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Results for “Glycemic Control”

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At least 163 records · Page 9Linked to original sources

PubMed1998

Improved glycemic control with insulin aspart: a multicenter randomized double-blind crossover trial in type 1 diabetic patients. UK Insulin Aspart Study Group.

OBJECTIVE: To compare glycemic control obtained with the new rapid-acting insulin analog insulin aspart with that obtained with unmodified human insulin using algorithm-driven dosage adjustment. RESEARCH DESIGN AND METHODS: This was a multicenter randomized double-blind crossover study of 90 male subjects with type 1 diabetes. Insulin aspart or soluble human insulin was administered before meals, and NPH insulin was administered at bedtime as basal therapy. Each 4-week study period ended with a 24-h inpatient serum insulin and plasma glucose profile. RESULTS: The 24-h plasma glucose control obtained with insulin aspart, as assessed by excursions of blood glucose outside a predefined normal range (4.0-7.0 mmo/l), was superior (22% reduction in excursion, P < 0.01). Fructosamine levels remained unchanged with insulin aspart, with daytime glycemic control superior but nighttime glycemic control inferior. Eight-point home blood glucose profiles confirmed that insulin aspart significantly improved postprandial blood glucose control after lunch and dinner (P < 0.05) without deterioration of preprandial blood glucose control. Hypoglycemic episodes requiring third-party intervention were significantly fewer with insulin aspart than with human insulin (20 vs. 44 events, P < 0.002). Insulin aspart was well tolerated. CONCLUSIONS: In comparison with human insulin, insulin aspart can improve postprandial glycemic control as assessed by a reduction in hyper- and hypoglycemic excursions in people with type 1 diabetes. For its full potential to be realized, it will need to provide better control of nighttime hyperglycemia.

Adult↗

PubMed1990

Minor congenital malformations in infants of insulin-dependent diabetic women: association with poor glycemic control.

A prospective study of 171 insulin-dependent diabetic pregnant women was undertaken to establish the relationship of glycemic control with minor congenital malformations. Each live-born infant was assessed systematically by two independent examiners using a standardized checklist. There were 32 infants with minor congenital malformations (18.7%). There were significant differences in mean glycohemoglobin A1 between the group with minor congenital malformations and the group without congenital malformations at 12, 16, and 20 weeks, but not at 8 or 24 weeks. Logistic regression analysis showed that maternal age, race, gravidity, White class, duration of diabetes, maternal vasculopathy, and cigarette smoking were not significant variables correlated with minor congenital malformations. Because glycohemoglobin levels from 12-20 weeks are believed to reflect glycemic control from approximately 6-20 weeks, we conclude that poor glycemic control during late embryogenesis and early fetal development is associated with an increased risk of minor congenital malformations. We speculate that improvement of glycemic control during this period should decrease the risk of minor congenital malformations.

Blood Glucose↗

PubMed2006

Economic impact of antidiabetic medications and glycemic control on managed care organizations: a review of the literature.

OBJECTIVE: To review the recent literature (January 2000-November 2005) regarding the impact of antidiabetic medications and glycemic control on the overall costs of care for patients with diabetes in U.S. managed care organizations (MCOs). SUMMARY: The pharmacy component accounts for typically 20% to 30% (full range, 10%-65%) of overall costs for MCO patients with diabetes. About 30% of pharmacy expenses are directly related to glycemic control, while the balance is spent on the management of macrovascular and microvascular complications related to diabetes and other common comorbidities such as hypertension and hyperlipidemia. Cost offsets and/or cost savings have been shown with the initiation of insulin therapy, including the use of newer short-acting insulins. Increasing medication possession ratios for antidiabetic medications (including insulins) are correlated with reduced overall health care costs, particularly reductions in hospitalization rates. Patients with diagnosed diabetes not receiving medications have significantly increased health care resource utilization. We identified 8 studies that indicatred that improvements in glycemic control lower overall per-patient direct costs within MCOs. CONCLUSIONS: The literature to date suggests that improving glycemic control and antidiabetic medication persistence reduce overall medical costs for patients with diabetes in managed care plans. Continued expansion of antidiabetic medication options will place increasing pressure on MCOs to assess the return on investment for newer pharmacotherapies. Routine measurement of economic and quality-of-life outcomes alongside clinical outcomes will become necessary for assessing the total value that new antidiabetic medications provide and whether cost offsets to managed care exist. Appropriate use of antidiabetic medications, including medication compliance, is an important component in a strategy to achieve glycemic control and may improve outcomes for patients with diabetes.

Blood Glucose↗

PubMed2002

Anxiety and poor glycemic control: a meta-analytic review of the literature.

OBJECTIVE: To determine whether anxiety is associated with poor glycemic control in adults with type 1 or type 2 diabetes. METHOD: MEDLINE, PubMed, and PsycINFO databases were used to locate studies that measured the association of anxiety with glycemic control. Meta-analytic procedures were used to convert the findings to a common metric, compute effect sizes (ES), and statistically analyze the collective data. RESULTS: The search procedures identified 12 studies, 11 (92 percent) of which satisfied the criteria for inclusion in the meta-analysis. In this overall group, anxiety was not associated with glycemic control (p = 0.19), although the ES was marginally statistically significant (ES = .09, 95 percent CI = 0.04 to 0.14). In studies that determined anxiety from diagnostic interviews, anxiety was associated with hyperglycemia (p = 0.003) and the ES was also statistically significant (ES: 0.25, 95 percent CI = 0.10 to 0.38). CONCLUSIONS: The existing literature suggests that anxiety disorders are associated with hyperglycemia in diabetic patients. Additional studies are required to confirm the magnitude of the relationship, to elucidate moderating and causal factors, and to determine whether successful treatment of anxiety improves glycemic control.

Anxiety↗

PubMed2005

Monitoring glycemic control: the cornerstone of diabetes care.

BACKGROUND: Diabetes mellitus is associated with significant morbidity and mortality and escalating costs, and its prevalence is increasing to epidemic proportions. Studies have consistently documented the importance of glycemic control in delaying the onset and decreasing the incidence of both the short- and long-term complications of diabetes. Although glycemic control is difficult to achieve and challenging to maintain, its impact on disease outcomes is well worth the effort. OBJECTIVE: This article reviews the importance of monitoring and tightly controlling blood glucose concentrations in patients with diabetes and the methods and tools available for achieving these goals. METHODS: This clinical review was developed using 102 a MEDLINE search of the literature from 1990 to 2005 using the terms diabetes, glucose control, glucose monitoring, A(1c), and hypoglycemia. RESULTS: The complications of diabetes can be prevented or sharply curtailed through tight glycemic control, which requires frequent monitoring of blood glucose levels, careful attention to diet and exercise, and the use of medications. The progressive nature of diabetes imposes the need for frequent and regular monitoring, leading to data-driven adjustments to therapy to maintain optimal glucose levels. Failure to achieve glycemic control is often the result of a failure to educate the patient about how to monitor blood glucose levels and the importance of accuracy in doing so. CONCLUSIONS: Tight glycemic control requires an 102 educated and motivated patient, an appropriate treatment regimen, vigilant monitoring, and a close partnership between the patient and a multidisciplinary team of health care professionals to ensure accurate monitoring and appropriate actions. The growing array of monitoring devices contributes to this effort by providing increased convenience and accuracy.

Algorithms↗

PubMed1995

Long-term glycemic control relates to mortality in type II diabetes.

OBJECTIVE: To study the influence of long-term glycemic control on mortality in a cohort of newly detected type II diabetic individuals. RESEARCH DESIGN AND METHODS: A total of 411 newly detected type II diabetic individuals diagnosed between 1972 and 1987 were followed until 31 December 1989. Clinical data concerning fasting blood glucose (FBG) values, body mass index (BMI), type of treatment, and concomitant diseases were collected during 8 randomly selected years. Long-term glycemic control was measured as annual averages of FBG values during these years. Mortality data were obtained from official registers. RESULTS: There were 161 diabetic subjects who died during a mean follow-up time of 7.4 years. In univariate analyses, higher age at diagnosis; higher baseline or average FBG; and the presence of heart disease, cerebrovascular disease, or kidney disease at the beginning or during the course of diabetes were related to higher mortality. Type of diabetes treatment or having a diagnosis of hypertension was not related to mortality. In multiple logistic regression analyses, age at diagnosis and average FBG were independently related to all-cause (P = 0.0002), cardiovascular (P = 0.0006), and ischemic heart disease mortality (P = 0.03). No correlations between glycemic control and noncardiovascular deaths were found. In a Cox's regression analysis, average FBG was significantly related to length of survival when age at diabetes diagnosis was taken into account (P < 0.05). Diabetic subjects with average FBG > or = 7.8 mmol/l had 50% higher mortality compared with diabetic subjects with average FBG < 7.8 mmol/l. CONCLUSIONS: Diabetic patients with good long-term glycemic control had a better survival rate than subjects with high average FBG values. The findings should be interpreted cautiously because possible confounding factors such as dyslipoproteinemia and smoking were not studied.

Adult↗

PubMed2001

The influences of obesity and glycemic control on endothelial activation in patients with type 2 diabetes.

The aims of this study were to elucidate the factors that contribute to endothelial activation and fibrinolytic abnormalities in patients with poorly controlled type 2 diabetes and to determine whether improved glycemic control reduces endothelial activation. Adhesion molecules [E-selectin, intracellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1], von Willebrand factor, total nitric oxide (NO), endothelin-1, tissue plasminogen activator, and plasminogen activator inhibitor-1 were measured in 43 type 2 diabetic subjects with hemoglobin A1c of 9.0% or more at baseline (compared with 21 healthy controls) who after 20 wk had been randomized to either improved (IC) or usual (UC) glycemic control. At baseline, type 2 diabetic patients had significant endothelial activation and abnormal fibrinolysis compared with control subjects. Body mass index in the diabetic patients was the only independent predictor of E-selectin (P = 0.007), ICAM-1 (P = 0.01), and NO (P = 0.008) concentrations, but not vascular cell adhesion molecule-1, plasminogen activator inhibitor-1, or tissue plasminogen activator (all P > 0.05). Type 2 diabetic patients with a body mass index of 28 kg/m2 or less had concentrations of E-selectin, ICAM-1, endothelin-1, and NO similar to those in healthy controls. After 20 wk, hemoglobin A1c was significantly lower in IC vs. UC (IC, 8.02 +/- 0.25%; UC, 10.23 +/- 0.23%; P < 0.0001), but there were no significant changes in markers of endothelial activation or indexes of fibrinolysis. Obesity appears to be the most important predictor of endothelial activation in patients with type 2 diabetes. Short-term improvement in glycemic control does not appear to reduce endothelial activation.

Biomarkers↗

PubMed2006

[Predictive factors of glycemic control in patients with type 2 diabetes mellitus in primary health care].

PURPOSE: To determine the factors associated with poor glycemic control in type 2 diabetic patients followed in primary care units in Sousse, Tunisia. METHODS: A cross-sectional study was conducted on a representative sample of type 2 diabetic patients followed at least two years in primary health care units in Sousse, Tunisia. Data were gathered from three sources: a self-administrated questionnaire, analysis of patient files and HbA1c level. HbA1c level was measured with turbidimetric immunoinhibition assay. Patients were considered well-controlled if glycated hemoglobin (HbA1c) was less than 7%, according to the American Diabetics Association (ADA) recommendations. RESULTS: The study enrolled 404 type 2 diabetic patients. The mean age was 60.5+/-10.89 years, sex-ratio was 0.5, and mean disease duration 8.7+/-6.1 years. ADA recommendations were met by 16.7% of patients. Multivariate analysis using variables in relation with the patient, his/her family, the disease, the treatment and the health care unit, showed that only poor geographic access to the care center (adjusted OR: 1.89, p=0.009) and Body Mass Index (BMI) less than 30 kg/m2 (adjusted OR: 2.21, p=0.034) were significantly and independently associated with poor glycemic control. CONCLUSION: Glycemic control in type 2 diabetic patients is poor. It depends strongly on geographic access to health care. Type 2 diabetic patients should be referred, as much as possible, to the nearest health care unit.

Adult↗

PubMed2004

Optimal glycemic control is associated with a lower rate of target vessel revascularization in treated type II diabetic patients undergoing elective percutaneous coronary intervention.

OBJECTIVES: We examined the association between glycemic control determined by preprocedural hemoglobin A1c (A1c) and the incidence of target vessel revascularization (TVR) in diabetic patients undergoing elective percutaneous coronary intervention (PCI). BACKGROUND: Patients with diabetes mellitus (DM) have increased rates of restenosis and a worse clinical outcome after PCI than patients without DM. METHODS: A total of 239 patients (60 without DM and 179 with DM) were enrolled in this study. Optimal glycemic control was defined as A1c < or =7%, and suboptimal control was defined as A1c >7%. Follow-up was performed at six and 12 months after the index intervention. RESULTS: Diabetic patients with optimal glycemic control had a rate of 12-month TVR similar to that of nondiabetic patients (15% vs. 18%, p = NS). Diabetic patients with A1c >7% had a significantly higher rate of TVR than those with A1c <7% (34% vs. 15%, p = 0.02). In a multiple logistic regression analysis, A1c >7% was a significant independent predictor of TVR (odds ratio 2.87, 95% confidence interval 1.13 to 7.24; p = 0.03). Optimal glycemic control was associated with a lower rate of cardiac rehospitalization (15% vs. 31%, p = 0.03) and recurrent angina (13% vs. 37%, p = 0.002) at 12-month follow-up. CONCLUSIONS: In diabetic patients undergoing elective PCI, optimal glycemic control (A1c < or =7%) is associated with a lower rate of TVR, cardiac rehospitalization, and recurrent angina. These data suggest that aggressive treatment of DM to achieve A1c < or =7% is beneficial in improving the clinical outcome after PCI.

Aged↗

PubMed2005

Effect of glycemic control on left ventricular diastolic function in type 1 diabetes mellitus.

Left ventricular (LV) diastolic dysfunction is a main feature of diabetic heart disease. The aim of this prospective study was to evaluate the influence of glycemic control on diastolic function in type 1 diabetes mellitus. Thirty-six normotensive (24-hour blood pressure <130/80 mm Hg) subjects with inadequately controlled (glycated hemoglobin >7%) type 1 diabetes, without clinically detectable heart disease, were enrolled. After the basal evaluation, insulin therapy was modified to improve glycemic control. Glycated hemoglobin, LV echocardiography, 24-hour blood pressure monitoring, and laboratory tests were repeated after 6 months in all patients and after 12 months in 27 patients. At the basal evaluation, LV anatomy and systolic function were normal in all, and diastolic function was impaired in 14 patients. After 6 months, the mean values of body mass index, 24-hour blood pressure, and LV anatomy and systolic function were unchanged; mean glycated hemoglobin was decreased (p < 0.001), and mean values of diastolic parameters were significantly improved. After 12 months, the mean values of all blood pressure, metabolic, and LV parameters were unchanged. Percent changes of diastolic parameters were inversely correlated with percent changes of glycated hemoglobin, considering changes from the basal to the 6-month evaluation, as well as changes from the 6- to the 12-month evaluation. In conclusion, in normotensive patients with type 1 diabetes, a close relation was found between glycemic control and LV diastolic function, which improves when glycemic control improves. Therefore, diastolic dysfunction can be prevented or reversed, at least partly, by tight glycemic control.

Adult↗

PubMed1995

Differential regulation of counterregulatory hormone secretion and symptoms during hypoglycemia in IDDM. Effect of glycemic control.

OBJECTIVE: To determine 1) if there was a differential effect of glycemic control on individual counterregulatory hormone responses to hypoglycemia in patients with insulin-dependent diabetes mellitus (IDDM), 2) whether these modifications affect hypoglycemic symptom perception, and 3) if there was a level of glycemic control below which counterregulatory and symptomatic responses to hypoglycemia become consistently altered. RESEARCH DESIGN AND METHODS: We performed hypoglycemic clamp studies on 38 patients with IDDM and 38 healthy control subjects. Glucose was lowered from 5.0 to 2.2 mmol/l over 3 h in decrements of 0.6 mmol/l each 30 min. Epinephrine, cortisol, growth hormone (GH), glucagon, and symptom score were measured at each glucose plateau. RESULTS: In IDDM patients, HbA1 levels were positively correlated with incremental epinephrine (r = 0.58, P < 0.001) and cortisol (r = 0.52, P < 0.01) responses, but inversely correlated with GH responses (r = -0.31, P < 0.05). The increase in symptom score correlated with the epinephrine response in the IDDM patients (r = 0.57, P < 0.001), but not in the healthy control subjects (r = -0.02, NS). In IDDM patients with HbA1 < or = 7.8% (n = 7), the epinephrine, cortisol, and symptomatic responses to hypoglycemia were blunted, but GH secretion was preserved. CONCLUSIONS: These data suggest that 1) there is differential regulation of counterregulatory hormone secretion that is dependent on the level of glycemic control, 2) epinephrine is an important determinant of symptom perception in IDDM patients, but not in healthy control subjects, and 3) multiple defects in counterregulatory hormone secretion and symptom perception are consistently observed in patients with HbA1 levels < or = 7.8%.

Adult↗

PubMedDate not supplied

Depressed mood is a factor in glycemic control in type 1 diabetes.

OBJECTIVE: The diabetes literature contains conflicting evidence on the relationship between depression and glycemic control. This may be due, in part, to the fact that past studies failed to distinguish between patients with type 1 and type 2 diabetes. Because these are actually completely different diseases that are often treated differently and consequently make different demands on patients, the relationship between glycemic control and depressed mood in type 1 and type 2 diabetes was examined separately. METHODS: The relationship between Beck Depression Inventory (BDI) scores and HbA1c, as an index of long-term glycemic control, was measured in samples of 30 patients with type 1 and 34 patients with type 2 diabetes. RESULTS: Groups of patients with type 1 and type 2 diabetes did not differ in mean BDI score or HbA1c level. Correlation analysis revealed a significant positive relationship between BDI scores and HbA1c in the type 1 group (r = .44, p < .02) but not in the type 2 group (r = -0.06, p > .05). This relationship was evident throughout the entire range of BDI scores and was not restricted to scores indicative of clinical depression. Patients with type 1 diabetes who had higher HbA1c and BDI scores reported a lower frequency of home blood glucose monitoring. CONCLUSIONS: Variations in depressive mood, below the level of clinical depression, are associated with meaningful differences in glycemic control in type 1 but not type 2 diabetes. Preliminary data analysis suggests that this effect may be mediated, at least in part, by decreased self-care behaviors in patients with more depressed mood.

Adult↗

PubMedDate not supplied

Glycemic control in diabetic patients served by community health centers.

The Community Health Center Network measured the prevalence of glycemic control in diabetic patients at 7 community health centers as part of its clinical quality improvement program. A cross-sectional survey was carried out in a random sample of 1817 diabetic patients having 1 or more encounters from October 1, 2000 to September 30, 2001. Computerized laboratory results for hemoglobin A1c (HbA1c) tests were available for half the sample. Manual review of medical charts was carried out for the rest. The proportion of diabetic patients with 1 or more HbA1c tests in the measurement year was 91% (CI95%: 90-93%) and poor glycemic control (HbA1c > 9%) occurred in 27% (CIM%: 25-30%). The mean of the most recent test was 7.8%. The frequency of testing varied significantly by clinic from 79% to 94% and increased with the number of encounters. Poor glycemic control also varied significantly by clinic (17-48%) and was significantly better in females and older patients. Measures of glycemic control were not associated with ethnicity or insurance status in multivariate analyses. A high proportion of diabetic patients received appropriate care, and this care was not associated with ethnicity or insurance status. The data warehouse was an essential tool for the clinical quality improvement program.

Adolescent↗

PubMedDate not supplied

Combination therapy with insulin and oral agents: optimizing glycemic control in patients with type 2 diabetes mellitus.

The United Kingdom Prospective Diabetes Study (UKPDS) showed that tight glycemic control with any of several therapeutic regimens has the potential to significantly reduce the risk for long-term microvascular complications of type 2 diabetes. An important question that remains to be answered is what is the best approach to optimizing glycemic control in patients with this disease. This article reviews results of studies in which insulin was used alone or in combination with oral antidiabetic agents for treatment of patients with type 2 diabetes. Analysis of comparative studies (13 in insulin-naive and 26 in previously insulin-treated patients) showed that combination therapy involving one to two insulin injections per day plus oral therapy is usually more effective than insulin monotherapy for achieving and maintaining glycemic control. Combination treatment for type 2 diabetes can be significantly improved by newly developed preparations that lack the major limitations of older products. Once-daily administration of isophane insulin (NPH insulin) is limited by a 15-18-h duration of action and a peak effect that occurs about 6 h after injection. Insulin glargine, a new insulin analogue developed using recombinant DNA technology, has a flat pharmacodynamic profile and a 24-h duration of action. Results from a recent comparative study indicate that insulin glargine plus oral therapy may provide better post-dinner glucose control as well as less symptomatic and nocturnal hypoglycemia than oral therapy combined with NPH insulin. The studies reviewed in the present article support the conclusion that combination therapy with insulin glargine combined with one or more oral antidiabetic agents may be the treatment of choice for achieving glycemic control in patients with type 2 diabetes.

Administration, Oral↗

PubMed2004

The factors affecting glycemic control in Japanese adolescents with type 2 diabetes mellitus.

The factors affecting glycemic control were examined using HbA(1C) as an index in a total of 22 patients with type 2 diabetes mellitus whose ages at onset were less than 18 years old. As a result, the presence or absence of the following cases were considered possible factors for significant exacerbation of glycemic control: diabetic microangiopathy; school phobia or nonworking situation; drug therapy; use of more than two kinds of oral hypoglycemic agents (OHAs) or insulin for the drug therapy cases. No improvement in glycemic control could be achieved even by increasing the number of OHAs for co-administration or by insulin use unless dietary/exercise therapy, a basic therapeutic option, was adequately performed.

Adolescent↗

PubMed2000

Depression and poor glycemic control: a meta-analytic review of the literature.

OBJECTIVE: Depression is common among patients with diabetes, but its relationship to glycemic control has not been systematically reviewed. Our objective was to determine whether depression is associated with poor glycemic control. RESEARCH DESIGN AND METHODS: Medline and PsycINFO databases and published reference lists were used to identify studies that measured the association of depression with glycemic control. Meta-analytic procedures were used to convert the findings to a common metric, calculate effect sizes (ESs), and statistically analyze the collective data. RESULTS: A total of 24 studies satisfied the inclusion and exclusion criteria for the meta-analysis. Depression was significantly associated with hyperglycemia (Z = 5.4, P < 0.0001). The standardized ES was in the small-to-moderate range (0.17) and was consistent, as the 95% CI was narrow (0.13-0.21). The ES was similar in studies of either type 1 or type 2 diabetes (ES 0.19 vs. 0.16) and larger when standardized interviews and diagnostic criteria rather than self-report questionnaires were used to assess depression (ES 0.28 vs. 0.15). CONCLUSIONS: Depression is associated with hyperglycemia in patients with type 1 or type 2 diabetes. Additional studies are needed to establish the directional nature of this relationship and to determine the effects of depression treatment on glycemic control and the long-term course of diabetes.

Adult↗

PubMed2000

Pathways from emotional adjustment to glycemic control in youths with diabetes in Hong Kong.

OBJECTIVE: To examine factors that influence emotional adjustment, adherence to diabetic care, and glycemic control in Hong Kong youths with insulin-dependent diabetes mellitus (IDDM). METHODS: Seventy youths, their mothers, and matched controls provided information on health beliefs, authoritarian parenting style, parent-child conflict, emotional adjustment, and adherence to medical regimen. Glycosylated hemoglobin levels were obtained to measure glycemic control. RESULTS: Predictors explained 34% of the variance in emotional adjustment and 39% of the variance in glycemic control. The data supported a pathway from emotional adjustment to self-efficacy to adherence behaviors to glycemic control. In contrast to Western culture and consistent with prediction, parenting style did not associate with negative outcomes, and even relatively low levels of parent-child conflict correlated negatively with emotional adjustment in this culture. CONCLUSIONS: Management of conflict and self-efficacy enhancing interactions are suggested interventions to enhance adherence to diabetic care in Hong Kong youths with IDDM.

Adaptation, Psychological↗

PubMed1998

The effects of metformin on glycemic control and serum lipids in insulin-treated NIDDM patients with suboptimal metabolic control.

OBJECTIVE: To test the hypothesis that metformin therapy, given as an adjunct to insulin therapy, improves metabolic control in insulin-treated NIDDM patients with suboptimal glycemic control. RESEARCH DESIGN AND METHODS: A total of 33 subjects with insulin-treated NIDDM were investigated; all had commenced insulin after secondary failure of antihyperglycemic agents. Two randomized double-blind placebo-controlled crossover studies were run. In study 1 (n = 19), insulin-treated subjects with suboptimal glycemic control received 12 weeks of metformin 1 g b.i.d. and 12 weeks of placebo. In study 2 (n = 14), subjects already established on adjunctive metformin/insulin therapy stopped the metformin component and received 12 weeks of metformin at their baseline dosage (range 1-2.5 g) and 12 weeks of equivalent placebo. Fasting plasma glucose, HbA1c, and serum lipids were measured at baseline and midway through and at the end of each treatment phase. The effect of 12 weeks of metformin treatment was compared with the effect of 12 weeks of placebo in each study and in both studies combined. RESULTS: In study 1, metformin treatment was associated with significant improvements in fasting plasma glucose (mean 12-week difference from placebo [95% CI]: 5.8 mmol/l [3.5-8.1], P < 0.001) and HbA1c (1.6% [0.9-2.4], P < 0.001). In study 2, metformin treatment was associated with significantly lower fasting plasma glucose (5.3 mmol/l [0.6-9.9], P = 0.029) and lower HbA1c (2.4% [1.0-3.8], P = 0.003) compared with those for placebo. Study 2 also showed metformin treatment to be associated with significantly lower total cholesterol than that for placebo (1.0 mmol/l [0.1-1.9], P = 0.032) and lower LDL cholesterol (1.0 mmol/l [0.1-1.9], P = 0.028). This significant difference in serum lipids seen in study 2 was not seen in study 1, but was present when both sets of data were combined (n = 33, mean total cholesterol difference at 12 weeks [95% CI]: 0.6 mmol/l [0.1-1.1], P = 0.015). Metformin had no significant effect on triglyceride, HDL cholesterol, weight, or blood pressure. Two subjects on metformin withdrew because of side effects. CONCLUSIONS: Metformin, when given as adjunctive therapy, was well tolerated and improved glycemic control and lipid concentrations in patients with insulin-treated NIDDM whose diabetes was poorly controlled. These improvements could be maintained over the long term.

Aged↗