Coefficient of failure: a methodology for examining longitudinal beta-cell function in Type 2 diabetes

Mode of treatments and achievement of treatment targets among type 2 diabetes patients with different comorbidities - a register-based retrospective cohort study in Finland

AIMS

Type 2 diabetes (T2D) is a progressive disease often associated with comorbidities that complicate the management of T2D and affect the achievement of treatment targets. However, adherence to guidelines and individualized treatments can potentially improve treatment outcomes. This study assessed the association between different glucose lowering and lipid lowering medication lines and the achievement of treatment targets with different comorbidities among a T2D cohort in North Karelia, Finland (2011-12 to 2015-16).

METHODS

The data on all diagnosed T2D patients (n = 10,190) in North Karelia were collated retrospectively from regional electronic health records (EHRs). Analyses were performed considering the age, sex, and comorbidities such as cardiovascular diseases (CVD) and any mental disorders (AMD). We analyzed the trends in using glucose lowering and lipid lowering medications and the effect of changes in medication on the achievement of treatment targets among different patient groups.

RESULTS

Metformin was the most common treatment in all patient groups. The use of only metformin declined and the use of metformin and/or other non-insulin medications increased during the follow-up. A Combination of insulin and non-insulin medication was mostly used by T2D patients with both cardiovascular diseases and mental disorders (T2D + CVD + AMD), and the use of insulin increased among this group in follow-up. Achievement of the glucose treatment target deteriorated even after the intensification of medication among all patient groups during the follow-up. A considerably higher number of patients with T2D + AMD and T2D + CVD + AMD did not use lipid lowering medication when compared to the T2D + CVD patients both at baseline and follow-up. However, the achievement of the LDL treatment target improved during the follow-up.

CONCLUSION

Achievement of the glucose target deteriorated even after the intensification of treatment, and especially among patients with multiple diseases. Many T2D patients with AMD and CVD remained without lipid lowering medication, which needs further attention.

Pathophysiology, phenotypes and management of type 2 diabetes mellitus in Indian and Chinese populations

Nearly half of all adults with type 2 diabetes mellitus (T2DM) live in India and China. These populations have an underlying predisposition to deficient insulin secretion, which has a key role in the pathogenesis of T2DM. Indian and Chinese people might be more susceptible to hepatic or skeletal muscle insulin resistance, respectively, than other populations, resulting in specific forms of insulin deficiency. Cluster-based phenotypic analyses demonstrate a higher frequency of severe insulin-deficient diabetes mellitus and younger ages at diagnosis, lower β-cell function, lower insulin resistance and lower BMI among Indian and Chinese people compared with European people. Individuals diagnosed earliest in life have the most aggressive course of disease and the highest risk of complications. These characteristics might contribute to distinctive responses to glucose-lowering medications. Incretin-based agents are particularly effective for lowering glucose levels in these populations; they enhance incretin-augmented insulin secretion and suppress glucagon secretion. Sodium-glucose cotransporter 2 inhibitors might also lower blood levels of glucose especially effectively among Asian people, while α-glucosidase inhibitors are better tolerated in east Asian populations versus other populations. Further research is needed to better characterize and address the pathophysiology and phenotypes of T2DM in Indian and Chinese populations, and to further develop individualized treatment strategies.

Durability of glycaemic control in type 2 diabetes: A systematic review and meta-analysis for its association with body weight changes

AIMS

To analyse quantitatively the association between the durability of glycaemic control and body weight changes during treatment.

MATERIALS AND METHODS

This study adhered to an appropriate methodology according to Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Studies with follow-ups >12 months, and final and intermediate assessments of haemoglobin A1c (HbA1c) and body weight were included. Four outcomes assessing therapeutic durability were extracted and synthesized using Stata statistical software, including changes in HbA1c, goal-achievement rate, failure rate and coefficient of failure (CoF).

RESULTS

After 8.9 months of treatment, HbA1c levels declined from 8.03% [95% confidence interval (CI), 7.91-8.15; I² = 99.2%] to 7.15% (95% CI, 7.02-7.27; I² = 99.4%) and then gradually increased up to 7.72% (95% CI, 7.50-7.94; I² = 99.0%) 5 years later. The goal-achievement rate decreased from 54.8% (after 1 year of treatment) to 19.4% 5 years later. The CoF was 0.123 ± 0.022%/year (P < .001). After stratification, the CoFs were 0.224 ± 0.025%/year (P < .001) for weight gain, 0.137 ± 0.034%/year (P < .001) for neutral weight and -0.024 ± 0.032%/year (P = .450) for weight loss. After stratification by treatment approaches, the CoFs were 0.45%/year for insulin, 0.43%/year for sulphonylurea, 0.34%/year for thiazolidinediones, 0.29%/year for metformin, 0.16% for glucagon-like polypeptide-1 receptor agonists, 0.12% for surgery, -0.03% for sodium-glucose cotransporter-2 inhibitors and -0.21% for dipeptidyl peptidase-IV inhibitors.

CONCLUSION

Modest weight loss with a goal of 2-3% of body weight should be recommended to improve therapeutic durability and prevent beta-cell deterioration.

Age at diagnosis, glycemic trajectories, and responses to oral glucose-lowering drugs in type 2 diabetes in Hong Kong: A population-based observational study

BACKGROUND

Lifetime glycemic exposure and its relationship with age at diagnosis in type 2 diabetes (T2D) are unknown. Pharmacologic glycemic management strategies for young-onset T2D (age at diagnosis <40 years) are poorly defined. We studied how age at diagnosis affects glycemic exposure, glycemic deterioration, and responses to oral glucose-lowering drugs (OGLDs).

METHODS AND FINDINGS

In a population-based cohort (n = 328,199; 47.2% women; mean age 34.6 and 59.3 years, respectively, for young-onset and usual-onset [age at diagnosis ≥40 years] T2D; 2002-2016), we used linear mixed-effects models to estimate the association between age at diagnosis and A1C slope (glycemic deterioration) and tested for an interaction between age at diagnosis and responses to various combinations of OGLDs during the first decade after diagnosis. In a register-based cohort (n = 21,016; 47.1% women; mean age 43.8 and 58.9 years, respectively, for young- and usual-onset T2D; 2000-2015), we estimated the glycemic exposure from diagnosis until age 75 years. People with young-onset T2D had a higher mean A1C (8.0% [standard deviation 0.15%]) versus usual-onset T2D (7.6% [0.03%]) throughout the life span (p < 0.001). The cumulative glycemic exposure was >3 times higher for young-onset versus usual-onset T2D (41.0 [95% confidence interval 39.1-42.8] versus 12.1 [11.8-12.3] A1C-years [1 A1C-year = 1 year with 8% average A1C]). Younger age at diagnosis was associated with faster glycemic deterioration (A1C slope over time +0.08% [0.078-0.084%] per year for age at diagnosis 20 years versus +0.02% [0.016-0.018%] per year for age at diagnosis 50 years; p-value for interaction <0.001). Age at diagnosis ≥60 years was associated with glycemic improvement (-0.004% [-0.005 to -0.004%] and -0.02% [-0.027 to -0.0244%] per year for ages 60 and 70 years at diagnosis, respectively; p-value for interaction <0.001). Responses to OGLDs differed by age at diagnosis (p-value for interaction <0.001). Those with young-onset T2D had smaller A1C decrements for metformin-based combinations versus usual-onset T2D (metformin alone: young-onset -0.15% [-0.105 to -0.080%], usual-onset -0.17% [-0.179 to -0.169%]; metformin, sulfonylurea, and dipeptidyl peptidase-4 inhibitor: young-onset -0.44% [-0.476 to -0.405%], usual-onset -0.48% [-0.498 to -0.459%]; metformin and α-glucosidase inhibitor: young-onset -0.40% [-0.660 to -0.144%], usual-onset -0.25% [-0.420 to -0.077%]) but greater responses to other combinations containing sulfonylureas (sulfonylurea alone: young-onset -0.08% [-0.099 to -0.065%], usual-onset +0.06% [+0.059 to +0.072%]; sulfonylurea and α-glucosidase inhibitor: young-onset -0.10% [-0.266 to 0.064%], usual-onset: 0.25% [+0.196% to +0.312%]). Limitations include possible residual confounding and unknown generalizability outside Hong Kong.

CONCLUSIONS

In this study, we observed excess glycemic exposure and rapid glycemic deterioration in young-onset T2D, indicating that improved treatment strategies are needed in this setting. The differential responses to OGLDs between young- and usual-onset T2D suggest that better disease classification could guide personalized therapy.

The impact of phenotype, ethnicity and genotype on progression of type 2 diabetes mellitus

AIM

To conduct a comprehensive review of studies of glycaemic deterioration in type 2 diabetes and identify the major factors influencing progression.

METHODS

We conducted a systematic literature search with terms linked to type 2 diabetes progression. All the included studies were summarized based upon the factors associated with diabetes progression and how the diabetes progression was defined.

RESULTS

Our search yielded 2785 articles; based on title, abstract and full-text review, we included 61 studies in the review. We identified seven criteria for diabetes progression: 'Initiation of insulin', 'Initiation of oral antidiabetic drug', 'treatment intensification', 'antidiabetic therapy failure', 'glycaemic deterioration', 'decline in beta-cell function' and 'change in insulin dose'. The determinants of diabetes progression were grouped into phenotypic, ethnicity and genotypic factors. Younger age, poorer glycaemia and higher body mass index at diabetes diagnosis were the main phenotypic factors associated with rapid progression. The effect of genotypic factors on progression was assessed using polygenic risk scores (PRS); a PRS constructed from the genetic variants linked to insulin resistance was associated with rapid glycaemic deterioration. The evidence of impact of ethnicity on progression was inconclusive due to the small number of multi-ethnic studies.

CONCLUSION

We have identified the major determinants of diabetes progression-younger age, higher BMI, higher HbA1c and genetic insulin resistance. The impact of ethnicity is uncertain; there is a clear need for more large-scale studies of diabetes progression in different ethnic groups.

Durability of glycaemic control with dapagliflozin, an SGLT2 inhibitor, compared with saxagliptin, a DPP4 inhibitor, in patients with inadequately controlled type 2 diabetes

Dapagliflozin is associated with greater reductions in HbA1c and weight than saxagliptin in management of type 2 diabetes mellitus (T2DM). The present post hoc analyses compared the durability of these effects over short- and long-term follow-up in patients with T2DM who were inadequately controlled with metformin (≥1500 mg/day) and who were receiving either dapagliflozin (10 mg/day) or saxagliptin (5 mg/day). Failure of glycaemiccontrol was assessed using the slope of the change in HbA1c from baseline-over-time regression line (coefficient of failure [CoF]). CoF was compared directly (dapagliflozin vs saxagliptin) over the short term (NCT01606007, 24 weeks) and indirectly (placebo-adjusted) over the long term (NCT00528879 and NCT00121667, 102 weeks). A low CoF value indicated greater durability. CoF was lower for dapagliflozin versus saxagliptin over 18-24 weeks (-1.38%/year; 95% CI, -2.41 to -0.35; P = .009) and 20-102 weeks (-0.37%/year; 95% CI, -0.73 to -0.02; P = .04). Fewer dapagliflozin-treated patients versus saxagliptin-treated patients required rescue medication or discontinued the study because of failure to achieve glycaemic control at 24 weeks (3.4% vs 9.4%; P = .0191). In patients with T2DM who were inadequately controlled with metformin, dapagliflozin was associated with greater durability of glycaemic control than saxagliptin over 18-24 and 20-102 weeks.

Defining Disease Progression and Drug Durability in Type 2 Diabetes Mellitus

This communication shares insights into the definition of disease progression and drug durability in type 2 diabetes. Disease progression may be defined as gradual worsening of beta-cell function, clinically observed as an increase in drug dosage, drug frequency or number of glucose lowering drugs needed to maintain HbA1c control; and/or a ≥0.5% rise in HbA1c, unexplained by acute, modifiable factors, while using the same drug regimen; and/or as the occurrence or worsening of cardiovascular or microvascular complications, in spite of standard care, over a pre-specified time period. Durability of a drug or a drug combination may be defined as its ability to postpone or delay progression of disease, in a safe and well tolerated manner. Thus, all drugs that are able to prevent disease progression (i.e., postpone loss of glycaemic control, need for intensification of therapy or onset or worsening of complications) may be termed ‘durable’.

Reflections on the sulphonylurea story: A drug class at risk of extinction or a drug class worth reviving?

The role of sulphonylureas (SUs) in modern clinical practice poses ongoing clinical debate. With the advent of newer agents in diabetes management, there is an increasing shift away from the prescribing of SUs, but not necessarily to more effective agents. This review provides a different perspective on the debate, reflecting in depth upon the physiology of SUs, drawing on insights gained from monogenic diabetes to highlight the potential benefit of lower doses of SUs, and the probable benefit of gliclazide over most other, if not all SUs, in terms of sulphonylurea failure and cardiovascular outcomes.

Maintenance of good glycaemic control is challenging - A cohort study of type 2 diabetes patient in North Karelia, Finland

AIMS

This study assessed type 2 diabetes treatment outcomes and process indicators using a comprehensive type 2 diabetes patient cohort in North Karelia, Finland, from 2011 to 2016.

METHODS

Data from all diagnosed type 2 diabetes patients (n = 8429) living in North Karelia were collated retrospectively from regional electronic patient records. We assessed whether HbA1c and low-density lipoprotein (LDL) were measured and managed as recommended.

RESULTS

The HbA1c measurement rate improved (78% vs 89%) during 2011-2012 and 2015-2016, but a gradual deterioration in glycaemic control (HbA1c < 7.0% or 53 mmol/mol) was observed among both females (75% vs 67%) and males (72% vs 64%). The LDL measurement rate initially improved from the baseline. LDL control (<2.5 mmol/L) improved among both females (52% vs 59%) and males (58% vs 66%). A gender difference was observed in the achievement of the treatment target for LDL, with females showing worse control.

CONCLUSIONS

Low-density lipoprotein (LDL) control in type 2 diabetes patients has improved, but the existence of gender disparities needs further attention. Maintaining appropriate HbA1c control among type 2 diabetes patients over time appears to be difficult. Active follow-up and tailored treatment have the potential to improve the quality of care. Electronic patient records could be more efficiently used to improve the quality of care and to support decision-making.

Rates of glycaemic deterioration in a real-world population with type 2 diabetes

AIMS/HYPOTHESIS

There is considerable variability in how diabetes progresses after diagnosis. Progression modelling has largely focused on 'time to failure' methods, yet determining a 'coefficient of failure' has many advantages. We derived a rate of glycaemic deterioration in type 2 diabetes, using a large real-world cohort, and aimed to investigate the clinical, biochemical, pharmacological and immunological variables associated with fast and slow rates of glycaemic deterioration.

METHODS

An observational cohort study was performed using the electronic medical records from participants in the Genetics of Diabetes Audit and Research in Tayside Study (GoDARTS). A model was derived based on an individual's observed HbA_1c measures from the first eligible HbA_1c after the diagnosis of diabetes through to the study end (defined as insulin initiation, death, leaving the area or end of follow-up). Each HbA_1c measure was time-dependently adjusted for the effects of non-insulin glucose-lowering drugs, changes in BMI and corticosteroid use. GAD antibody (GADA) positivity was defined as GAD titres above the 97.5th centile of the population distribution.

RESULTS

The mean (95% CI) glycaemic deterioration for type 2 diabetes and GADA-positive individuals was 1.4 (1.3, 1.4) and 2.8 (2.4, 3.3) mmol/mol HbA_1c per year, respectively. A younger age of diagnosis, lower HDL-cholesterol concentration, higher BMI and earlier calendar year of diabetes diagnosis were independently associated with higher rates of glycaemic deterioration in individuals with type 2 diabetes. The rate of deterioration in those diagnosed at over 70 years of age was very low, with 66% having a rate of deterioration of less than 1.1 mmol/mol HbA_1c per year, and only 1.5% progressing more rapidly than 4.4 mmol/mol HbA_1c per year.

CONCLUSIONS/INTERPRETATION

We have developed a novel approach for modelling the progression of diabetes in observational data across multiple drug combinations. This approach highlights how glycaemic deterioration in those diagnosed at over 70 years of age is minimal, supporting a stratified approach to diabetes management.

Review of methods for measuring β-cell function: Design considerations from the Restoring Insulin Secretion (RISE) Consortium

The Restoring Insulin Secretion (RISE) study was initiated to evaluate interventions to slow or reverse the progression of β-cell failure in type 2 diabetes (T2D). To design the RISE study, we undertook an evaluation of methods for measurement of β-cell function and changes in β-cell function in response to interventions. In the present paper, we review approaches for measurement of β-cell function, focusing on methodologic and feasibility considerations. Methodologic considerations included: (1) the utility of each technique for evaluating key aspects of β-cell function (first- and second-phase insulin secretion, maximum insulin secretion, glucose sensitivity, incretin effects) and (2) tactics for incorporating a measurement of insulin sensitivity in order to adjust insulin secretion measures for insulin sensitivity appropriately. Of particular concern were the capacity to measure β-cell function accurately in those with poor function, as is seen in established T2D, and the capacity of each method for demonstrating treatment-induced changes in β-cell function. Feasibility considerations included: staff burden, including time and required methodological expertise; participant burden, including time and number of study visits; and ease of standardizing methods across a multicentre consortium. After this evaluation, we selected a 2-day measurement procedure, combining a 3-hour 75-g oral glucose tolerance test and a 2-stage hyperglycaemic clamp procedure, augmented with arginine.

The effect of text message support on diabetes self-management in developing countries - A randomised trial

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Report of a randomised trial on an mHealth intervention in 3 low income countries.

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There was no additional effect of the text message self-management support.

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Coverage, routine care and disease progression interfere with the potential impact.

Objective

mHealth interventions have the potential to facilitate self-management. This TEXT4DSM study implemented a mobile phone intervention in existing diabetes programmes in three low- and middle-income countries (Democratic Republic of Congo, Cambodia, and the Philippines).

Research design and methods

Sub-studies with a similar randomised controlled trial design were conducted in three different countries. Each sub-study included 480 adults with diabetes. Subjects were randomised to receive either routine care or routine care plus text message self-management support. The primary outcome was the difference in the proportion of subjects with well-controlled diabetes after 2 years.

Results

Baseline and 2-year HbA1c measurements were available for 781 individuals. After 2 years, the proportion of subjects with controlled HbA1c was 2.8% higher in the intervention group than in the control group (difference not statistically significant). In the logistic regression model, the odds ratio for having controlled diabetes after the intervention was 1.1, after adjusting for baseline HbA1c level, sex, receiving insulin treatment, and participating in the routine programme. The HbA1c dynamics over time differed between programmes; the number of people with controlled diabetes tended to increase in DR Congo and decrease in Cambodia.

Conclusion

This study was the first to test the same mHealth intervention in different countries. The finding that text messages did not show an additional effect on diabetes control implied that expectations about mHealth should be cautious. The degree of coverage, the quality of the routine programme, and the progression of disease can interfere with the expected impact.

Trial registration: ISRCTN registry (86247213).

Glycaemic control and lipid concentrations in a cohort of people with diabetes over 7 years of follow-up: a regional audit of diabetes care in the UK

AIM

To determine changes in glycaemic control and lipids over time since the introduction of the Quality and Outcomes Framework.

METHODS

In adults with diabetes (Hampshire, UK), HbA1c and lipid measurements were retrieved from a regional National Health Service biochemical database in 2006 and 2013 and analysed using anova and logistic regression modelling.

RESULTS

In 2006, 8568 people with diabetes were identified. In 2013, 5815 had follow-up data, 1207 people were lost to follow-up and 1546 had died. At baseline, HbA1c concentrations were 62.1 ± 16.1, 64.7 ± 16.7 and 64.5 ± 17.6 mmol/mol for those with follow-up data, those lost to follow-up and those who died, respectively. The mean age was 60.2 ± 14.5, 57.6 ± 18.0 and 73.9 ± 10.5 years, respectively, for the three groups. Total cholesterol, HDL cholesterol and triglyceride concentrations were similar between groups. The mean HbA1c concentration for those with complete follow-up data was 62.1 ± 16.1 mmol/mol in 2006 and 61.7 ± 17.3 mmol/mol in 2013. Quality and Outcomes Framework targets for cholesterol (< 5 mmol/l) were achieved by 79% of people in 2006 and 83% in 2013 (P < 0.001). Baseline age and HbA1c were associated with death at follow-up: the odds ratio per year increase in baseline age was 1.10 (95% CI 1.09-1.10; P < 0.001) and per unit increase in HbA1c it was 1.02 (95% CI 1.02-1.03; P < 0.001).

CONCLUSIONS

Glycaemic control showed remarkable stability over 7 years of follow-up, despite increasing patient age and duration of diabetes. More patients achieved lipid targets in 2013 than in 2006. Although baseline HbA1c was a predictor of death at follow-up, baseline HbA1c differed little between survivors, non-survivors and those lost to follow-up.

Long-term glycaemic response and tolerability of dapagliflozin versus a sulphonylurea as add-on therapy to metformin in patients with type 2 diabetes: 4-year data

AIMS

To assess the long-term efficacy and tolerability of dapagliflozin versus glipizide as add-on to metformin in patients with inadequately controlled type 2 diabetes.

METHODS

The present study was an extension of an earlier randomized, double-blind, phase III study of dapagliflozin (n = 406) vs glipizide (n = 408) to 208 weeks (4 years). Patients continued to receive their assigned medication. No statistical treatment-group comparisons were calculated.

RESULTS

At 208 weeks, dapagliflozin compared with glipizide produced sustained reductions in glycated haemoglogin (HbA1c): -0.30% [95% confidence interval (CI), -0.51 to -0.09], in total body weight: -4.38 kg (95% CI -5.31 to -3.46) and in systolic blood pressure (SBP): -3.67 mmHg (95% CI -5.92 to -1.41). The HbA1c coefficient of failure was significantly lower for dapagliflozin than for glipizide: 0.19 (95% CI 0.12-0.25) versus 0.61 (95% CI 0.49-0.72, difference -0.42; p = 0.0001). Dapagliflozin was not associated with glomerular function deterioration, while this occurred more frequently in patients in the glipizide group. Fewer patients reported hypoglycaemia in the dapagliflozin compared with the glipizide group (5.4 vs 51.5%). Genital and urinary tract infections were more common with dapagliflozin than with glipizide, but their incidence decreased with time and all events responded well to antimicrobial treatment.

CONCLUSIONS

In patients completing 4 years of treatment, dapagliflozin was well tolerated and associated with sustained glycaemic efficacy and greater reductions in body weight and SBP versus glipizide.

Evaluation of the long-term durability and glycemic control of fasting plasma glucose and glycosylated hemoglobin for pioglitazone in Japanese patients with type 2 diabetes

BACKGROUND

This study applied a pharmacodynamic model-based approach to evaluate the long-term durability and glycemic control of pioglitazone in comparison with other oral glucose-lowering drugs in Japanese type 2 diabetes mellitus (T2DM) patients.

SUBJECTS AND METHODS

Japanese T2DM patients were enrolled in a prospective, randomized, open-label, blinded-end point study and received pioglitazone with or without other oral glucose-lowering drugs (excluding another thiazolidinedione [TZD]) (n=293) or oral glucose-lowering drugs excluding TZD (n=294). Treatment was adjusted to achieve glycosylated hemoglobin (HbA1c) <6.9%, and samples for fasting plasma glucose (FPG) and HbA1c were collected over 2.5-4 years. A simultaneous cascading indirect response model structure was applied to describe the time course of FPG and HbA1c. HbA1c levels were described using both an FPG-dependent and an FPG-independent function. To account for titration, drug effects for both treatment groups were implemented using a time-dependent Emax model.

RESULTS

Pioglitazone was superior in both time to maximum effect and the magnitude of reduction achieved in FPG and HbA1c. A greater reduction in median FPG (-21 mg/dL vs. -9 mg/dL) was observed with pioglitazone (P<0.05). Maximum drug effect for FPG was predicted to occur earlier (11 months) for pioglitazone than for the control group (14 months). The simulated additional reduction in FPG and HbA1c achieved with pioglitazone was predicted to be maintained beyond the currently observed study duration.

CONCLUSIONS

Pioglitazone was found to result in improved glycemic control and durability compared with control treatment. This model-based approach enabled the quantification of differences in FPG and HbA1c for both treatment groups and simulation to evaluate longer-term durability on FPG and HbA1c.

Durability of glycaemic efficacy over 2 years with dapagliflozin versus glipizide as add-on therapies in patients whose type 2 diabetes mellitus is inadequately controlled with metformin

AIMS

To assess the long-term glycaemic durability, safety and tolerability of dapagliflozin versus glipizide as add-on therapies in patients with type 2 diabetes inadequately controlled by metformin alone.

METHODS

This was a 52-week, randomised, double-blind study of dapagliflozin (n = 406) versus glipizide (n = 408), uptitrated over 18 weeks according to tolerability and glycaemic response to a maximum of 10 and 20 mg/day, respectively, as add-on therapies to metformin (≥ 1500 mg/day) with a 156-week double-blind extension period. Data over 104 weeks are reported here.

RESULTS

In total, 53.1% of patients completed 104 weeks of treatment. After the greater initial decrease (0-18 weeks) in glycated haemoglobin (HbA1c) with glipizide, the 18-104-week HbA1c coefficient of failure (CoF) was lower with dapagliflozin (0.13%/year) than with glipizide (0.59%/year), resulting in significant dapagliflozin versus glipizide differences of -0.46%/year (95% CI -0.60,-0.33; p = 0.0001) for CoF and -0.18%(-2.0 mmol/mol) [95% CI -0.33(-3.6),-0.03(-0.3); p = 0.021] for 104-week HbA1c. Dapagliflozin produced sustained reductions in weight and systolic blood pressure, whereas glipizide increased weight and systolic blood pressure, giving 104-week dapagliflozin versus glipizide differences of -5.1 kg (95% CI: -5.7,-4.4) and -3.9 mmHg (95% CI: -6.1,-1.7), respectively. Over 104 weeks, the hypoglycaemia rate was 10-fold lower with dapagliflozin than with glipizide (4.2 vs. 45.8%), whereas patient proportions with events suggestive of genital infection and of urinary tract infection (UTI) were greater with dapagliflozin (14.8 and 13.5%, respectively) than with glipizide (2.9 and 9.1%, respectively).

CONCLUSIONS

Over 2 years, compared with glipizide, dapagliflozin demonstrated greater glycaemic durability, sustained reductions in weight and systolic blood pressure and a low hypoglycaemia rate; however, genital infections and UTIs occurred more frequently.

Study to determine the durability of glycaemic control with early treatment with a vildagliptin-metformin combination regimen vs. standard-of-care metformin monotherapy-the VERIFY trial: a randomized double-blind trial

AIMS

Durability of good glycaemic control (HbA1c ) is of importance as it can be the foundation for delaying diabetic complications. It has been hypothesized that early initiation of treatment with the combination of oral anti-diabetes agents with complementary mechanisms of action can increase the durability of glycaemic control compared with metformin monotherapy followed by a stepwise addition of oral agents. Dipeptidyl peptidase-4 inhibitors are good candidates for early use as they are efficacious in combination with metformin, show weight neutrality and a low risk of hypoglycaemia. We aimed to test the hypothesis that early combined treatment of metformin and vildagliptin slows β-cell deterioration as measured by HbA1c .

METHODS

Approximately 2000 people with Type 2 diabetes mellitus who were drug-naive or who were treated with metformin for less than 1 month, and who have HbA1c of 48-58 mmol/mol (6.5-7.5%), will be randomized in a 1:1 ratio in VERIFY, a 5-year multinational, double-blind, parallel-group study designed to compare early initiation of a vildagliptin-metformin combination with standard-of-care initiation of metformin monotherapy, followed by the stepwise addition of vildagliptin when glycaemia deteriorates. Further deterioration will be treated with insulin. The primary analysis for treatment failure will be from a Cox proportional hazard regression model and the durability of glycaemic control will be evaluated by assessing treatment failure rate and the rate of loss in glycaemic control over time as co-primary endpoints.

SUMMARY

VERIFY is the first study to investigate the long-term clinical benefits of early combination treatment vs. the standard-of-care metformin monotherapy with a second agent added by threshold criteria.

A combined analysis of 48 type 2 diabetes genetic risk variants shows no discriminative value to predict time to first prescription of a glucose lowering drug in Danish patients with screen detected type 2 diabetes

OBJECTIVE

To investigate the genetic influence of 48 type 2 diabetes susceptibility variants on disease progression measured as risk of early prescription redemption of glucose lowering drugs in screen-detected patients with type 2 diabetes.

METHODS

We studied type 2 diabetes progression in 1,480 patients with screen-detected type 2 diabetes from the ADDITION-Denmark study using information of redeemed prescriptions from the Register of Medicinal Products Statistics from 2001-2009 in Denmark. Patients were cluster randomized by general practitioners, who were randomized to treat type 2 diabetes according to either a conventional or a multifactorial intensive treatment algorithm. We investigated the genetic influence on diabetes progression by constructing a genetic risk score (GRS) of all 48 validated type 2 diabetes susceptibility variants, a GRS of 11 variants linked to β-cell function and a GRS of 3 variants linked to insulin sensitivity and assessed the association between number of risk alleles and time from diagnosis until first redeemed prescription of either any glucose lowering drug or an insulin drug.

RESULTS

The GRS linked to insulin sensitivity only nominally increased the risk of an early prescription redemption with an insulin drug by 39% (HR [95% C.I.] = 1.39 [1.09-1.77], p = 0.009] in patients randomized to the intensive treatment group. Furthermore, the strongest univariate predictors of diabetes progression for the intensive treatment group (measured as time to first insulin) were younger age (HR [95% C.I.] = 0.96 [0.93-0.99]), increased BMI (1.05 [1.01-1.09]), increased HbA1c (1.50 [1.36-.66]), increased TG (1.24 [1.11-1.39]) and reduced fasting serum HDL (0.37 [0.17-0.80]) at baseline. Similar results were obtained for the conventional treatment group.

CONCLUSION

Higher levels of HbA1c, fasting circulating levels of triglyceride, lower HDL, larger BMI and younger age are significant determinants of early pharmacological intervention in type 2 diabetes. However, known common type 2 diabetes-associated gene variants do not appear to significantly affect disease progression.

Twenty-year trend of increasing obesity in young patients with poorly controlled type 2 diabetes at first diagnosis in urban Japan

Aims/Introduction

To investigate trends over the past 20 years for the prevalence of obesity and glycemic control in association with a patient's first hospital visit for type 2 diabetes mellitus.

Materials and Methods

This was a historical, cross‐sectional, time‐series, single‐center study carried out at Marunouchi Hospital. Data from type 2 diabetic patients who were never treated until their first hospital visit were analyzed for the following periods: 1986–1987 (group A, n = 453), 1996–1997 (group B, n = 547) and 2006–2008 (group C, n = 443). Data on each patient's body mass index (BMI), age, untreated duration and glycated hemoglobin levels were also collected.

Results

Obesity in younger patients (below age 40 years and ages 40–49 years in group C) with poor glycemic control increased over time. Patients with a BMI of <21.0 kg/m² or ≥23.0 kg/m² showed worse glycemic control than those with a BMI of 21.0–23.0 kg/m² in group C. Younger patients had worse glycemic control and shorter untreated durations in group C. A BMI ≥23.0 kg/m² was an independent risk factor for glycated hemoglobin levels ≥8.4% in group C, even after correction for sex, age, untreated duration and symptoms.

Conclusions

In recent years, glycemic control has worsened in young, obese patients in urban Japan. Obesity is rapidly increasing in younger patients, and patients with a BMI ≥23.0 kg/m² might be candidates for diabetes screening. This trial was registered with the University Medical Information Network Clinical Trials Registry (no. UMIN000005725).

LX4211 increases serum glucagon-like peptide 1 and peptide YY levels by reducing sodium/glucose cotransporter 1 (SGLT1)-mediated absorption of intestinal glucose

LX4211 [(2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(methylthio)tetrahydro-2H-pyran-3,4,5-triol], a dual sodium/glucose cotransporter 1 (SGLT1) and SGLT2 inhibitor, is thought to decrease both renal glucose reabsorption by inhibiting SGLT2 and intestinal glucose absorption by inhibiting SGLT1. In clinical trials in patients with type 2 diabetes mellitus (T2DM), LX4211 treatment improved glycemic control while increasing circulating levels of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY). To better understand how LX4211 increases GLP-1 and PYY levels, we challenged SGLT1 knockout (-/-) mice, SGLT2-/- mice, and LX4211-treated mice with oral glucose. LX4211-treated mice and SGLT1-/- mice had increased levels of plasma GLP-1, plasma PYY, and intestinal glucose during the 6 hours after a glucose-containing meal, as reflected by area under the curve (AUC) values, whereas SGLT2-/- mice showed no response. LX4211-treated mice and SGLT1-/- mice also had increased GLP-1 AUC values, decreased glucose-dependent insulinotropic polypeptide (GIP) AUC values, and decreased blood glucose excursions during the 6 hours after a challenge with oral glucose alone. However, GLP-1 and GIP levels were not increased in LX4211-treated mice and were decreased in SGLT1-/- mice, 5 minutes after oral glucose, consistent with studies linking decreased intestinal SGLT1 activity with reduced GLP-1 and GIP levels 5 minutes after oral glucose. These data suggest that LX4211 reduces intestinal glucose absorption by inhibiting SGLT1, resulting in net increases in GLP-1 and PYY release and decreases in GIP release and blood glucose excursions. The ability to inhibit both intestinal SGLT1 and renal SGLT2 provides LX4211 with a novel dual mechanism of action for improving glycemic control in patients with T2DM.

Effects of LX4211, a dual SGLT1/SGLT2 inhibitor, plus sitagliptin on postprandial active GLP-1 and glycemic control in type 2 diabetes

BACKGROUND

Combination therapy is required to provide adequate glycemic control in many patients with type 2 diabetes mellitus (T2DM). Because sodium-dependent glucose transporter (SGLT)-1 inhibition results in an increased release of glucagon-like peptide (GLP)-1, and because dipeptidyl peptidase (DPP)-4 inhibitors prevent its inactivation, the 2 mechanisms together provide an intriguing potential combination therapy.

OBJECTIVES

This combination was explored in preclinical models and then tested in patients with T2DM to compare the effects of single-dose LX4211 400 mg and sitagliptin 100 mg, administered as monotherapy or in combination, on GLP-1, peptide tyrosine tyrosine (PYY), gastric inhibitory peptide (GIP), glucose, and insulin.

METHODS

Preclinical: Obese male C57BL6J mice were assigned to 1 of 4 treatment groups: LX4211 60 mg/kg, sitagliptin 30 mg/kg, LX4211 + sitagliptin, or inactive vehicle. Clinical: This 3-treatment, 3-crossover, randomized, open-label study was conducted at a single center. Patients on metformin monotherapy were washed out from metformin and were randomly assigned to receive sequences of single-dose LX4211, sitagliptin, or the combination. In both studies, blood was collected for the analysis of pharmacodynamic variables (GLP-1, PYY, GIP, glucose, and insulin). In the clinical study, urine was collected to assess urinary glucose excretion.

RESULTS

Preclinical: 120 mice were treated and assessed (5/time point/treatment group). With repeat daily dosing, the combination was associated with apparently synergistic increases in active GLP-1 relative to monotherapy with either agent; this finding was supported by findings from an additional 14-day repeated-dose experiment. Clinical: 18 patients were enrolled and treated (mean age, 49 years; 56% male; 89% white). The LX4211 + sitagliptin combination was associated with significantly increased active GLP-1, total GLP-1, and total PYY; with a significant reduction in total GIP; and with a significantly improved blood glucose level, with less insulin, compared with sitagliptin monotherapy. LX4211 was associated with a significant increase in total GLP-1 and PYY and a reduced total GIP, likely due to a reduction in SGLT1-mediated intestinal glucose absorption, whereas sitagliptin was associated with suppression of all 3 peptides relative to baseline. All treatments were well tolerated, with no evidence of diarrhea with LX4211 treatment.

CONCLUSIONS

The findings from the preclinical studies suggest that the LX4211 + sitagliptin combination produced synergistic increases in active GLP-1 after a meal challenge containing glucose. These initial clinical results also suggest that a LX4211 + DPP-4 inhibitor combination may provide an option in patients with T2DM. The potential long-term clinical benefits of such combination treatment need to be confirmed in large clinical trials. ClinicalTrials.gov identifier: NCT01441232.

LX4211, a dual SGLT1/SGLT2 inhibitor, improved glycemic control in patients with type 2 diabetes in a randomized, placebo-controlled trial

Thirty-six patients with type 2 diabetes mellitus (T2DM) were randomized 1:1:1 to receive a once-daily oral dose of placebo or 150 or 300 mg of the dual SGLT1/SGLT2 inhibitor LX4211 for 28 days. Relative to placebo, LX4211 enhanced urinary glucose excretion by inhibiting SGLT2-mediated renal glucose reabsorption; markedly and significantly improved multiple measures of glycemic control, including fasting plasma glucose, oral glucose tolerance, and HbA(1c); and significantly lowered serum triglycerides. LX4211 also mediated trends for lower weight, lower blood pressure, and higher glucagon-like peptide-1 levels. In a follow-up single-dose study in 12 patients with T2DM, LX4211 (300 mg) significantly increased glucagon-like peptide-1 and peptide YY levels relative to pretreatment values, probably by delaying SGLT1-mediated intestinal glucose absorption. In both studies, LX4211 was well tolerated without evidence of increased gastrointestinal side effects. These data support further study of LX4211-mediated dual SGLT1/SGLT2 inhibition as a novel mechanism of action in the treatment of T2DM.

Vildagliptin add-on to metformin produces similar efficacy and reduced hypoglycaemic risk compared with glimepiride, with no weight gain: results from a 2-year study

AIM

To show that vildagliptin added to metformin is non-inferior to glimepiride in reducing HbA1c levels from baseline over 2 years.

METHODS

A randomized, double-blind, active-comparator study of patients with type 2 diabetes mellitus inadequately controlled (HbA1c 6.5-8.5%) by metformin monotherapy. Patients received vildagliptin (50 mg twice daily) or glimepiride (up to 6 mg/day) added to metformin.

RESULTS

In all, 3118 patients were randomized (vildagliptin, n = 1562; glimepiride, n = 1556). From similar baseline values (7.3%), after 2 years adjusted mean (s.e.) change in HbA1c was comparable between vildagliptin and glimepiride treatment: -0.1% (0.0%) and -0.1% (0.0%), respectively. The primary objective of non-inferiority was met. A similar proportion of patients reached HbA1c <7% (36.9 and 38.3%, respectively), but with vildagliptin more patients reached this target without hypoglycaemia (36.0% vs. 28.8%; p = 0.004). The initial response (IR) was sustained for a mean (s.d.) of 309 (244) days with vildagliptin versus 270 (223) days for glimepiride (p < 0.001) (IR = nadir HbA1c where change from baseline > or =0.5% or HbA1c < or =6.5% within the first six months of treatment. After IR was detected, sustained response = time between nadir and an increase of >0.3% above IR). Independent of disease duration, age was a predictor of effect sustainability. Fewer patients experienced hypoglycaemia with vildagliptin (2.3% vs. 18.2% with glimepiride) with a 14-fold difference in the number of hypoglycaemic events (59 vs. 838). Vildagliptin had a beneficial effect on body weight [mean (s.e.) change from baseline -0.3 (0.1) kg; between-group difference -1.5 kg; p < 0.001]. Overall, both treatments were well tolerated and displayed similar safety profiles.

CONCLUSIONS

Vildagliptin add-on has similar efficacy to glimepiride after 2 years' treatment, with markedly reduced hypoglycaemia risk and no weight gain.

Simple pharmacometric tools for oral anti-diabetic drug development: competitive landscape for oral non-insulin therapies in type 2 diabetes

The objectives were to develop a translational model that will help select doses for Phase-3 trials based on abbreviated Phase-2 trials and understand the competitive landscape for oral anti-diabetics based on efficacy, tolerability and ability to slow disease progression. Data for eight anti-diabetics with temporal profiles for fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) from 12 publications were digitized. The monotherapy data consisted of FPG and HbA1c profiles that were modeled using a transit compartment model. Evaluation of the competitive landscape utilized HbA1c literature data for 11 drugs. For the safety metric, tolerability issues with anti-diabetic drug classes were tabulated. For disease progression, the coefficient of failure method was used for assessing data from two long-term trials. The transit rate constants were remarkably consistent across 12 trials and represent system-specific/drug-independent parameters. The competitive landscape analysis showed that the primary efficacy metric fell into two groups of DeltaHbA1c: >0.8% or approximately 0.8%. On the safety endpoints, older agents showed some tolerability issues while the new agents were relatively safe. Among the different drug classes, only the thiazolidinediones appeared to slow disease progression but may also increase heart failure risk. In conclusion, the ability of system-specific parameters to predict HbA1c provides a tool to predict the expected efficacy profile from abbreviated dose-finding trials. To be commercially viable, new drugs should improve DeltaHbA1c by about 0.8% or more and possess safety profiles similar to newer anti-diabetic agents. Thus, this study proposes a suite of simple yet powerful tools to guide type-2-diabetes drug development.

Defining and characterising the progression of type 2 diabetes

Type 2 diabetes is a progressive disease characterised by worsening of multiple abnormalities and loss of glycaemic control over time. An increasing need for glucose-lowering treatments is emphasised by the almost inevitable failure of monotherapy and occurrence of weight gain. Longer survival times and development of type 2 diabetes at a younger age also increase the risk of developing microvascular and macrovascular complications. A hallmark of type 2 diabetes mellitus is declining pancreatic β -cell function, which begins years before diagnosis and continues throughout the disease process. This deterioration continues despite initiation of numerous therapies, as these interventions lower glucose but do not directly slow β -cell decline and dysfunction. Defects in α-cell function are also important contributors to disease progression. New therapies that can counter these abnormalities without causing weight gain or hypoglycaemia continue to be assessed.Br J Diabetes Vasc Dis, 2008;8 (suppl 2): S3—S9

Colesevelam HCl improves glycemic control and reduces LDL cholesterol in patients with inadequately controlled type 2 diabetes on sulfonylurea-based therapy

OBJECTIVE

Hyperglycemia is a risk factor for microvascular complications and may increase the risk of cardiovascular disease in patients with type 2 diabetes. This study tested the LDL cholesterol-lowering agent colesevelam HCl (colesevelam) as a potential novel treatment for improving glycemic control in patients with type 2 diabetes on sulfonylurea-based therapy.

RESEARCH DESIGN AND METHODS

A 26-week, randomized, double-blind, placebo-controlled, parallel-group, multicenter study was carried out between August 2004 and August 2006 to evaluate the efficacy and safety of colesevelam for reducing A1C in adults with type 2 diabetes whose glycemic control was inadequate (A1C 7.5-9.5%) with existing sulfonylurea monotherapy or sulfonylurea in combination with additional oral antidiabetes agents. In total, 461 patients were randomized (230 given colesevelam 3.75 g/day and 231 given placebo). The primary efficacy measurement was mean placebo-corrected change in A1C from baseline to week 26 in the intent-to-treat population (last observation carried forward).

RESULTS

The least squares (LS) mean change in A1C from baseline to week 26 was -0.32% in the colesevelam group and +0.23% in the placebo group, resulting in a treatment difference of -0.54% (P < 0.001). The LS mean percent change in LDL cholesterol from baseline to week 26 was -16.1% in the colesevelam group and +0.6% in the placebo group, resulting in a treatment difference of -16.7% (P < 0.001). Furthermore, significant reductions in fasting plasma glucose, fructosamine, total cholesterol, non-HDL cholesterol, and apolipoprotein B were demonstrated in the colesevelam relative to placebo group at week 26.

CONCLUSIONS

Colesevelam improved glycemic control and reduced LDL cholesterol levels in patients with type 2 diabetes receiving sulfonylurea-based therapy.

[MicroRNAs: novel class of gene regulators involved in endocrine function and cancer]

MicroRNAs (miRNAs) represent a novel class of endogenous approximately 22-nucleotide RNAs that negatively regulate gene expression by inhibiting translation of target RNAs. Discovered just over a decade ago in Caenorhabditis elegans, miRNAs are now recognized as one of the major regulatory gene families in plants and animals. In the human genome, 462 miRNA genes have been discovered and the estimated number of miRNAs is as high as 1000. Bioinformatics analysis indicated that a unique miRNA acts on several mRNA, influencing multiple signaling pathways concomitantly, thus presenting enormous regulatory potential. Although the biology of miRNAs is not well understood, recent evidences have linked these molecules to diverse biological processes. Moreover, aberrant expression of miRNAs has been associated to human disease, including that related to the endocrine system and cancer.

A lifetime modelled economic evaluation comparing pioglitazone and rosiglitazone for the treatment of type 2 diabetes mellitus in the UK

INTRODUCTION

Adding pioglitazone or rosiglitazone to existing therapy are alternative treatment options for patients with type 2 diabetes mellitus who have insufficient glycaemic control while receiving the maximal tolerated dose of metformin monotherapy. Our objective was to develop a lifetime model of type 2 diabetes mellitus and its sequelae in order to compare the costs and benefits of pioglitazone versus rosiglitazone in combination with metformin.

METHODS

A decision-analytic model employing a first order Monte Carlo simulation of a Markov process was constructed. The model incorporated surrogate outcome measures from a large randomised controlled trial (RCT) [n = 802] that compared the glycaemic and lipid control of pioglitazone and rosiglitazone monotherapy. These efficacy data were used with a recently validated and peer-reviewed UKPDS (UK Prospective Diabetes Study) algorithm to simulate the progression of these surrogate outcomes to final health outcomes, including quality of life (QOL) and mortality, and to calculate the risks of diabetic complications and death. The model perspective was of the UK NHS and included direct healthcare costs only (pounds, 2004/5 values). Patient outcomes measured in the model included life-expectancy (LE) and QALYs. The base-case analysis was run for 56-year-old male Caucasions with a haemoglobin A(1c) (HbA(1c)) of 7.57% and a body mass index of 33.14 kg/m(2).

RESULTS

Patients treated with pioglitazone experienced a reduction in the total cholesterol to high-density lipoprotein-cholesterol (TC : HDL-C) ratio of 0.34, whereas the TC : HDL-C ratio increased by 0.65 in those receiving rosiglitazone (p < 0.001). The HbA(1c) profile was similar between the treatment groups (p = 0.13), as were other known risk factors for diabetes complications. The lifetime healthcare costs per patient estimated by the model were 9585 pounds for pioglitazone and 10,299 pounds for rosiglitazone. Patients treated with pioglitazone had a discounted LE of 8.83 years versus 8.79 years for those treated with rosiglitazone. Patients treated with pioglitazone also gained additional QALYs (6.8070 vs 6.7686). With improved health outcomes and lower costs, treatment with pioglitazone dominated rosiglitazone treatment.

CONCLUSION

Evidence from the only large head-to-head RCT comparing rosiglitazone and pioglitazone suggests that more favourable changes in serum lipid profiles in patients treated with pioglitazone translate into improved health outcomes in terms of reduced morbidity and mortality and greater gains in QOL. In addition, this analysis indicates that treatment with pioglitazone is associated with lower costs than rosiglitazone. Therefore, in the UK, adjunctive pioglitazone may represent a cost-effective treatment choice for patients with type 2 diabetes who have insufficient glycaemic control while receiving the maximal tolerated dose of metformin monotherapy.

Pioglitazona. Revisión de sus efectos metabólicos y sistémicos

Type 2 diabetes mellitus has become a true epidemic and significant growth is expected in the next decades. Thus it could be expected that the impact it may have on the incidence and prevalence of cardiovascular morbidity-mortality will have considerable magnitudes. It has been demonstrated that adequate metabolic control (glycemic and lipid) of these patients, beginning with diet and exercise programs and then with drug measures, decreases the risk of complications. However, several studies have shown that metabolic control deteriorates over time regardless of the treatment used. In recent years, a new drug family has been incorporated into the therapeutic armamentarium to treat type 2 diabetes mellitus. These are thiazolidinediones or glitazones, which have differential aspects regarding other drugs. In this article, the metabolic and systemic effects of pioglitazone, that have recently demonstrated a positive effect in the secondary prevention of cardiovascular episodes in the PROactive study have been reviewed.

Glycemic control continues to deteriorate after sulfonylureas are added to metformin among patients with type 2 diabetes

OBJECTIVE

To describe the course and predictors of glycemic control among patients with type 2 diabetes after sulfonylureas (SUs) are added to metformin (MF).

RESEARCH DESIGN AND METHODS

Patients (n = 2,220) treated with MF monotherapy for >90 days before initiating MF plus SU combination therapy between January 1998 and March 2004 were studied in a retrospective analysis of electronic medical records from U.K. primary care practices using the General Practice Research Database. Median glycoslyated hemoglobin A(1c) (A1C) before and after SU initiation was described, and patient characteristics were evaluated as predictors of time until A1C > or =8.0% or glucose-lowering therapy was intensified (by starting insulin or adding a third oral agent).

RESULTS

At 6 months post-SU initiation, median A1C resumed deteriorating at a somewhat comparable rate to that observed on MF monotherapy. Higher pre-SU A1C, younger age, female sex, shorter diabetes duration, higher serum creatinine, and being an ex-smoker predicted time until A1C > or =8.0% or glucose-lowering therapy was intensified in various analyses. Median A1C was 9.5% when therapy was intensified. A1C > or =8.0% was estimated to occur in 85% of patients 4 years after SU initiation and in 68% 4 years after initially achieving A1C <7% on MF plus SU therapy.

CONCLUSIONS

In this population, glycemic control is improved following the addition of SUs to MF, but deterioration resumes as early as 6 months. The high proportion of patients remaining on MF plus SU therapy despite having A1C > or =8.0% suggests that there are significant barriers to starting insulin or adding a third agent when treatment goals are not achieved with this combination.

Type 2 diabetes: principles of pathogenesis and therapy

Type 2 diabetes mellitus has become an epidemic, and virtually no physician is without patients who have the disease. Whereas insulin insensitivity is an early phenomenon partly related to obesity, pancreas beta-cell function declines gradually over time already before the onset of clinical hyperglycaemia. Several mechanisms have been proposed, including increased non-esterified fatty acids, inflammatory cytokines, adipokines, and mitochondrial dysfunction for insulin resistance, and glucotoxicity, lipotoxicity, and amyloid formation for beta-cell dysfunction. Moreover, the disease has a strong genetic component, but only a handful of genes have been identified so far: genes for calpain 10, potassium inward-rectifier 6.2, peroxisome proliferator-activated receptor gamma, insulin receptor substrate-1, and others. Management includes not only diet and exercise, but also combinations of anti-hyperglycaemic drug treatment with lipid-lowering, antihypertensive, and anti platelet therapy.

What impact would pancreatic beta-cell preservation have on life expectancy, quality-adjusted life expectancy and costs of complications in patients with type 2 diabetes? A projection using the CORE Diabetes Model

OBJECTIVE

Type 2 diabetes is characterised by progressive failure of pancreatic beta-cell function against a background of insulin resistance. Multifactorial interventions, including intensive glycaemic and blood pressure control, reduce the risk of onset and progression of complications. However, current management of type 2 diabetes focuses on treatment of signs and symptoms of disease instead of targeting underlying causes. A number of newer pharmacological interventions, including thiazolidinediones and glucagon-like peptides, have shown early promise in preserving pancreatic beta-cell function. The aim of this study was to investigate the impact of stabilising beta-cell function on long-term outcomes in patients with type 2 diabetes.

METHODS

The CORE Diabetes Model was used to project life expectancy (LE), quality-adjusted LE (QALE) and total lifetime complication costs (TC) for a cohort of newly-diagnosed patients with type 2 diabetes, either with a typical increase of HbA1c over time as observed in the UKPDS, or assuming stabilisation of HbA1c after diagnosis with a hypothetical new treatment, representing beta-cell function stabilisation. Costs due to diabetes-related complications (from a US third-party payer perspective), were discounted at 3% annually. Both non-discounted and discounted (at 3% annually) LE and QALE were calculated. Sensitivity analyses were performed to test the robustness of results.

RESULTS

Over a time period of 50 years, in a cohort with no increase of HbA1c over time, LE and QALE were improved by mean (SD) 1.02 (0.36) and 0.96 (0.25) years, and total costs of complications were reduced by 6,377 dollars (2,568) per patient compared to the cohort with a typical increase in HbA1c over time. Results were robust under a wide range of plausible assumptions.

CONCLUSIONS

New interventions that stabilise pancreatic betacell function may have an important impact on length and quality of life, and lead to reduced costs of complications in patients with type 2 diabetes.