[Response of insulin and C-peptide to a mixed meal in non-insulin-dependent diabetics treated with insulin and chlorpropamide]

Glucose control in NIDDM is prone to progressive deterioration due to secondary failure to oral hypoglycemic therapy. Insulin may subsequently be required for optimal control in spite of peripheral hyperinsulinemia. In Mexico, diabetes associated with obesity is common. We therefore designed a prospective study combining insulin and chloropropamide in order to evaluate any improvement in insulin response to a standardized meal load and a consequent amelioration of glucose control. METHODS. Twenty diabetic patients with secondary failure to full doses of hypoglycemic drugs and moderate hyperglycemia were recruited. Therapy was initiated with human insulin 20 IU/day and 500 mg cholopropamide, titrating insulin dosage in order to achieve euglycemia. Before treatment and at the end of the study period, a glucose/insulin/C peptide response curve to a mixed standardized meal was performed. Blood glucose, serum lipids fructosamine and glycosylated hemoglobin levels were also determined. All patients were followed by capillary glucose measurements three times a week and glucose and fructosamine concentrations every two weeks during the study period. RESULTS. All patients required less insulin, and glucose control improved significantly. Glucose, fructosamine and glycosylated hemoglobin levels decreased from 262 mg/dL, 369 mmol/L and 14% to 111 mg/dL, 252 mmol/L, and 8% respectively; all differences were statistically significant. Insulin and C peptide levels increased significantly from 22.2 mU/mL and 1.65 ng/mL to 29.8 mU/mL and 1.97 ng/mL, respectively. When we measured the area under the curve, total values improved from 110 and 7.69 to 127 and 9.37, respectively; this was also statistically significant. Lipids levels decreased significantly, including triglicerides, total and LDL cholesterol whereas HDL cholesterol levels increased. CONCLUSIONS. Glucose control improved in our patient cohort the pancreatic insulin response probably due to a more adequate glycemic microenvironment and a possible enhanced exogenous and endogenous insulin function.

Improved metabolic control does not reverse left ventricular filling abnormalities in newly diagnosed non-insulin-dependent diabetes patients

In this study left ventricular diastolic function at rest was evaluated in ten newly diagnosed, non-insulin-dependent diabetic patients by Doppler echocardiography, performed at the onset of disease and after 6 and 12 months of adequate glycaemic control. Glycosylated haemoglobin A1C, total cholesterol and triglyceride levels were assessed at the same time. The control group consisted of ten healthy subjects of matching age and body mass index. The following parameters of left ventricular function were evaluated: ejection fraction (EF), peak velocity of the early (E) and late atrial (A) mitral flow, A/E ratio, duration of the early (Ei) and of the atrial (Ai) filling phase, and heart rate. The diabetic patients had significantly higher total cholesterol and triglyceride levels compared with healthy subjects. These remained elevated throughout the follow-up period, in spite of improved glycaemic control. A significantly shorter duration of Ei (0.15 +/- 0.008 vs 0.18 +/- 0.004, P < 0.01) and a higher value of A (0.51 +/- 0.02 vs 0.39 +/- 0.01, P < 0.001) and A/E (1.06 +/- 0.05 vs 0.73 +/- 0.02, P < 0.001) were found in the diabetic patients before treatment. The parameters did not significantly change after 1 year of adequate glycaemic control. These results indicate a left ventricular filling abnormality which is present in newly diagnosed non-insulin-dependent diabetic patients and does not reverse with improved glycaemic control.

[A comparative evaluation of the hypoglycemic activity of acetyl-alpha-carnitine and chlorpropamide in experimental diabetes]

The comparison of the action shown by acetyl-alpha-carnitine and chloropropamide in rabbits with experimental diabetes has demonstrated that the former has a more pronounced hypoglycemic action. In combined administration, acetyl-alpha-carnitine substantially enhanced the effects of chloropropamide in the animals with experimental diabetes, which should be taken into account by clinicians in its use.

Administration of sulfonylureas can increase glucose-induced insulin secretion for decades in patients with maturity-onset diabetes of the young

OBJECTIVE

To ascertain whether the effect of sulfonylureas on glucose-mediated insulin release persists for years to decades in patients with maturity-onset diabetes of the young.

RESEARCH DESIGN AND METHODS

The effect of sulfonylurea treatment on glucose-induced insulin secretion was ascertained prospectively for up to 33 yr in 12 diabetic patients of the maturity-onset diabetes of the young RW pedigree, who are genetically homogeneous because they share DNA markers on chromosome 20q. In 7 of these patients, paired glucose tolerance tests, given while the patients were on and off sulfonylureas, were performed after 7-31 yr.

RESULTS

Glucose-induced insulin secretion showed an average increase of 68% in diabetic patients who remained responsive to chlorpropamide after having been on and off the drug for decades. In most patients, however, glucose-induced insulin secretion declines over time (1-4%/yr). Some patients become unresponsive to sulfonylureas after 3-25 yr and then have very small or no increases in glucose-induced insulin secretion and require treatment with insulin to normalize fasting hyperglycemia.

CONCLUSIONS

Increase in glucose-induced insulin secretion remains the most important mechanism of the action of sulfonylureas during long-term administration.

Hypertension secondary to chlorpropamide with amelioration by changing to insulin

A retrospective analysis of the records of 22 type II diabetics whose treatment had been changed from insulin to chlorpropamide was performed to investigate the relative effects of insulin and chlorpropamide on blood pressure. Although diastolic BP index was not significantly different between the treatments, systolic BP index was significantly higher on chlorpropamide than on insulin (141 +/- 3 v 135 +/- 3 mm Hg, P = .02). In 10 patients in whom insulin was reinstituted, systolic BP fell significantly (P < .005), suggesting that in type II diabetics chlorpropamide exerts a relative hypertensive effect in comparison to insulin.

Weight loss reverses secondary failure of oral hypoglycaemic agents in obese non-insulin-dependent diabetic patients independently of the duration of the disease

The aim of the present study was to evaluate whether reduction of body weight is able to restore sensitivity to oral hypoglycaemic agents in obese non-insulin-dependent diabetic patients with secondary failure of to the anti-diabetic drugs. 80 obese patients (BMI approximately 30 kg/m2) with Type 2 diabetes lasting 1-30 years and showing hyperglycaemia for at least 3 months (51 on insulin, 29 on oral drugs) received an 800 kcal diet for 20-24 days, lost about 6.3% BMI, and returned to euglycaemia; 22 obese euglycaemic Type 2 diabetes patients (9 on insulin, 13 on oral therapy) underwent the same treatment, and lost approximately 8.3% BMI. As a result insulin could be withdrawn in 18 out of 60 patients and reduced (from 0.5 to 0.2 U.kg day) in the remaining patients. Oral therapy could be withdrawn in 17 out of 42 cases and reduced (from 12.1 to 8.6 mg glibenclamide/day) in the remaining cases. As a control group, 20 non obese (BMI < 24.0 kg/m2) hyperglycaemic Type 2 diabetic patients (10 on oral hypoglycaemic agents, 10 on insulin) with Type 2 diabetes lasting 1-26 years, underwent the same dietary regimen, lost about 3.2% of body weight, but could not withdraw insulin, which had to be started in 6 previously oral hypoglycaemic drugs treated patients. Systolic and diastolic blood pressure and serum cholesterol and triglyceride levels also decreased in obese, but not in non-obese Type 2 diabetes patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of bed time intermediate acting insulin in NIDDM subjects refractory to a combination of sulphonylureas and biguanides

The effect of a single dose of intermediate acting (Lente) insulin given subcutaneously at 9.00 P.M. in 22 NIDDM subjects refractory to a combination of Sulphonylureas and Biguanides was analysed. Euglycemia was achieved and maintained during the study period of three months with a mean insulin requirement of 14.22 +/- 5.98 units/day. Plasma FFA, Total cholesterol, triglyceride and VLDL-cholesterol also showed significant reduction. The level of FFA modulates hepatic glucose production, which in turn correlates positively with the fasting blood glucose. The therapeutic modality of bed time Lente Insulin based on physiological principles is an effective way of achieving glycemic control in NIDDM subjects who have become non-responsive to oral hypoglycemic agents.

Risk factors for hyperinsulinemia in chlorpropamide-treated diabetic patients: a three-year follow-up

To elucidate the presence of chronic hyperinsulinemia and its relation to clinical and biochemical parameters, 112 (53 females and 59 males) Chinese non-insulin-dependent diabetes mellitus (NIDDM) patients under chlorpropamide therapy were closely monitored for three years. Clinical and biochemical risk factors for chronic hyperinsulinemia were studied by regular monitoring of body weight, fasting insulin levels and various biochemical data. Chronic hyperinsulinemia was defined as a mean fasting level over 20 microU/mL (highest level observed in 35 non-diabetics). Among 112 diabetics, 52 cases (46.4%) showed chronic hyperinsulinemia. From simple linear regression analysis, female gender, high BMI and elevated triglyceride and uric acid levels were correlated with insulin levels (p < 0.05). The presence of diabetic complications (retinopathy, neuropathy and nephropathy) and the degree of glycemic control were not significantly different between the normoinsulinemic and hyperinsulinemic groups. In conclusion, 1) NIDDM patients treated with chlorpropamide showed higher fasting insulin levels with 46.4% of them meeting the criteria for chronic hyperinsulinemia; 2) female gender, uric acid, BMI and triglyceride were the risk factors correlated with chronic hyperinsulinemia; and 3) the presence of diabetic complications and diabetic control correlated poorly with chronic hyperinsulinemia.

Is combination sulfonylurea and insulin therapy useful in NIDDM patients? A metaanalysis

OBJECTIVE

To assess the efficacy of combination therapy with insulin and sulfonylurea in the treatment of NIDDM.

RESEARCH DESIGN AND METHODS

Studies published between January 1966 and January 1991 were identified through a computerized Medline search and by hand searching the bibliographies of identified articles. We identified 17 eligible randomized, controlled trials of combination therapy in NIDDM. These trials had a minimum duration of 8 wk and at least one of three outcome measures (fasting glucose, HbA1, or C-peptide) with SD or SE of the mean reported to do metaanalysis. With standardized forms, three independent reviews abstracted measures of study quality and specific descriptive information about population, intervention, and outcome measurements.

RESULTS

We calculated effect size and weighted mean changes of the three outcome measures for control and treatment groups. In the treatment group, the fasting plasma glucose decreased from a mean of 11.4 mM (206 mg/dl) at baseline to a mean of 9.16 mM (165 mg/dl) posttreatment, whereas the control group decreased from (11.3 to 10.8 mM) (204 to 194 mg/dl) (effect size 0.39, P less than 0.0001). For HbA1, the treatment group decreased from a baseline of 11.0 to 10.2% compared to 11.0 and 11.2% in the control group (effect size 0.43, P less than 0.0001). For fasting C-peptide, the treatment group increased from 0.49 to 0.58 nM (1.45 to 1.75 ng/ml) compared with 0.47 and 0.43 (1.42 and 1.30) for the control group (effect size 0.26, P less than 0.017).

CONCLUSION

Combined insulin-sulfonylurea therapy leads to modest improvement in glycemic control compared with insulin therapy alone. With combined therapy, lower insulin doses may be used to achieve similar control. Obese patients with higher fasting C-peptides may be more likely to respond than others.

Combination daytime chlorpropamide-metformin/bedtime insulin in the treatment of secondary failures in non insulin dependent diabetes

OBJECTIVES

To determine the effectiveness of the combination therapy with daytime chlorpropamide-metformin and bedtime NPH insulin in the treatment of secondary failures in NIDDM and to study its effects on insulin secretion.

DESIGN

Non randomized open study with a duration of two months. The patients were followed six months after ending the study.

INSTITUTION

Department of Diabetes and Lipid Metabolism. Instituto Nacional de la Nutrición "Salvador Zubirán", Mexico City. CHARACTERISTICS OF THE PATIENTS: Nine patients (seven women and two men) were included. All had NIDDM and secondary failure to antidiabetic oral drugs. Their fasting plasma glucose was 14.5 +/- 2 mM/L and their HbA1c 13.37 +/- 2.9%. At the entry and at the end of the study a 5h-OGTT was done with assays of plasma glucose and C-peptide.

TREATMENT

Chlorpropamide (375 mg/day) plus metformin (1200 mg/day) and bedtime insulin (0.1 U/kg/day).

RESULTS

After two months on combination therapy, fasting plasma glucose and HbA1c levels were remarkably improved (decreases of 7.3 +/- 0.6 and 9.1 +/- 1.02 respectively, p less than 0.002). The insulin dose was small (6.77 +/- 2.09 U/day). Side effects were minimal and infrequent. During the 5h-OGTT, the mean glucose area under the curve also decreased. The insulin secretion did not change but the C-peptide/glucose ratio increased. At the end of the study, the insulin dose was tapered off and stopped when possible. The four patients with the best glycemic control during the study were able to suspend the bedtime insulin and maintain a good control six months after the insulin suspension.

CONCLUSIONS

The combination therapy is useful in the treatment of secondary failures in NIDDM: Its advantages are the very low mean daily insulin dose needed, the low incidence of side effects and, if a HbA1c less than 8.7% is achieved, the restoration of oral antidiabetic drugs efficacy. The very low insulin dose used in this study could be explained by complementary effects of metformin and bedtime insulin on hepatic glucose output and a putative decrease in peripheral resistance attributable both to sulfonylurea and metformin.

[The efficacy of quercetin in alloxan diabetes]

It has been established that quercetin in doses of 10 and 50 mg/kg promotes normalization of the level of glycemia and blood coagulation, increases liver glycogen content, reduces high blood serum concentrations of cholesterol and low density lipoproteins, seen in diabetes. In some cases, the efficacy of quercetin exceeds that of chlorpropamide and dry Eleutherococcus extract in white rats with alloxan diabetes.

Chlorpropamide induced syndrome of inappropriate secretion of antidiuretic hormone

This is a report of a patient who developed symptomatic hyponatraemia during chlorpropamide therapy for diabetes mellitus. The patient's clinical and biochemical abnormalities were corrected by withdrawal of chlorpropamide. This represents a drug induced, reversible form of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH).

Efficacy of gliclazide in comparison with other sulphonylureas in the treatment of NIDDM

Three studies were performed to assess the efficacy of various sulphonylureas in the management of diet-failed NIDDM patients. In the first study, 224 patients inadequately controlled by diet alone or with oral hypoglycaemics received gliclazide in addition to diet or in place of existing drugs for three months. The dosage was adjusted to obtain adequate control or up to the maximum recommended dosage. Good glycaemic control was achieved in 65% of patients. Conversion from other oral hypoglycaemics to gliclazide led to an improvement in control except in cases previously treated with glibenclamide. In the second study, diabetic control was compared in 112 NIDDM patients treated concurrently for one year with chlorpropamide, glipizide, gliquidone, glibenclamide or gliclazide. On the basis of HbA1 levels, the best results were obtained with glibenclamide and gliclazide, leading to normal HbA1 levels in 74% and 80% of patients, respectively. In the third study, secondary failure rates were assessed in 248 NIDDM patients treated for five years with gliclazide, glibenclamide or glipizide. Gliclazide had the lowest secondary failure rate (7%) and was significantly better than glipizide (25.6% failures in five years), but the difference relative to glibenclamide (17.9%) just failed to reach the threshold of significance. The results of these studies show that gliclazide is a potent hypoglycaemic agent which compares favourably with others of its type. It has a low incidence of side effects, few problems with hypoglycaemia, and retains its efficacy longer than other sulphonylureas. Gliclazide may therefore be considered a first choice for the therapy of diet-failed NIDDM patients.

Effects of lovastatin in diabetic patients treated with chlorpropamide

Patients with non-insulin dependent diabetes mellitus (NIDDM) have a higher risk of atherosclerotic cardiovascular disease than nondiabetic subjects. In seven patients with both hypercholesterolemia and NIDDM controlled by chlorpropamide, lovastatin (20 mg b.i.d. for 6 weeks) lowered low-density lipoprotein cholesterol by 28%, total cholesterol by 24%, and apolipoprotein B by 24%. Lovastatin levels for a 4-hour period (measured as 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitory activity) were similar to those measured previously in nondiabetic patients. Lovastatin did not alter chlorpropamide kinetics or glycemic profiles. No patient had an elevation in serum transaminases or creatinine phosphokinase, and no patient had any other laboratory or clinical drug-related adverse experience during the study. Lovastatin was as effective in reducing low-density lipoprotein cholesterol in patients with NIDDM as in nondiabetic subjects. Diabetic control was unaltered, and no evidence of alteration in lovastatin or chlorpropamide blood levels was noted.

The individual over time: time series applications in health care research

This paper presents a summary and a brief theoretical introduction to time series ARIMA modeling of single subject data. Time series, a statistical technique that may be appropriate when data are measured repeatedly and at nearly equal intervals of time, has potential research applications in the study of chronic diseases such as diabetes, hypertension, and herpes simplex. Both intervention models and multivariate models are covered, with examples illustrating the utility of time series techniques in chronic disease research. Time series modeling of a subject with diabetes before and after being placed on a regimen of chlorpropamide is used to demonstrate the potential of intervention analysis. Multivariate time series techniques are illustrated by modeling the relationship between exercise and blood glucose, and by modelling the relationship between psychosocial distress and lymphocyte subsets of the cellular immune system.

Transient neonatal diabetes mellitus in a pair of twins

The occurrence of transient neonatal diabetes mellitus in male twins with almost identical courses of illness is reported. A trial with chlorpropamide treatment of twin A had no obvious influence on the insulin consumption or on duration of treatment. Very low values of plasma C-peptide and serum proinsulin with no detectable insulin antibodies supports the theory of delayed maturation of the beta-cell.

Prolonged cholestasis and disappearance of interlobular bile ducts following chlorpropamide and erythromycin ethylsuccinate. Case of drug interaction?

A 52-year-old man, having been treated for 4 months with chlorpropamide for diabetes mellitus type II, developed severe cholestatic hepatitis following a short course of erythromycin ethylsuccinate. Despite prompt withdrawal of both drugs, the cholestatic picture worsened and was associated with morphological evidence of disappearing interlobular bile ducts. After a 2-year course of profound cholestasis complicated by steatorrhea and striking hyperlipidemia, the patient died of ischemic cardiomyopathy. It is believed that this is the first published case of irreversible cholestasis with disappearance of ducts potentially related to a metabolic interaction between erythromycin ethylsuccinate and chlorpropamide.

Lactic acidosis due to metformin therapy in a low risk patient

A 55 year old diabetic women treated with chlorpropamide and metformin for three years presented with acute oliguric renal failure and lactic acidosis from which she died. The plasma metformin level was very high suggesting that the lactic acidosis was caused by the drug. There were no contraindications to metformin therapy and renal function was normal three months previously. This case demonstrates that lactic acidosis can occur as a result of metformin therapy in the absence of pre-existing risk factors.

Association of hyperinsulinemia with chlorpropamide toxicity

Clinical and metabolic features of chlorpropamide toxicity are described in two patients with diabetes mellitus and accidental chlorpropamide overdosage. Elevated serum insulin levels were found during hypoglycemia in both patients. The world's literature was reviewed for other cases of chlorpropamide toxicity in which insulin levels have been measured during hypoglycemia. A consistent feature of chlorpropamide toxicity is hyperinsulinemia. It is concluded that stimulation of the pancreatic beta cells during chlorpropamide toxicity leads to hyperinsulinemia and hypoglycemia.

Modification of therapy from insulin to chlorpropamide decreases HDL cholesterol in patients with non-insulin-dependent diabetes mellitus

In 27 patients with non-insulin-dependent diabetes mellitus, we determined fasting serum glucose, hemoglobin A1, body weight, serum triglycerides, cholesterol, low-density lipoprotein cholesterol (LDL-chol), high-density lipoprotein cholesterol (HDL-chol), and very-low-density lipoprotein cholesterol during treatment with insulin and several months after changing treatment to chlorpropamide. In five patients, diabetic control deteriorated to the point where insulin was reinitiated. In the remaining 22 patients, despite a significant decrease in weight (122 +/- 5 vs. 114 +/- 5% ideal body wt; P less than .025) on chlorpropamide, HDL-chol fell from 49 +/- 4 to 40 +/- 4 mg/dl (P less than .01) when therapy was modified from insulin to the sulfonylurea. There was a concomitant increase in LDL-chol:HDL-chol from 3.6 +/- 0.3 to 4.4 +/- 0.5 (P less than .05). In the 5 patients in whom insulin was reinstituted, HDL-chol increased to its previous level on insulin (P less than .05). Changing antidiabetic medication from insulin to sulfonylureas may alter the lipoproteins in a manner that increases cardiovascular risk.

Glyburide and glipizide in treatment of diabetic patients with secondary failures to tolazamide or chlorpropamide

We evaluated therapeutic usefulness of the second-generation sulfonylurea agents glyburide and glipizide in non-insulin-dependent diabetic patients who were secondary failures on chlorpropamide or tolazamide. Twenty patients were treated with glyburide, and 10 of them were subsequently treated with glipizide. Fasting and postprandial serum glucose, insulin, C-peptide, glycosylated hemoglobin, urinary C-peptide, and glucose levels all failed to show significant improvement. We concluded that both glyburide and glipizide proved ineffective in the treatment of secondary failures to first-generation sulfonylureas.