Search

Objective: We previously showed that exenatide (EXE) enhanced insulin secretion after 1 year of treatment, relative to insulin glargine (GLAR), with a similar glucose-lowering action. These effects were not sustained after a 4-week off-drug period. This article reports the results after additional 2 years of exposure.Research Design and Methods: Sixty-nine metformin-treated patients with type 2 diabetes were randomized to EXE or GLAR. Forty-six patients entered the 2-year extension study in which they continued their allocated therapy. Thirty-six completed (EXE: n = 16; GLAR: n = 20) the 3-year exposure period. Insulin sensitivity (M value) and β-cell function were measured by euglycemic hyperinsulinemic clamp followed by hyperglycemic clamp with arginine stimulation at pretreatment (week 52) and 4 weeks after discontinuation of study medication (week 56 and week 172). First-phase glucose stimulated C-peptide secretion was adjusted for M value and calculated as the disposition index (DI).Results: At 3 years, EXE and GLAR resulted in similar levels of glycemic control: 6.6 ± 0.2% and 6.9 ± 0.2%, respectively (P = 0.186). EXE compared with GLAR significantly reduced body weight (-7.9 ± 1.8 kg; P < 0.001). After the 4-week off-drug period, EXE increased the M value by 39% (P = 0.006) while GLAR had no effect (P = 0.647). Following the 4-week off-drug period, the DI, compared with pretreatment, increased with EXE, but decreased with GLAR (1.43 ± 0.78 and -0.99 ± 0.65, respectively; P = 0.028).Conclusions: EXE and GLAR sustained HbA(1c) over the 3-year treatment period, while EXE reduced body weight and GLAR increased body weight. Following the 3-year treatment with EXE, the DI was sustained after a 4-week off-drug period. These findings suggest a beneficial effect on β-cell health. [ABSTRACT FROM AUTHOR]

Objective: Traditional blood glucose-lowering agents do not sustain adequate glycemic control in most type 2 diabetic patients. Preclinical studies with exenatide have suggested sustained improvements in beta-cell function. We investigated the effects of 52 weeks of treatment with exenatide or insulin glargine followed by an off-drug period on hyperglycemic clamp-derived measures of beta-cell function, glycemic control, and body weight.Research Design and Methods: Sixty-nine metformin-treated patients with type 2 diabetes were randomly assigned to exenatide (n = 36) or insulin glargine (n = 33). beta-Cell function was measured during an arginine-stimulated hyperglycemic clamp at week 0, at week 52, and after a 4-week off-drug period. Additional end points included effects on glycemic control, body weight, and safety.Results: Treatment-induced change in combined glucose- and arginine-stimulated C-peptide secretion was 2.46-fold (95% CI 2.09-2.90, P < 0.0001) greater after a 52-week exenatide treatment compared with insulin glargine treatment. Both exenatide and insulin glargine reduced A1C similarly: -0.8 +/- 0.1 and -0.7 +/- 0.2%, respectively (P = 0.55). Exenatide reduced body weight compared with insulin glargine (difference -4.6 kg, P < 0.0001). beta-Cell function measures returned to pretreatment values in both groups after a 4-week off-drug period. A1C and body weight rose to pretreatment values 12 weeks after discontinuation of either exenatide or insulin glargine therapy.Conclusions: Exenatide significantly improves beta-cell function during 1 year of treatment compared with titrated insulin glargine. After cessation of both exenatide and insulin glargine therapy, beta-cell function and glycemic control returned to pretreatment values, suggesting that ongoing treatment is necessary to maintain the beneficial effects of either therapy. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Insulin is often postponed for years because initiation is time-consuming. We sought to compare initiation of insulin individually and in groups with respect to change in A1C and several other parameters in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: A randomized (1:1), multicenter, two-arm, parallel design study with a recruiting period of up to 14 weeks and a 24-week treatment period. Either in groups of 4-8 or individually, using the same personnel and education program, 121 insulin-naive type 2 diabetic patients with an A1C of 7.0-12.0% were randomized to initiate bedtime insulin glargine. The patients visited the treatment center before and at the time of insulin initiation and at 6, 12, and 24 weeks. Patients self-adjusted the insulin dose to achieve a fasting plasma glucose 4.0-5.5 mmol/l. RESULTS: At 24 weeks, mean +/- SE A1C had decreased from 8.7 +/- 0.2 to 6.9 +/- 0.1% in those treated individually and from 8.8 +/- 0.2 to 6.8 +/- 0.1% in those in groups (not significant [NS]). Insulin doses averaged 62 +/- 5 IU and 56 +/- 5 IU at 24 weeks (NS), respectively. The frequency of hypoglycemia was similar. The total time (visits and phone calls) spent in initiating insulin in the patients in groups (2.2 +/- 0.1 h) was 48% less than in those treated individually (4.2 +/- 0.2 h). Diabetes treatment satisfaction improved significantly in both sets of patients. CONCLUSIONS: Similar glycemic control and treatment satisfaction can be achieved by initiating insulin in groups and individually. Starting insulin in groups takes one-half as much time as individual initiation. [ABSTRACT FROM AUTHOR]

Objective: To examine whether and how improvement of glycemic control by long-term insulin therapy decreases endothelial activation as measured by serum levels of the soluble adhesion molecules sE-selectin and vascular cell adhesion molecule (VCAM-1) and whether the drug used to lower blood glucose in addition to insulin influences such a response.Research Design and Methods: Circulating adhesion molecules were measured before and after 3 and 12 months of therapy in 81 patients with type 2 diabetes and 41 subjects without diabetes. The patients were treated with bedtime administration of NPH insulin combined with either glibenclamide (n = 19), metformin (n = 17), glibenclamide and metformin (n = 17), or morning administration of NPH insulin (n = 23).Results: Before insulin therapy, serum sE-selectin level was 71% higher in the patients with type 2 diabetes (77 +/- 4 ng/ml) than in the normal subjects (45 +/- 3 ng/ml, P < 0.001), whereas levels of sVCAM-1 were comparable (420 +/- 25 vs. 400 +/- 11 ng/ml, respectively). Glycemic control in all patients improved as judged from a decrease in HbA1c from 9.7 +/- 0.2 to 7.6 +/- 0.1% (P < 0.001). sE-selectin decreased to 67 +/- 4 ng/ml by 3 months (P < 0.001 vs. 0 months) and then remained unchanged until 12 months (70 +/- 4 ng/ml P < 0.001 vs 0 months). sVCnM-1 levels at 12 months was similar to those at 0 months (416 +/- 25 ng/ml). The change in glycemic control, measured by HbA1c, but not in other parameters, was correlated with the change of sE-selectin (r = 0.41, P < 0.001) within the patients with type 2 diabetes. The decreases in sE-selectin were not different between the various treatment groups.Conclusions: We conclude that improvement in glycemic control by administration of insulin alone or insulin combined with either glibenclamide, metformin, or both agents induces a sustained decrease in sE-selectin, the magnitude of which seems to be dependent on the degree of improvement in glycemia. These data suggest that sE-selectin might provide a marker of effects of treatment of chronic hyperglycemia on endothelial activation. [ABSTRACT FROM AUTHOR]

Objective: Frequency domain analysis of heart rate variability (HRV) is used to assess cardiovascular autonomic function. There are no prospective data on the sensitivity of its various components to glycemia or other diabetes-related risk factors compared with conventional tests and with other complications of diabetes.Research Design and Methods: In 1985, possible risk factors of future complications were determined in 115 children with type 1 diabetes. In 1996, the presence of complications (HRV analysis, conventional tests of autonomic function, urinary albumin excretion rate [UAER], and retinopathy) were assessed in 83 of these patients (age 32 +/- 1 years, duration of diabetes 22 +/- 1 years).Results: Poor glycemic control (measured as lifetime glycemic exposure or HbA1c in 1985) was the most important independent predictor of decreases in all measures of absolute power of HRV (total power [TP] and very low frequency, low frequency [LF], and high frequency [HF] power) and square root of the mean square of R-R interval differences but not of changes of normalized measures or ratios (normalized HF and LF LF/HF). Other significant independent predictors of autonomic dysfunction were late age of onset of diabetes, female sex, and high BMI. To examine the sensitivity of the various tests to glycemia, the patients were divided into tertiles based on lifetime glycemic exposure (A1c months). Glycemic exposure in the tertiles averaged 194 +/- 25 A1c months (20 years of HbA1c 0.8% above normal), 556 +/- 19 A1c months(20 years of HbA1c 2.3% above normal), and 963 +/- 30 A1c months (20 years of HbA1c 4% above normal). Tests of complications that were significantly abnormal in patients already in the lowest tertile and were correlated with glycemia were TP and severity of retinopathy. Of conventional tests, only the ratio of length of R-R intervals during expiration to inspiration (E/I ratio) was significantly related to glycemic exposure, but it required high glycemic exposure (20 years of HbA1c 4% above normal) to be abnormal. UAER was significantly increased only in the highest tertile of glycemic exposure.Conclusions: TP and retinopathy score were much more sensitive to antecedent glycemia than conventional tests of autonomic function or UAER and were significantly abnormal in patients exposed to approximately 20 years' duration of an HbA1c 0.8% above normal. [ABSTRACT FROM AUTHOR]

Objective: Available basal insulin formulations do not provide a constant and reliable 24-h insulin supply. We compared the efficacy and safety of glargine (a long-acting insulin analog) and NPH insulins in insulin-naive type 2 diabetic patients treated with oral antidiabetic agents.Research Design and Methods: There were 426 type 2 diabetic patients (age 59 +/- 9 years, BMI 28.9 +/- 4.3 kg/m2, mean +/- SD) with poor glycemic control on oral antidiabetic agents randomized to treatment for 1 year with bedtime insulin glargine or bedtime NPH insulin. Oral agents were continued unchanged. The fasting blood glucose (FBG) target was 6.7 mmol/l (120 mg/dl).Results: Average glycemic control improved similarly with both insulins (HbA(1c), [reference range <6.5%] 8.3 +/- 0.1 vs. 8.2 +/- 0.1% at 1 year, glargine vs. NPH, mean +/- SEM, P < 0.001 vs. baseline for both). However, there was less nocturnal hypoglycemia (9.9 vs. 24.0% of all patients, glargine vs. NPH, P < 0.001) and lower post-dinner glucose concentrations (9.9 +/- 0.2 vs. 10.7 +/- 0.3 mmol/l, P < 0.02) with insulin glargine than with NPH. Insulin doses and weight gain were comparable. In patients reaching target FBG, HbA(1c) averaged 7.7 and 7.6% in the glargine and NPH groups at 1 year.Conclusions: Use of insulin glargine compared with NPH is associated with less nocturnal hypoglycemia and lower post-dinner glucose levels. These data are consistent with peakless and longer duration of action of insulin glargine compared with NPH. Achievement of acceptable average glucose control requires titration of the insulin dose to an FBG target < or =6.7 mmol/l. These data support use of insulin glargine instead of NPH in insulin combination regimens in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Objective: Nonalcoholic fatty liver disease (i.e., increased intrahepatic triglyceride [IHTG] content), predisposes to type 2 diabetes and cardiovascular disease. Adipose tissue lipolysis and hepatic de novo lipogenesis (DNL) are the main pathways contributing to IHTG. We hypothesized that dietary macronutrient composition influences the pathways, mediators, and magnitude of weight gain-induced changes in IHTG., Research Design and Methods: We overfed 38 overweight subjects (age 48 ± 2 years, BMI 31 ± 1 kg/m 2 , liver fat 4.7 ± 0.9%) 1,000 extra kcal/day of saturated (SAT) or unsaturated (UNSAT) fat or simple sugars (CARB) for 3 weeks. We measured IHTG ( 1 H-MRS), pathways contributing to IHTG (lipolysis ([ 2 H 5 ]glycerol) and DNL ( 2 H 2 O) basally and during euglycemic hyperinsulinemia), insulin resistance, endotoxemia, plasma ceramides, and adipose tissue gene expression at 0 and 3 weeks., Results: Overfeeding SAT increased IHTG more (+55%) than UNSAT (+15%, P < 0.05). CARB increased IHTG (+33%) by stimulating DNL (+98%). SAT significantly increased while UNSAT decreased lipolysis. SAT induced insulin resistance and endotoxemia and significantly increased multiple plasma ceramides. The diets had distinct effects on adipose tissue gene expression., Conclusions: Macronutrient composition of excess energy influences pathways of IHTG: CARB increases DNL, while SAT increases and UNSAT decreases lipolysis. SAT induced the greatest increase in IHTG, insulin resistance, and harmful ceramides. Decreased intakes of SAT could be beneficial in reducing IHTG and the associated risk of diabetes., (© 2018 by the American Diabetes Association.)

Objective: To compare the efficacy and safety of new insulin glargine 300 units/mL (Gla-300) with glargine 100 units/mL (Gla-100) in people with type 2 diabetes using basal insulin (≥42 units/day) plus oral antihyperglycemic drugs (OADs)., Research Design and Methods: EDITION 2 was a multicenter, open-label, two-arm study. Adults receiving basal insulin plus OADs were randomized to Gla-300 or Gla-100 once daily for 6 months. The primary end point was change in HbA1c. The main secondary end point was percentage of participants with one or more nocturnal confirmed (≤3.9 mmol/L [≤70 mg/dL]) or severe hypoglycemic events from week 9 to month 6., Results: Randomized participants (n = 811) had a mean (SD) HbA₁c of 8.24% (0.82) and BMI of 34.8 kg/m(2) (6.4). Glycemic control improved similarly with both basal insulins; least squares mean (SD) reduction from baseline was -0.57% (0.09) for Gla-300 and -0.56% (0.09) for Gla-100 (mean difference -0.01% [95% CI -0.14 to 0.12]), with 10% higher dose of Gla-300. Less nocturnal confirmed (≤3.9 mmol/L [≤70 mg/dL]) or severe hypoglycemia was observed with Gla-300 from week 9 to month 6 (relative risk 0.77 [95% CI 0.61-0.99]; P = 0.038) and during the first 8 weeks. Fewer nocturnal and any time (24 h) hypoglycemic events were reported during the entire 6-month period. Weight gain was lower with Gla-300 than with Gla-100 (P = 0.015). No between-treatment differences in safety parameters were identified., Conclusions: Gla-300 was as effective as Gla-100 and associated with a lower risk of hypoglycemia during the night and at any time of the day., (© 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Objective: To evaluate the efficacy and long-term safety of linagliptin added to basal insulins in type 2 diabetes inadequately controlled on basal insulin with or without oral agents., Research Design and Methods: A total of 1,261 patients (HbA1c ≥7.0% [53 mmol/mol] to ≤10.0% [86 mmol/mol]) on basal insulin alone or combined with metformin and/or pioglitazone were randomized (1:1) to double-blind treatment with linagliptin 5 mg once daily or placebo for ≥52 weeks. The basal insulin dose was kept unchanged for 24 weeks but could thereafter be titrated according to fasting plasma glucose levels at the investigators' discretion. The primary end point was the mean change in HbA1c from baseline to week 24. The safety analysis incorporated data up to a maximum of 110 weeks., Results: At week 24, HbA1c changed from a baseline of 8.3% (67 mmol/mol) by -0.6% (-6.6 mmol/mol) and by 0.1% (1.1 mmol/mol) with linagliptin and placebo, respectively (treatment difference -0.65% [95% CI -0.74 to -0.55] [-7.1 mmol/mol]; P < 0.0001). Despite the option to uptitrate basal insulin, it was adjusted only slightly upward (week 52, linagliptin 2.6 IU/day, placebo 4.2 IU/day; P < 0.003), resulting in no further HbA1c improvements. Frequencies of hypoglycemia (week 24, linagliptin 22.0%, placebo 23.2%; treatment end, linagliptin 31.4%, placebo 32.9%) and adverse events (linagliptin 78.4%, placebo 81.4%) were similar between groups. Mean body weight remained unchanged (week 52, linagliptin -0.30 kg, placebo -0.04 kg)., Conclusions: Linagliptin added to basal insulin therapy significantly improved glycemic control relative to placebo without increasing hypoglycemia or body weight.

Objective: To study the effect of exenatide on body composition and circulating cardiovascular risk biomarkers., Research Design and Methods: Metformin-treated patients with type 2 diabetes (N = 69) were randomized to exenatide or insulin glargine and treated for 1 year. Body composition was evaluated by dual-energy X-ray absorptiometry. Additionally, body weight, waist circumference, and cardiovascular biomarkers were measured., Results: Treatment with exenatide for 1 year significantly reduced body weight, waist circumference, and total body and trunkal fat mass by 6, 5, 11, and 13%, respectively. In addition, exenatide increased total adiponectin by 12% and reduced high-sensitivity C-reactive protein by 61%. Insulin glargine significantly reduced endothelin-1 by 7%. These changes were statistically independent of the change in total body fat mass and body weight., Conclusions: Exenatide treatment for 1 year reduced body fat mass and improved the profile of circulating biomarkers of cardiovascular risk. No significant changes were seen with insulin glargine except a trend for reduced endothelin-1 levels.

Objective: The purpose of this study was to determine whether type 2 diabetic patients have more liver fat than age-, sex-, and BMI-matched nondiabetic subjects and whether liver enzymes (serum alanine aminotransferase [S-ALT] and serum aspartate aminotransferase) are similarly related to liver fat in type 2 diabetic patients and normal subjects., Research Design and Methods: Seventy type 2 diabetic patients and 70 nondiabetic subjects matched for BMI, age, and sex were studied. Liver fat ((1)H-magnetic resonance spectroscopy), body composition (magnetic resonance imaging), and biochemical markers of insulin resistance were measured., Results: The type 2 diabetic patients had, on average, 80% more liver fat and 16% more intra-abdominal fat than the nondiabetic subjects. The difference in liver fat between the two groups remained statistically significant when adjusted for intra-abdominal fat (P < 0.05). At any given BMI or waist circumference, the type 2 diabetic patients had more liver fat than the nondiabetic subjects. The difference in liver fat between the groups rose as a function of BMI and waist circumference. Fasting serum insulin (r = 0.55, P < 0.0001), fasting plasma glucose (r = 0.29, P = 0.0006), A1C (r = 0.34, P < 0.0001), fasting serum triglycerides (r = 0.36, P < 0.0001), and fasting serum HDL cholesterol (r = -0.31, P = 0.0002) correlated with liver fat similarly in both groups. The slopes of the relationships between S-ALT and liver fat were significantly different (P = 0.004). Liver fat content did not differ between the groups at low S-ALT concentrations (10-20 units/l) but was 70-200% higher in type 2 diabetic patients compared with control subjects at S-ALT concentrations of 50-200 units/l., Conclusions: Type 2 diabetic patients have 80% more liver fat than age-, weight-, and sex-matched nondiabetic subjects. S-ALT underestimates liver fat in type 2 diabetic patients.

Objective: To compare the efficacy and safety of adding once-daily basal insulin versus switching to twice-daily premixed insulin in type 2 diabetic patients insufficiently controlled by oral antidiabetic agents (OADs)., Research Design and Methods: In a 24-week, multinational, multicenter, open, parallel group clinical trial, 371 insulin-naive patients with poor glycemic control (fasting blood glucose [FBG] >/=120 mg/dl, HbA(1c) 7.5-10.5%) on OADs (sulfonylurea plus metformin) were randomized to once-daily morning insulin glargine plus glimepiride and metformin (glargine plus OAD) or to 30% regular/70% human NPH insulin (70/30) twice daily without OADs. Insulin dosage was titrated to target FBG

Objective: Effects of weight loss on vascular function are unknown. We compared, in the face of similar weight loss over 3-6 months, effects of orlistat (120 mg t.i.d., n = 23) and placebo (n = 24) on in vivo endothelial function in a high-risk group of obese (BMI 32.1 +/- 0.4 kg/m(2)) premenopausal nondiabetic women with a history of gestational diabetes., Research Design and Methods: Forearm blood flow responses to intra-arterial infusions of acetylcholine (ACh) and sodium nitroprusside (SNP), body composition, and serum lipids were determined before and after weight loss., Results: Weight loss averaged 7.3 +/- 0.2 kg (8.3 +/- 0.1%) and 7.4 +/- 0.2 kg (8.2 +/- 0.1%) of initial body weight in the orlistat and placebo groups, respectively. Forearm and body compositions changed similarly in both groups. Responses to ACh increased by 41% to the low dose (5.9 +/- 0.6 vs. 8.3 +/- 0.3 for flow in the experimental/control arm, P < 0.01) and by 33% to the high dose (7.6 +/- 0.8 vs. 10.1 +/- 0.6, P < 0.001) in the orlistat group, but they remained unchanged in the placebo group. The blood flow responses to SNP did not differ significantly between the groups. LDL cholesterol decreased significantly in the orlistat group from 3.5 +/- 0.2 to 3.0 +/- 0.1 mmol/l (P < 0.01) but remained unchanged in the placebo group. Within the orlistat group, the decrease in LDL cholesterol correlated significantly with the improvement in the blood flow response to ACh (r = -0.44, P < 0.05)., Conclusions: Orlistat but not moderate (8%) weight loss per se improves endothelial function in women with previous gestational diabetes. This improvement is associated with a lowering of LDL cholesterol by orlistat.

Objective: To determine whether large arteries are resistant to insulin., Research Design and Methods: Insulin normally acutely decreases central systolic pressure by decreasing wave reflection in vivo. This effect occurs before any changes in peripheral vascular resistance or heart rate under normoglycemic conditions. We determined whether the ability of insulin to decrease central aortic pressure is altered in uncomplicated type 2 diabetes. The study subjects consisted of 16 type 2 diabetic patients (age 54 +/- 2 years, BMI 29 +/- 1 kg/m(2)) and 19 matched nondiabetic individuals (51 +/- 2 years, 29 +/- 1 kg/m(2)) studied under normoglycemic-hyperinsulinemic conditions. Central aortic pressure waveforms were synthesized from those recorded in the periphery using applanation tonometry and a validated reverse transfer function to construct the central aortic pressure waveform every 30 min. This method allowed determination of aortic augmentation (the pressure difference between the first and second central systolic pressure waves) and the augmentation index (augmentation divided by pulse pressure)., Results: Whole-body insulin sensitivity was 31% lower (P < 0.05) in the type 2 diabetic patients than in the normal subjects. Basally, before the insulin infusion, augmentation averaged 8.9 +/- 1.3 and 11.1 +/- 1.2 mmHg (NS) and the augmentation index averaged 23.1 +/- 2.1 and 27.5 +/- 2.1% (NS) in the normal subjects and diabetic patients, respectively. After 30 min of hyperinsulinemia, augmentation decreased significantly to 6.1 +/- 1.1 mmHg (P < 0.001) in the normal subjects but remained unchanged at 9.1 +/- 1.1 mmHg (NS) in type 2 diabetic patients. At 30 min, the augmentation index had decreased significantly (30 +/- 7% decrease) to 17.9 +/- 2.6% in the normal subjects but remained at 24.4 +/- 2.4% in the diabetic patients (13 +/- 4% decrease, P < 0.05 for change vs. normal subjects). Central systolic pressure decreased significantly by 30 min in the normal subjects but only after 120 min in the type 2 diabetic patients. There were no significant changes in heart rate, pulse pressure, or forearm blood flow during the first 120 min of the insulin infusion., Conclusions: Insulin resistance in type 2 diabetes involves a delay in the ability of insulin to decrease central aortic pressure. This defect could predispose these patients to develop systolic hypertension.

Objective: The question of whether to use insulin in the evening or in the morning during combination therapy in patients with non-insulin-dependent diabetes mellitus (NIDDM) is controversial. We compared the acute effects of 12-h nocturnal or daytime insulin infusions on the 24-h glucose profile in 20 patients with NIDDM., Research Design and Methods: NIDDM patients were 56 +/- 2 (mean +/- SE) years of age and had a body mass index of 29.6 +/- 1.1 kg/m2; fasting plasma glucose concentration of 12.2 +/- 0.5 mM; and fasting C-peptide concentration of 0.9 +/- 0.2 nM. Each patient was studied twice. On one occasion, the patient received a 12-h intravenous infusion of insulin (mean 1.5 +/- 0.1 IU/h) during the day, and on the other occasion an identical dose of insulin was infused during the night. Blood glucose, insulin, c-peptide, and free fatty acid concentrations were determined for 24 h., Results: The mean 24-h free insulin concentrations were similar in both studies (150 +/- 12 vs. 162 +/- 12 pM, daytime versus nocturnal insulin infusion). The mean 24-h free fatty acid concentration was 18% lower in the nocturnal than in the daytime (309 +/- 30 vs. 376 +/- 30 microM, P < 0.001) insulin infusion study. The mean 24-h C-peptide concentration was less suppressed if insulin was infused overnight than during the day (1.3 +/- 0.2 vs. 1.1 +/- 0.2 nM, P < 0.01). The mean 24-h plasma glucose concentrations were identical in both studies (11.1 +/- 0.6 vs. 11.4 +/- 0.7 mM, daytime versus nocturnal insulin infusion). We also searched for factors predicting the decrease in the blood glucose concentration during the nocturnal insulin infusion. The best predictors were a high initial blood glucose concentration at 2200 and a low fasting C-peptide concentration. These factors explained, independent of each other, 50% of the rate of decrease in the plasma glucose concentration., Conclusions: Despite better suppression of lipolysis and less suppression of endogenous insulin secretion by nocturnal than daytime insulinization, the hypoglycemic effect of these two treatments is similar.