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L Heinemann

Publications and source records attributed to L Heinemann.

At least 37 records · Page 2Linked to original sources

Rapid and long-acting analogues as an approach to improve insulin therapy: an evidence-based medicine assessment.

This review summarizes the results of clinical trials with the currently available insulin analogues (i.e., insulin lispro, insulin aspart, and insulin glargine) and evaluates their clinical benefit applying the standards of evidence-based medicine. All analogues show a more physiological time-action profile with either a shorter onset and shorter duration of action (insulin lispro and insulin aspart) or a more constant effect lasting at least 24 hours (insulin glargine). These advantages in the time-action profiles have been shown to improve various surrogate parameters (e.g., postprandial blood glucose concentrations) in a number of randomized controlled trials. Only a few studies are available, however, demonstrating a benefit on patient-oriented clinical endpoints as decrease in glycated hemoglobin (HbA(1c)), reduction of hypoglycemic episodes, and improvement in quality-of-life. This review focuses on the impact of the use of insulin analogues on these endpoints. Provided that insulin therapy is optimized as a whole (rather than just switching from human insulin to insulin analogues) all 3 analogues show (modest) beneficial impact on these endpoints. Finally, we review the relevant data concerning the safety aspects of the various analogues, thus allowing the reader to perform an individual risk-benefit-assessment.

Animals↗

Alternative routes of administration as an approach to improve insulin therapy: update on dermal, oral, nasal and pulmonary insulin delivery.

For the past 75 years subcutaneous injections have been the only route of delivery of insulin therapy to diabetic patients. During this time, numerous attempts have been made to explore alternative routes for systemic insulin administration. However, thus far, no feasible other way of non-invasive insulin delivery has been developed. Dermal insulin application does not result in a reproducible and sufficient transfer of insulin across the highly efficient skin barrier. The dream of an "insulin tablet" has also not become a reality, the main problem being digestion and a lack of a specific peptide carrier system in the gut. Nasal insulin application was considered for a number of years as a potential method, because of the rapid absorption of insulin across the nasal mucosa. However, relative bioavailability was low and required use of absorption enhancers and more importantly, the metabolic effect lasted too short to be of clinical usefulness. To date the most promising alternative route of insulin administration, is the pulmonary delivery of insulin by inhalation which will likely lead to a practically usable system within the next few years. For maximal rate of absorption insulin must be applied deep into the lung, i.e., into the alveoli. A considerable number of inhalers (in combination with appropriate insulin formulations), which are ask to generate insulin particles with an appropriate size for pulmonary delivery, are currently in the clinical phase of development. The pharmaco dynamic effects of insulin formulations administered via the lung are comparable to, or even faster than, those of s.c. injected regular insulin or rapid-acting insulin analogues. The relative biopotency of inhaled insulin in most cases is approximately 10%, i.e., the dose of insulin administered must be 10-fold higher than with s.c. application. The published results of clinical trials thus far, indicate that metabolic control is comparable to that of s.c. insulin therapy. As of to date no serious side effects have been reported from these human trials. In summary, it appear that after several decades of research, for the first time a feasible alternative route for insulin administration is within reach.

Administration, Cutaneous↗

Impact of diabetic nephropathy on pharmacodynamic and Pharmacokinetic properties of insulin in type 1 diabetic patients.

OBJECTIVE: To quantify pharmacokinetic and pharmacodynamic properties of regular insulin and insulin lispro in type 1 diabetic patients with and without overt diabetic nephropathy. RESEARCH DESIGN AND METHODS: In this double-blind, two-way cross-over, euglycemic (5 mmol/l) glucose clamp study, we investigated the metabolic response to subcutaneous injections of regular insulin and insulin lispro (0.2 U/kg) in 12 type 1 diabetic patients with overt diabetic nephropathy (proteinuria >500 mg/24 h and/or serum creatinine >1.5 mg/dl; NP group) and in a control group of 12 type 1 diabetic patients with normal renal function (DC group). RESULTS: Peak plasma free insulin levels with insulin lispro (359 [NP] vs. 254 pmol/l [DC]) were higher and time to maximal insulin concentrations (85 [NP] vs. 99 min [DC]) shorter than with regular insulin (213 [NP] vs. 144 pmol/l [DC]; 118 [NP] vs. 153 min [DC]) in both patient groups. Overall insulin levels for regular insulin and for insulin lispro were higher in patients with overt diabetic nephropathy compared with control patients. Time to maximal metabolic effect was shorter with insulin lispro than with regular insulin in both patient groups (102 vs. 191 min [NP]; 105 vs. 172 min [DC]). The overall metabolic effect of regular insulin but not of insulin lispro was lower in patients with diabetic nephropathy than in diabetic control patients (967 vs. 1,510 mg/kg, respectively). CONCLUSIONS: Although insulin levels are higher in patients with overt diabetic nephropathy, the metabolic response to regular insulin is reduced. Insulin lispro maintains its characteristic pharmacokinetic and pharmacodynamic properties in patients with overt diabetic nephropathy.

Adult↗

Noninvasive glucose measurement by monitoring of scattering coefficient during oral glucose tolerance tests. Non-Invasive Task Force.

BACKGROUND: Continuous glucose monitoring by means of optical glucose sensors would allow patients with diabetes to check their metabolic control to their convenience. In an earlier study, we showed that noninvasive glucose monitoring is feasible for rapid changes in blood glucose by means of measuring the scattering coefficient of human skin. In this study, we investigated whether also slower changes in blood glucose, this time induced by an oral glucose load, can also be monitored by this approach. METHODS: Five healthy subjects and 13 patients with type 2 diabetes have been given a 75-g oral glucose load. Portable noninvasive systems were used to measure the skin tissue scattering coefficient. For this purpose, two optical sensor heads were attached directly to the skin of each volunteer. Light was applied to the skin and the reflected light intensity was registered. RESULTS: In 8 of 10 measurements, correlation of changes in scattering coefficient with changes in glycemia was acceptable. In 19 of 26 measurements (73%) of patients with type 2 diabetes the observed changes in the scattering coefficient also correlated in acceptable manner. The accordance between the simultaneous measurements of the two sensor heads was acceptable in 13 of 18 volunteers and patients studied. There were virtually no differences in the quality of the measurements between healthy volunteers and patients with diabetes. CONCLUSIONS: This study shows that also slow changes in blood glucose induced by an oral glucose load can be monitored by registration of scattering coefficient changes. It remains to be elucidated why this has not been possible in all experiments.

Adult↗

Recurrent use of newer oral contraceptives and the risk of venous thromboembolism.

The epidemiological studies that assessed the risk of venous thromboembolism (VTE) associated with newer oral contraceptives (OC) did not distinguish between patterns of OC use, namely first-time users, repeaters and switchers. Data from a Transnational case-control study were used to assess the risk of VTE for the latter patterns of use, while accounting for duration of use. Over the period 1993-1996, 551 cases of VTE were identified in Germany and the UK along with 2066 controls. Totals of 128 cases and 650 controls were analysed for repeat use and 135 cases and 622 controls for switching patterns. The adjusted rate ratio of VTE for repeat users of third generation OC was 0.6 (95% CI:0.3-1.2) relative to repeat users of second generation pills, whereas it was 1.3 (95% CI:0.7-2.4) for switchers from second to third generation pills relative to switchers from third to second generation pills. We conclude that second and third generation agents are associated with equivalent risks of VTE when the same agent is used repeatedly after interruption periods or when users are switched between the two generations of pills. These analyses suggest that the higher risk observed for the newer OC in other studies may be the result of inadequate comparisons of pill users with different patterns of pill use.

Adult↗

A cross-over evaluation of different methods and devices to measure blood pressure in type 1 diabetic patients with nephropathy.

BACKGROUND: In type 1 diabetic patients with nephropathy, tight blood pressure control has been shown to prevent the progression of the disease. Up until now, self-monitoring, ambulatory and office blood pressure values have not been compared in these patients. Thus, we have evaluated blood pressure values obtained in the office by a physician and at home by self-monitoring with those measured under ambulatory conditions in these patients. Additionally, for blood pressure self-monitoring, three different devices (the sphygmomanometer, upper-arm oscillometer and wrist oscillometer) were compared. METHODS: Twenty-one treated hypertensive type 1 diabetic patients [age 45+/-9 years, duration of diabetes 33+/-12 years (mean+/-SD)] with overt diabetic nephropathy participated in this study. At both baseline and the end of the study, daytime ambulatory blood pressure measurement was performed. Office blood pressure was measured at baseline. Additionally, all the patients measured their blood pressure over a 3-week period using each of the three different devices, in random order, for 1 week. RESULTS: The mean office blood pressure values (135+/-21/85+/-12mmHg) were higher than both the ambulatory (131+/-23/80+/-12, P<0.05) and self-monitoring values (130+/-14/78+/-10; P<0.05 for systolic and P<0.02 for diastolic values). The difference between the ambulatory and self-monitoring values were not statistically significant. Diastolic blood pressure values measured with the oscillometric wrist device showed a trend towards higher values when compared to those measured with the sphygmomanometer and with the oscillometric upper-arm device (P=0.065 for diastolic values). CONCLUSION: Office blood pressure measurements may over-estimate blood pressure in patients with type 1 diabetes and diabetic nephropathy. Because the oscillometric wrist device tends to over-estimate diastolic values, upper-arm devices should be preferred for blood pressure self-monitoring in these patients.

Arm↗

Time-action profile of the long-acting insulin analog insulin glargine (HOE901) in comparison with those of NPH insulin and placebo.

OBJECTIVE: To study the pharmacodynamic properties of the subcutaneously injected long-acting insulin analog HOE901 (30 microg/ml zinc) in comparison with those of NPH insulin and placebo. RESEARCH DESIGN AND METHODS: In this single-center double-blind euglycemic glucose clamp study, 15 healthy male volunteers (aged 27 +/- 4 years, BMI 22.2 +/- 1.8 kg/m2) received single subcutaneous injections of 0.4 U/kg body wt of HOE901, NPH insulin, or placebo on 3 study days in a randomized order. The necessary glucose infusion rates (GIRs) to keep blood glucose concentrations constant at 5.0 mmol/l were determined over a 30-h period after administration. RESULTS: The injection of HOE901 did not induce the pronounced peak in metabolic activity observed with NPH insulin (GIRmax 5.3 +/- 1.1 vs. 7.7 +/- 1.3 mg x kg(-1) x min(-1)) (P < 0.05); after an initial rise, metabolic activity was rather constant over the study period. This lack of peak was confirmed by a lower glucose consumption in the first 4 h after injection (area under the curve from 0 to 4 h [AUC(0-4 h)] 1.02 +/- 0.34 vs. 1.48 +/- 0.34 g/kg) (P < 0.001) with HOE901, as compared with NPH insulin. In this single-dose study, the metabolic effect measured over a period of 30 h was lower with HOE901 than with NPH insulin (AUC(0-30 h) 7.93 +/- 1.82 vs. 9.24 +/- 1.29 g/kg) (P < 0.05). CONCLUSIONS: This study shows that the soluble long-acting insulin analog HOE901 induces a smoother metabolic effect than NPH insulin, from which a better substitution of basal insulin requirements may follow.

Adult↗

Intra-individual variability of the metabolic effect of inhaled insulin together with an absorption enhancer.

OBJECTIVE: To study the metabolic effect and the variability of the effect elicited by inhalation of 87.2 U insulin powder combined with an absorption enhancer. The metabolic effect was compared with that of 10.2 U regular insulin injected subcutaneously and of 5.5 U regular insulin given intravenously RESEARCH DESIGN AND METHODS: In this single-center open euglycemic glucose clamp study 13 healthy male volunteers received 5 insulin administrations on separate study days: once as an intravenous dose, once as a subcutaneous injection, and 3 times by inhalation, in randomized order. Glucose infusion rates (GIRs) necessary to keep blood glucose concentrations constant at 5.0 mmol/l were determined over an 8-h period after administration. RESULTS: After inhalation of the insulin powder aerosol, the onset of action was substantially more rapid than after subcutaneous insulin injection, and maximal action was reached earlier (86+/-47 vs. 182+/-53 min, P<0.0001). The maximal glucose infusion rate after inhalation of insulin was comparable to that after subcutaneous insulin injection (9.2+/-2.6 vs. 8.8+/-2.8 mg x kg(-1) x min(-1), NS). The metabolic effect in the first 2 h after inhalation was significantly greater than that after subcutaneous insulin injection (amount of glucose infused: 0.88+/-0.25 vs. 0.59+/-0.20 g x kg(-1) x 120 min(-1), P<0.0001). However, the total metabolic effect after inhalation and subcutaneous injection was comparable (2.50+/-0.76 vs. 2.56+/-0.69 g x kg(-1) x 480 min(-1), NS). The relative bioefficacy of inhaled insulin calculated in relation to the data from the subcutaneous insulin application was 12.0+/-3.5% (absolute bioefficacy 10.1+/-3.1%) but was highest in the first 2 h after application (18.5+/-3.7%; absolute bioefficacy 8.2+/-4.1%). The intraindividual variability of the metabolic response induced by insulin inhalation was 14+/-9% for the maximal glucose infusion rate, 15+/-10% for the time-to-maximal effect, and 16+/-12% for the total amount of glucose infused. CONCLUSIONS: This feasibility study shows that inhaled insulin with an absorption enhancer has a pronounced metabolic effect compared with the results of a previous study of inhaled insulin without an enhancer. The intraindividual variability of the metabolic effect was comparable with that of inhaled and subcutaneously injected insulin.

Administration, Inhalation↗

Injection-meal interval: recommendations of diabetologists and how patients handle it.

Because regular insulin does not lower blood glucose immediately after injection many physicians recommend an injection-meal interval (IMI). By asking patients to inject well before beginning a meal, these physicians hope to compensate for the lag time between the injection of insulin and its onset of action. The aim of our study was to find out what physicians recommend to their patients with respect to the IMI, when prescribing intensive insulin therapy. A total of 58 diabetologists were surveyed by means of a structured questionnaire. A fixed IMI of 15 (0-30) min [median (range)] was recommended by 29% of the 58 diabetologists, and a flexible IMI was recommended by 71%. The minimal interval for the suggested flexible IMI was 0 min and the maximal interval 45 min (median 23 min). We compared these results with findings of 192 patients with Type 1 diabetes from a population based study. In this study patients were asked by questionnaire about their daily life handling of the IMI. Among the group of 134 patients reporting use of a flexible IMI, 62% used an IMI of < or = 15 min, 16% one of 20-25 min, and 21% one of > or = 30 min. There were 12 patients using a flexible IMI who adapted it so frequently that they could not state a typical interval. A total of 58 patients (30%) used a fixed IMI (67% used an IMI of < or = 15 min, 7% one of 20-25 min, 26% one of > or = 30 min). Our surveys show that diabetologists advocating intensive insulin therapy usually recommend an IMI shorter than 30 min. The majority of patients (75%) with Type 1 diabetes use an IMI of < 30 min in daily life.

Adult↗

Time-action profile of the soluble, fatty acid acylated, long-acting insulin analogue NN304.

AIMS: To compare the pharmacokinetic and pharmacodynamic properties of subcutaneously injected NN304, a novel long-acting insulin analogue, to NPH-insulin during euglycaemic glucose clamps in 11 healthy volunteers. METHODS: On three study days NN304 was injected in three different doses (0.15, 0.3, 0.6 U/kg body weight), while NPH-insulin (0.3 U/kg) was injected in identical dose on two other days. RESULTS: Injection of NN304 resulted in a linear and proportional increase in total NN304 concentrations (AUC0-1440 min: 0.15 U/kg: 344+/-43, 0.3 U/kg: 666+/-82, 0.6 U/kg: 1295+/-210 nmol/l; P<0.001). Maximal concentrations (609+/-140, 1046+/-283, 2033+/-460 pmol/l; P<0.001) were reached after 4-6 h. The metabolic response (expressed as maximal glucose infusion rates (GIR)) induced by subcutaneous injection of NN304 did not show the pronounced peak seen with NPH-insulin in an identical dose: GIRmax 3.2+/-1.1 vs. 4.4+/-1.8 mg/kg/min (P<0.05 for 0.3 U/kg NN304 vs. NPH-insulin; mean of both study days with NPH-insulin, all others not significant). NN304 also showed a slower onset of action, as indicated by a significantly higher tmax (446+/-162 vs. 359+/-175 min) and lower AUC0-240min (0.5+/-0.3 vs. 0.8+/-0.4 g/kg/240min; P<0.05, respectively). The three different doses of NN304 induced a significantly different glucose consumption in the first 720 min after injection (AUC0-720 min 1.1+/-0.6, 1.9+/-0.8, 1.7+/-0.8 g/kg; P<0.05 for 0.15 U/kg), but not over the whole study period (AUC0-1440 min 1.8+/-1.1, 3.1+/-1.3, 2.8+/-1.4 g/kg). CONCLUSIONS: Injection of NN304 at different doses resulted in an increase in total NN304 concentration in a linear dose-response effect and a more even metabolic effect than NPH-insulin. However, we found no clear dose-response in its metabolic effect.

Acylation↗

Measurement of insulin sensitivity: influence of potassium supply during euglycaemic glucose clamps in healthy volunteers.

Insulin sensitivity can be quantitatively measured by the hyperinsulinaemic euglycaemic glucose clamp technique. Infusion of insulin during the clamp procedure leads to a decline of kalaemia unless potassium is supplied. We investigated whether supplementation of potassium during euglycaemic glucose clamps influences insulin sensitivity. In a randomised study the insulin sensitivity index (S(I)) was determined with two-step hyperinsulinaemic (insulin infusion rates 0.25 (step 1) and 1.0 mU kg(-1) min(-1) (step 2)) euglycaemic (5.0 mmol L(-1)) glucose clamps in 20 healthy male volunteers on two different study days. On one day blood potassium was kept constant by means of a variable i.v. potassium chloride infusion ("eukalaemic potassium clamp"), whereas on the other day the decline in blood potassium was monitored only. Without potassium supply kalaemia decreased from basal levels of 4.35 +/- 0.18 mval L(-1) to 4.25 +/- 0.17 (step 1) and further to 3.88 +/-0.14 mval L(-1) (step 2 (mean +/- SD)). Without and with potassium supply the insulin sensitivity index measured was comparable (S1 10.6 +/- 3.6 vs. 9.5 +/- 3.5 ml min(-1) m2 per microU ml(-1), n.s.; glucose infusion rates 3.6+/-1.6/12.6 +/- 2.6 (step 1/step 2) vs. 3.7 +/- 1.5/12.2 +/- 2.7 mg kg(-1) min(-1), n.s.). In conclusion, this study shows that potassium supply during hyperinsulinaemic euglycaemic glucose clamps in healthy subjects does not influence the insulin sensitivity index.

Adult↗

Lack of effects of the beta3-adrenoreceptor agonist UL-TG 307 on insulin sensitivity and insulin secretion in Type 2 diabetic patients.

The effects of a novel beta3-adrenoreceptor agonist, UL-TG 307, on insulin sensitivity and insulin secretion, lipid metabolism, and body weight were investigated. Thirteen diet treated male Type 2 diabetic patients participated in a randomized, double-blind, placebo controlled cross-over trial with two 14 day administration periods with placebo and UL-TG 307 (24 mg daily). After each administration period insulin secretion was assessed by means of an OGTT and insulin sensitivity was measured by an hyperinsulinaemic euglycaemic glucose clamp. Lipid metabolism was evaluated by measuring non-esterified fatty acid, glycerol, and triglyceride serum concentrations at the end of each administration period. Treatment with UL-TG 307 did not improve insulin sensitivity (insulin sensitivity index (S(I)): UL-TG 307 2.5 -/+ 0.6 (mean +/- SD) vs. placebo 2.2 +/- 0.8 ml/min*m2 per microU/ml) nor increased insulin secretion (area under the serum insulin profile AUC0-240/plasma glucose AUC0-240: UL-TG 307 8.8 +/- 7.4 vs. placebo 8.3 +/- 6.4 microU/ ml/mmol/l). No differences in lipid metabolism, metabolic control, and body weight were observed. We conclude that two weeks' administration of the beta3-adrenoreceptor agonist UL-TG 307 in a daily dose of 24 mg did not lead to any significant effect in diet treated type 2 diabetic patients.

Adrenergic beta-Agonists↗

Insulin sensitivity in patients with essential hypertension: no influence of the ACE inhibitor enalapril.

We studied the effect of an ACE inhibitor (Enalapril [ENA], 10 mg o.d.) and a calcium-channel blocker (Nitrendipine [NIT], 20 mg o.d.) on insulin sensitivity in a double-blind cross-over study. Insulin sensitivity was measured by a two-step hyperinsulinemic euglycemic clamp. Serum potassium concentrations were kept constant during the clamp procedure by means of a variable potassium infusion. Twenty patients with essential hypertension (age 35+/-12 years [mean+/-SD], BMI 31.9+/-5.0 kg m2, initial blood pressure 152+/-10/99+/-6 mmHg) were treated with ENA or NIT for 4 weeks, respectively, with a wash-out period of 3 weeks. No carry-over effects or period effects were observed. Both drugs induced a comparable decline in systolic and diastolic blood pressure (ENA - 15+/-9/ - 13+/-8 mmHg, NIT -16+/-8/- 12+/-6 mmHg). No significant change in body weight occurred with both treatments (ENA -0.4+/-2.0; NIT 0.6+/-1.1 kg). Neither drug had a significant impact on any parameter of insulin sensitivity measured (e.g. insulin sensitivity index SI: ENA 5.2+/-2.0 [basal 5.1+/-2.2], NIT 5.8+/-3.0 [basal SI 5.1+/-2.4) mi/min x m2/microU/ml). In conclusion, no significant differences between ENA and NIT on insulin sensitivity were observed. The reduction of blood pressure had no apparent effect on insulin sensitivity.

Adult↗

Influence of continuous combined estradiol-norethisterone acetate preparations on insulin sensitivity in postmenopausal nondiabetic women.

OBJECTIVE: Estrogen-progestogen replacement therapy (HRT) may be associated with deterioration of insulin sensitivity in comparison to estrogens alone, which tend to improve insulin sensitivity in postmenopausal women. Insulin sensitivity with the use of continuous combined 17-beta estradiol/norethisterone acetate (E2/NETA) preparations has not been examined before in postmenopausal women. DESIGN: In a double-blind randomized parallel study, we evaluated the effect of 2 mg E2/1 mg NETA (high dose E2/NETA), 1 mg E2/0.5 mg NETA (low dose E2/NETA), or placebo (P) on the insulin sensitivity index (SI) in three groups (18 women/group) of postmenopausal nondiabetic women (follicle stimulating hormone [FSH] > 40 mIU/mL, mean +/- SD) aged 56 +/- 3 years, BMI 25 +/- 4 kg/m2, cholesterol 233 +/- 42 mg/dL, and triglycerides 87 +/- 36 mg/dL. Insulin sensitivity was measured by means of a two-step hyperinsulinemic euglycemic glucose clamp (insulin infusion rate, 0.25 and 1.0 mU/kg/min for 120 min each) at baseline and after 3 months of daily administration of high dose E2/NETA, low dose E2/NETA, or P. Analysis was performed assuming equivalence of start-end changes of insulin sensitivity among treatment groups (Anderson-Hauck test). RESULTS: SI was 7.7 +/- 2.9, 7.5 +/- 3.4, 6.8 +/- 2.2 at baseline and 6.3 +/- 3.0, 7.9 +/- 2.5, 7.1 +/- 3.1 mL/min/m2 per mu U/mL 3 months after the administration of high dose E2/NETA, low dose E2/NETA, and P, respectively. The low dose E2/NETA group had start-to-end changes of SI which were equivalent to the P group (0.4 [95% confidence interval [CI] -0.8; 1.7] vs. 0.4 [-0.3; 1.0]) (p = 0.02). For the high dose E2/NETA group, equivalence could not be shown with either the P (p = 0.89) or with the low dose E2/NETA group (p = 0.90). SI within the high dose E2/NETA group decreased by -1.5 (95% CI -2.7; -0.2) mL/min/m2 per mu U/mL. HbAlc decreased from 5.3 +/- 0.3 to 5.1 +/- 0.3% within the high dose E2/NETA group (p < 0.03) and remained unchanged within the low dose E2/NETA and P group. Fasting plasma glucose, fasting serum insulin, and C-peptide, as well as triglycerides and BMI were comparable among the groups at baseline and after 3 months. Total cholesterol decreased by 12% and 8% in women treated with high dose and low dose E2/NETA (p < 0.02), respectively, and remained unchanged within the P group. CONCLUSIONS: These results indicate that 3 months use of a low dose continuous E2/NETA preparation does not change insulin sensitivity in postmenopausal women. At high dose of E2/NETA, a modest decrease seems possible. The effects of E2/NETA on other parameters of carbohydrate and lipid metabolism are neutral or favorable.

Aged↗

The blood glucose lowering effects of exercise and glibenclamide in patients with type 2 diabetes mellitus.

Physical exercise is associated with a fall in serum insulin levels, whereas sulphonylurea administration increases insulin release. To date, the opposing effects of exercise and sulphonylurea administration have not been systematically studied in Type 2 diabetic patients, who are not infrequently treated with sulphonylureas. In this study nine patients with Type 2 diabetes mellitus were subjected to four treatments in random order on separate days: (A) endurance exercise after the administration of 3.5 mg glibenclamide; (B) as A but given only 1.75 mg glibenclamide; (C) as A but with placebo; (D) rest and administration of 1.75 mg glibenclamide. Exercise and placebo resulted in only a small decrease in glycaemia. Rest and administration of 1.75 mg glibenclamide led to a moderate but steady fall in blood glucose concentrations. If glibenclamide administration and exercise were combined, blood glucose concentrations declined more markedly. Serum insulin concentrations showed a physiological decrease during exercise and placebo administration. If patients rested after administration of glibenclamide serum insulin levels rose and remained elevated. When exercise and glibenclamide were combined the rise in serum insulin levels was blunted and insulin levels fell once exercise was begun. Thus, exercise attenuates the glibenclamide induced increase in serum insulin in moderately hyperglycaemic Type 2 diabetic patients. Nevertheless, exercise has a substantial hypoglycaemic effect in glibenclamide treated Type 2 diabetic patients.

Adult↗