfunction more effectively than regular insulin (P < 0.01). Repaglinide achieved regression of carotid atherosclerosis (intima-media thickness) in 52% of patients versus 18% for glyburide (P < 0.01) over 1 year, although levels of HbA1c and CV risk factors were similar for both treatment groups. Finally, acarbose reduced the relative risk of CV events by 49% over 3.3 years versus placebo in patients with impaired glucose tolerance (2.2% vs 4.7%; P = 0.03) and by 35% over > or =1 year in patients with type 2 diabetes (9.4% vs 6.1%; P = 0.006). CONCLUSIONS: All components of the glucose triad (ie, FPG, HbA1c, and PPG) should be considered in the management of type 2 diabetes. Therapy targeted at PPG has been shown to improve glucose control and to reduce the progression of atherosclerosis and CV events; therefore, physicians should consider monitoring and targeting PPG, as well as HbA1c and FPG, in patients with type 2 diabetes.

Atherosclerosis↗

Silent substitution S-cone electroretinogram in subjects with diabetes mellitus.

A defect in the blue sensitive mechanism has been reported in certain ocular and systemic diseases. For example, tritanopic colour vision defects and changes to the S-cone electroretinogram (ERG) have been demonstrated in glaucoma and diabetes mellitus. Electrophysiological methods of eliciting the S-cone ERG, however, often result in considerable L- and M-cone intrusion. We report the findings of a study employing the silent substitution S-cone ERG technique, which is thought to represent an almost pure S-cone signal, and the L'Anthony desaturated D15 colour vision test in subjects with Type 1 or 2 diabetes mellitus with no or minimal background retinopathy. The results of this study show a significantly increased S-cone ERG b-wave implicit time and significantly worse colour vision in those with background retinopathy compared with those with no diabetic retinopathy. This suggests that S-cone pathway dysfunction may be responsible for the deterioration in colour vision found in diabetes mellitus.

Adolescent↗

Effects of exercise on the absorption of insulin glargine in patients with type 1 diabetes.

OBJECTIVE: To study the effects of exercise on the absorption of the basal long-acting insulin analog insulin glargine (Lantus), administered subcutaneously in individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS: A total of 13 patients (12 men, 1 woman) with type 1 diabetes on a basal-bolus insulin regimen were studied. (125)I-labeled insulin glargine at the usual basal insulin dose was injected subcutaneously into the thigh on the evening (2100) before the study day on two occasions 1 week apart. Patients were randomly assigned to 30 min intense exercise (65% peak oxygen uptake [Vo(2peak)]) on one of these visits. The decay of radioactive insulin glargine was compared on the two occasions using a thallium-activated Nal gamma counter. Blood samples were collected at regular intervals on the study days to assess plasma glucose and insulin profiles. RESULTS: No significant difference was found in the (125)I-labeled insulin glargine decay rate on the two occasions (exercise vs. no exercise; repeated-measures ANOVA, P = 0.548). As expected, a significant fall in plasma glucose was observed over the exercise period (area under curve above fasting [DeltaAUC] glucose: -0.39 +/- 0.11 vs. -1.30 +/- 0.16 mmol . l(-1) . h(-1); nonexercise vs. exercise; P = 0.001), but insulin levels did not differ significantly on the two occasions (DeltaAUC insulin: -2.1 +/- 3.9 vs. 1.5 +/- 6.2 pmol . l(-1) . h(-1); nonexercise versus exercise; P = 0.507). CONCLUSIONS: An intense 30-min period of exercise does not increase the absorption rate of the subcutaneously injected basal long-acting insulin analog insulin glargine in patients with type 1 diabetes.

Absorption↗

Beta-cell response during a meal test: a comparative study of incremental doses of repaglinide in type 2 diabetic patients.

OBJECTIVE: To assess the effects of incremental doses of repaglinide on postprandial insulin and glucose profiles after a standard 500-kcal test meal. RESEARCH DESIGN AND METHODS: Sixteen diet-treated Caucasians with type 2 diabetes (mean HbA(1c) 8.4%) were enrolled in this randomized, open-label, crossover trial. Subjects received 0.5, 1, 2, and 4 mg repaglinide or placebo in a random fashion, followed by a standard 500-kcal test meal on 5 separate study days, 1 week apart. RESULTS: The insulinogenic index (DeltaI30/DeltaG30) and insulin area under the curve (AUC) from 0 to 30 min (AUC(0-30)) were higher with the 4-mg drug dose compared with the two lower doses and with 2 mg compared with 0.5 mg. On subgroup analysis, the incremental insulin responses were apparent only in the fasting plasma glucose (FPG) < 9-mmol/l subgroup of subjects and not in the FPG >9-mmol/l subgroup. There was a significant dose-related increase in the late postprandial insulin secretion (insulin AUC(120-240)), which resulted in hypoglycemia in four subjects. Proinsulin-to-insulin ratios at 30 and 60 min improved with increasing doses of repaglinide; higher drug doses (2 and 4 mg) were more effective than the 0.5- and 1-mg doses. CONCLUSIONS: Significant dose-related increases in early insulin secretion were found only in less advanced diabetic subjects. In advanced diabetic patients, only the maximum dose (4 mg) was significant compared with placebo. Better proinsulin-to-insulin processing was noted with increasing drug doses.

Adult↗

Anemia and diabetes in the absence of nephropathy.

OBJECTIVE: Patients with diabetes commonly have a greater degree of anemia for their level of renal impairment than those presenting with other causes of renal failure. To clarify the contribution and differing roles of diabetes and nephropathy in the development of anemia in diabetic patients, we examined the hematologic and hematinic parameters of diabetic patients without nephropathy. RESEARCH DESIGN AND METHODS: The study group was comprised of 62 patients with type 2 diabetes who had been followed for a median of 7 years. For the study, these patients had additional samples taken during their annual routine blood testing for the measurement of extra parameters, including serum ferritin, serum erythropoietin (Epo) levels, and the percentage of reticulocytes. These measurements were combined with the routine parameters Hb, hematocrit, HbA(1c), and glomerular filtration rate. RESULTS: In all, 8 of the 45 male patients (17.8%) and 2 of the 17 female patients (11.8%) were classified as anemic (Hb <13g/dl and <11.5g/dl, respectively). Although only a small number of the patients had anemia as defined by normal values, a retrospective analysis of individual patients over time revealed a sustained though small decrease in Hb from initial presentation. A statistically significant difference in Epo levels (P = 0.016 by Kruskal-Wallis test) was observed from the group with the lowest (Hb < or =11.5) to that with the highest (Hb > or =14.5) Hb values, with a median Epo value of 37 (interquartile range 24-42) vs. 13 (9-15) IU/l, respectively. In contrast, there was no evidence of an increased reticulocyte response to higher levels of Epo (r = 0.134 [Pearsons], P = 0.36). Reticulocyte counts ranged from 44 (38-57) to 76.5 (56-83) in the lowest and highest Hb groups, respectively. CONCLUSIONS: Although only a small number of subjects in the group were overtly anemic, all subjects had an ongoing, small but significant decrease in Hb since presentation. This study of diabetic patients without nephropathy shows an expected increase in Epo production in response to lowering levels of Hb but without the expected reticulocyte response.

Adult↗

The effect of post prandial glucose changes on oscillatory potentials in subjects with type 2 diabetes mellitus.

PURPOSE: To investigate the effect of elevated plasma glucose levels on oscillatory potentials (OPs) in patients with diabetes mellitus. METHOD: 15 patients with type 2 diabetes mellitus, with no ophthalmoscopically visible signs of diabetic retinopathy (NDR), were recruited, mean (SD) age 65.1 (10.91) years and duration 5.95 (4.95) years. Plasma glucose levels and OPs were recorded before, during and after a meal tolerance test (MTT), at times 0, 90 and 210 min. OPs were recorded following 5 min adaptation to a blue mesopic background (1.17 cd m(-2)), and elicited using a white 5 ms stimulus flickering at 5 Hz frequency over the blue background. RESULTS: Plasma glucose increased significantly from 0 to 90 min during the MTT. This corresponded with an increase in mean amplitude of OP1-4, and a significant increase in the summed amplitudes. Summed OP amplitudes were 14.52 microv and 18.38 microv at time 0 and 90 min respectively. Between times 90 and 210 min plasma glucose levels decreased significantly back to baseline. OP1 and OP2 amplitudes increased slightly and OP3 and OP4 amplitudes decreased markedly, resulting in a non-significant reduction of the summed amplitudes. No significant changes in latencies were seen. CONCLUSIONS: Summed OP amplitudes, which are known to reflect the efficiency of the retinal circulation, increased with elevated plasma glucose. This effect was not immediately reversible. Latencies appear not to be affected.

Adult↗

Population and individual minimal modeling of the frequently sampled insulin-modified intravenous glucose tolerance test.

Population approaches are more robust estimators of insulin sensitivity (SI) and glucose effectiveness (SG) with the minimal model of glucose kinetics during an intravenous glucose tolerance test (IVGTT). We assessed the performance of 3 population methods, iterative two-stage (ITS), Bayesian hierarchical Markov chain Monte Carlo (MCMC), and NONMEM first-order conditional estimation (FOCE) with interaction (NM), and made a comparison with the standard two-stage method (STS) employing the weighted nonlinear regression analysis. To evaluate accuracy of individual and population estimates, 40 simulated insulin-modified frequently sampled IVGTTs (IM-FSIVGTT) were derived from real IM-FSIVGTTs (0.3 g glucose per kg body weight with 0.02 U/kg insulin at 20 minutes; 30 samples over 180 minutes) performed in 40 healthy Caucasian subjects (male/female, 22/18; age, 46 +/- 9 years; body mass index [BMI], 26.7 +/- 5.7 kg. m(-2); mean +/- SD). The population methods assumed a log-normal population distribution of parameters. All methods gave a similar but overestimated population SG by 9% to 13%. Population SI was underestimated to a different degree by the methods (STS 6%, ITS 10%, MCMC 13%, and NM 7%). The between-subject variability of SG was overestimated by STS and underestimated by the population methods (true 33%, STS 40%, ITS 19%, MCMC 24%, NM 24%; coefficient of variation). For SI, this quantity was well estimated by all methods (true 79%, STS 80%, ITS 82%, MCMC 83%, NM 82%). The results for individual estimates indicate that STS performs better than the population methods when estimating SI (STS 12%, ITS 16%, MCMC 16%, NM 16%; 1 outlying subject excluded; root mean squared error expressed as percent of mean) but worse for SG (STS 28%, ITS 21%, MCMC 20%, NM 19%). We conclude that the robust performance of population approaches, preventing parameter estimation failures associated with the nonlinear regression analysis, is not required with IM-FSIVGTT in subjects with normal glucose tolerance. The standard two-stage technique is the preferred method under such circumstances.

Adult↗

Bayesian hierarchical approach to estimate insulin sensitivity by minimal model.

We adopted Bayesian analysis in combination with hierarchical (population) modelling to estimate simultaneously population and individual insulin sensitivity (SI) and glucose effectiveness (SG) with the minimal model of glucose kinetics using data collected during insulin-modified intravenous glucose tolerance test (IVGTT) and made comparison with the standard non-linear regression analysis. After fasting overnight, subjects with newly presenting Type II diabetes according to World Health Organization criteria (n =65; 53 males, 12 females; age, 54 +/- 9 years; body mass index, 30.4 +/- 5.2 kg/m2; means+/-S.D.) underwent IVGTT consisting of a 0.3 g of glucose bolus/kg of body weight given at time zero for 2 min, followed by 0.05 unit of insulin/kg of body weight at 20 min. Bayesian inference was carried out using vague prior distributions and log-normal distributions to guarantee non-negativity and, thus, physiological plausibility of model parameters and associated credible intervals. Bayesian analysis gave estimates of SI in all subjects. Non-linear regression analysis failed in four cases, where Bayesian analysis-derived SI was located in the lower quartile and was estimated with lower precision. The population means of SI and SG provided by Bayesian analysis and non-linear regression were identical, but the interquartile range given by Bayesian analysis was tighter by approx. 20% for SI and by approx. 15% for SG. Individual insulin sensitivities estimated by the two methods were highly correlated ( rS=0.98; P <0.001). However, the correlation in the lower 20% centile of the insulin-sensitivity range was significantly lower than the correlation in the upper 80% centile ( rS=0.71 compared with rS=0.99; P <0.001). We conclude that the Bayesian hierarchical analysis is an appealing method to estimate SI and SG, as it avoids parameter estimation failures, and should be considered when investigating insulin-resistant subjects.

Adult↗

Automated detection of fundus photographic red lesions in diabetic retinopathy.

PURPOSE: To compare a fundus image-analysis algorithm for automated detection of hemorrhages and microaneurysms with visual detection of retinopathy in patients with diabetes. METHODS: Four hundred fundus photographs (35-mm color transparencies) were obtained in 200 eyes of 100 patients with diabetes who were randomly selected from the Welsh Community Diabetic Retinopathy Study. A gold standard reference was defined by classifying each patient as having or not having diabetic retinopathy based on overall visual grading of the digitized transparencies. A single-lesion visual grading was made independently, comprising meticulous outlining of all single lesions in all photographs and used to develop the automated red lesion detection system. A comparison of visual and automated single-lesion detection in replicating the overall visual grading was then performed. RESULTS: Automated red lesion detection demonstrated a specificity of 71.4% and a resulting sensitivity of 96.7% in detecting diabetic retinopathy when applied at a tentative threshold setting for use in diabetic retinopathy screening. The accuracy of 79% could be raised to 85% by adjustment of a single user-supplied parameter determining the balance between the screening priorities, for which a considerable range of options was demonstrated by the receiver-operating characteristic (area under the curve 90.3%). The agreement of automated lesion detection with overall visual grading (0.659) was comparable to the mean agreement of six ophthalmologists (0.648). CONCLUSIONS: Detection of diabetic retinopathy by automated detection of single fundus lesions can be achieved with a performance comparable to that of experienced ophthalmologists. The results warrant further investigation of automated fundus image analysis as a tool for diabetic retinopathy screening.

Algorithms↗

Identification and management of diabetic nephropathy in the diabetes clinic.

OBJECTIVE: To examine the prevalence and management of diabetic nephropathy in a diabetes clinic. RESEARCH DESIGN AND METHODS: Characteristics of nephropaths identified by existing screening practice (phase I, albuminuria >20 mg/l in three separate urine samples), were compared with those identified by a nurse-led management program (phase II, in which screening for nephropathy was based on albumin-to-creatinine ratio in a single random urine specimen). RESULTS: In phase I, 644 patients attended a diabetes clinic over a 6-month period. Microalbuminuria results were available for 485 patients (75%). A total of 115 patients were identified as nephropaths (prevalence 17.8%). Of these patients, 91% had type 2 diabetes. During phase II, prospective analysis of urinary albumin-to-creatinine ratio was carried out in 880 patients over 8 months. A total of 174 patients were identified as nephropaths (prevalence 20%). Of these, 134 patients had been identified by existing screening protocols. Forty had no previous record of microalbuminuria and were therefore newly identified by prospective screening. Systolic blood pressure guidelines were met in only 31% of all known nephropaths and 26.5% of newly diagnosed nephropaths. Diastolic blood pressure guidelines were met in 36% of all known and 38% of newly diagnosed nephropaths. In the patient group of known nephropaths from phases I and II, 62% were prescribed ACE inhibitors (ACEIs) or angiotensin II receptor (AIIR) antagonists. In the newly identified nephropathy patient cohort from phase II, 48% used ACEIs or AIIR antagonists. CONCLUSIONS: Introduction of a nurse-led management program significantly improved detection of nephropathy. We are currently evaluating its impact on clinical management.

Aged↗

Pulmonary function, body composition, and protein catabolism in adults with cystic fibrosis.

Increased survival in cystic fibrosis (CF) is associated with bone thinning and fat-free mass (FFM) loss. We hypothesized that the severity of lung disease would be associated with increased protein catabolism and systemic inflammatory status in clinically stable patients. Forty adults with CF and 22 age-matched healthy subjects were studied. Body composition was determined by dual-energy X-ray absorptiometry. Urinary pseudouridine (PSU), a marker of protein breakdown, and cross-linked N-telopeptides of type I collagen (NTx), a marker of bone connective tissue breakdown, serum tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and their soluble receptors were measured. A 3-d food intake diary revealed 21 patients had a low energy intake. Excretion of PSU (p = 0.019) and NTx (p < 0.01) was increased in patients and was inversely related to FEV(1); PSU (r = - 0.53, p = 0.001) and NTx (r = - 0.43, p < 0.01). Increased excretion of PSU and NTx (p < 0.05 for both) was also related to a low FFM. All inflammatory mediators were greater in patients and were related to PSU and NTx. Clinically stable adults were catabolic with both cellular and connective tissue protein breakdown, which was related to lung disease severity, systemic inflammation, and body composition.

Adult↗

Insulin sensitivity in type 2 diabetes: univariate and multivariate techniques to derive estimates of insulin sensitivity from the insulin modified intravenous glucose tolerance test (FSIGT).

The use of univariate and multivariate techniques to derive estimates of insulin sensitivity from the insulin modified FSIGT were investigated in 12 Type 2 diabetic subjects aged (mean+/-S.D.) 59+/-9.5 years and BMI 28.1+/-2.2 kg m(-2), who underwent both a FSIGT and an isoglycemic hyperinsulinemic clamp. Reproducibility of the FSIGT was tested in four patients on three separate occasions. FSIGT data were assessed by both univariate and multivariate techniques. The sensitivity index for the FSIGT ranged from 0.162 to 3.292 (mean 1.378) x 10(-4) x l min(-1) mU(-1) for the univariate approach and from 0.163 to 2.727 (mean 1.378) x 10(-4) x l min(-1) mU(-1) for the multivariate method. Mean S(Iclamp) was 44.41 x 10(-4) x l(-2) min(-1) x mU(-1) (range 22.0-77.92). The correlation of the insulin sensitivity indices between the clamp and the FSIGT was 0.51 (P=0.056) for the univariate and 0.67 (P=0.017) for the multivariate analyses. Repeated FSIGTs showed a lower variability for the multivariate than for the standard approach.

Aged↗

New horizons--alternative routes for insulin therapy.

Since the introduction of insulin therapy 80 years ago, the lives of millions of patients with diabetes have been saved, prolonged and immeasurably improved. However, restoring normal glucose levels in diabetic patients through administering insulin by subcutaneous injection has proved virtually impossible. The consequences for patients are serious complications, including diabetic retinopathy and nephropathy, which tend to result from persistent hyperglycaemia. Maximizing glucose control in diabetic patients requires several daily injections. In an effort to reduce this burden, alternative and less-intrusive routes for the administration of insulin are being explored.

Administration, Cutaneous↗

Associations of glucose control with insulin sensitivity and pancreatic beta-cell responsiveness in newly presenting type 2 diabetes.

We examined the ability of indices of insulin sensitivity and pancreatic beta-cell responsiveness to explain interindividual variability of clinical measures of glucose control in newly presenting type 2 diabetes. Subjects with newly presenting type 2 diabetes (n = 65; 53 males and 12 females; age, 54 +/- 1 yr; body mass index, 30.5 +/- 0.7 kg/m(2); mean +/- SE) underwent an insulin-modified iv glucose tolerance test to determine minimal model-derived insulin sensitivity (S(I)), glucose effectiveness, first-phase insulin secretion, and disposition index. Subjects also underwent a standard meal tolerance test (MTT) to measure fasting/basal (M(0)) and postprandial (M(I)) pancreatic beta-cell responsiveness. Stepwise linear regression used these indices to explain interindividual variability of fasting and postprandial plasma glucose and insulin concentrations and glycated hemoglobin (HbA(1C)). All measures of pancreatic beta-cell responsiveness (M(0), M(I), and first-phase insulin secretion) were negatively correlated with fasting plasma glucose (P < 0.01) and positively correlated with fasting plasma insulin (FPI) and insulin responses to MTT (P < 0.05). S(I) demonstrated negative correlation with FPI (P < 0.001) but failed to correlate with any glucose variable. M(I) followed by disposition index (composite index of insulin sensitivity and pancreatic beta-cell responsiveness) were most informative in explaining interindividual variability. It was possible to explain 70-80% interindividual variability of fasting plasma glucose, FPI, HbA(1C), and insulin responses to MTT, and only 25-40% interindividual variability of postprandial glucose. In conclusion, postprandial insulin deficiency is the most powerful explanatory factor of deteriorating glucose control in newly presenting type 2 diabetes. Indices of insulin sensitivity and pancreatic beta-cell responsiveness explain fasting glucose and HbA(1C) well but fail to explain postprandial glucose.

Blood Glucose↗

Comparison of the effects of three insulinotropic drugs on plasma insulin levels after a standard meal.

OBJECTIVE: To compare the effects of repaglinide, glipizide, and glibenclamide on insulin secretion and postprandial glucose after a single standard 500-kcal test meal. RESEARCH DESIGN AND METHODS: A total of 12 type 2 diabetic patients with early diabetes (mean HbA(1c) of 6.1%) and 12 matched control subjects were enrolled in this randomized, double-blind, crossover trial. Subjects received placebo, 2 mg repaglinide, 5 mg glipizide, and 5 mg glibenclamide in a random fashion during the trial. Administration of each drug was followed by a single standard 500-kcal test meal. A washout period of 7-12 days existed between the four study visits. RESULTS: All three drugs were equally effective on the total prandial insulin secretion (area under the curve [AUC] -15 to 240 min). However, clear differences were noted in the early insulin secretion (AUC -15 to 30 min); both repaglinide and glipizide increased secretion in nondiabetic subjects by approximately 61 and 34%, respectively, compared with placebo. In the diabetic patients, the difference versus placebo was 37 and 47%, respectively. The difference between glipizide and glibenclamide reached significance in both groups of subjects, whereas repaglinide was more effective than glibenclamide only in the healthy nondiabetic subject group. All three drugs were effective in decreasing total glucose AUC in the nondiabetic and diabetic population. In the nondiabetic subjects, however, repaglinide was significantly more effective than glibenclamide. The differences disappeared in the diabetic subjects, probably as a result of increased prevalence of insulin resistance in this group. CONCLUSIONS: Repaglinide and glipizide but not glibenclamide significantly enhanced the early insulin secretion in both nondiabetic and diabetic subjects with preserved beta-cell function after a single standard meal.

Aged↗