Insulin-induced weight gain and cardiovascular events in patients with type 2 diabetes. A report from the DIGAMI 2 study

Empagliflozin treatment effects across categories of baseline HbA1c, body weight and blood pressure as an add-on to metformin in patients with type 2 diabetes

AIM

To investigate the association of different categories of baseline cardio-metabolic risk factors on the treatment effects of empagliflozin 10 and 25 mg when added as second-line therapy to metformin in patients with type 2 diabetes (T2D).

MATERIALS AND METHODS

Patients aged 18 years or older with HbA1c 7.0%-10.0% were included. Analysis of covariance compared change from baseline to weeks 24 and 76 in HbA1c, body weight (BW) and systolic blood pressure (SBP) by respective baseline categories (HbA1c <8.5/≥8.5%; BW <80/80-90/>90 kg, SBP <130/130-140/>140 mmHg). Analyses were also conducted with a model using continuous covariates of cardio-metabolic factors.

RESULTS

In total, 637 patients (56.7% males; mean [SD] age 55.7 [9.9] years, HbA1c 7.9% [0.9%], BW 81.2 [18.8] kg, SBP 129.4 [14.6] mmHg) received one or more dose of either empagliflozin 10 mg (n = 217) or 25 mg (n = 213), or placebo (n = 207). At both time points, empagliflozin 10/25 mg versus placebo significantly (P < .0001) reduced HbA1c and BW, with greater reductions in HbA1c at higher baseline HbA1c (P interaction week 24/76 categorical and continuous models: .0290/.1431 and .0004/.0042, respectively) and in BW (P interaction .1340/.0012 and .0202/<.0001, respectively). Both empagliflozin doses also significantly lowered SBP versus placebo at both time points, with similar efficacy by subgroups of baseline SBP. Adverse events were consistent with the established empagliflozin safety profile across treatment groups.

CONCLUSIONS

Empagliflozin, as add-on to metformin, decreases HbA1c and BW, particularly in patients with higher HbA1c and BW baseline values, and effectively lowers SBP.

Efficacy and Cardiovascular Safety of Antidiabetic Medications

Diabetes mellitus (DM) has already affected one in every eleven person in the global population, and the dis-ease prevalence continues to increase because of the obesity pandemic. Even with the availability of a multitude of antidi-abetic medications for optimal glycaemic control, cardiovascular morbidity and mortality were not largely altered until re-cently when newer antidiabetic drugs such as glucagon-like peptide-1 receptor analogues (GLP-1RAs) and sodium-glucose cotransporter-2 (SGLT2) inhibitors were introduced. Cardiovascular safety of antidiabetic drugs has also been a hot topic for global scientific debate after the US Food and Drug Administration (FDA) enforced restrictions on Rosiglita-zone in 2010 with the suspicion of increased mortality and myocardial events (with subsequent uplift of the ban on the drug in 2013 following the emergence of additional evidence on safety). After this debate, all antidiabetic should go through rigorous safety checks with cardiovascular outcome trials (CVOTs). Recent CVOTs with GLP-1RAs and SGLT2 inhibitors have revealed markedly positive outcomes that have changed the landscape of diabetes management across the world. Thus, the therapeutic algorithm for optimal management of DM should consider not only the glycaemic control ef-ficacy of the individual antidiabetic agent but also the cardiovascular safety and modifications in other anticipated long-term DM complication profiles. Therefore, it is imperative to critically appraise the efficacy and cardiovascular safety of all antidiabetic drugs to improve the scientific practice of our diabetes care globally. This issue, "Efficacy and cardiovas-cular safety of antidiabetic medications," provides readers the back-up of up to date evidence.

Insulin-associated weight gain in obese type 2 diabetes mellitus patients: What can be done?

Insulin therapy (IT) is initiated for patients with type 2 diabetes mellitus when glycaemic targets are not met with diet and other hypoglycaemic agents. The initiation of IT improves glycaemic control and reduces the risk of microvascular complications. There is, however, an associated weight gain following IT, which may adversely affect diabetic and cardiovascular morbidity and mortality. A 3 to 9 kg insulin-associated weight gain (IAWG) is reported to occur in the first year of initiating IT, predominantly caused by adipose tissue. The potential causes for this weight gain include an increase in energy intake linked to a fear of hypoglycaemia, a reduction in glycosuria, catch-up weight, and central effects on weight and appetite regulation. Patients with type 2 diabetes who are receiving IT often have multiple co-morbidities, including obesity, that are exacerbated by weight gain, making the management of their diabetes and obesity challenging. There are several treatment strategies for patients with type 2 diabetes, who require IT, that attenuate weight gain, help improve glycaemic control, and help promote body weight homeostasis. This review addresses the effects of insulin initiation and intensification on IAWG, and explores its potential underlying mechanisms, the predictors for this weight gain, and the available treatment options for managing and limiting weight gain.

Weight effects of antidiabetic agents

Obesity and diabetes are on the rise, which remains a continuous health concern worldwide. It is important to consider weight effects of antidiabetic agents prior to initiation as different antidiabetic agents impact weight differently. Areas covered: New agents to treat diabetes, glucagon-like peptide-1 receptor agonists and sodium glucose cotransporter 2 inhibitors, have emerged over recent years that have been shown to result in weight reduction. Unfortunately, other antidiabetic medications used can cause weight gain such as with insulin, sulfonylureas, and thiazolidediones while some remain weight neutral (metformin and dipeptidyl peptidase-4 inhibitors). The weight effects of these antidiabetic medications described are from select relevant guidelines, clinical trials, reviews, and meta-analysis found through PubMed and Ovid databases up to July 2017. Expert commentary: This article summarizes the current evidence available on the weight effects of these agents in patients with diabetes. Evaluating potential risks, such as weight gain, with potential benefits, such as improvement in glycemic control, will help with designing optimal therapeutic diabetes regimens.

Polycystic ovary syndrome and risk of endometrial, ovarian, and breast cancer: a systematic review

Background

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with an estimated prevalence of 4–21% in reproductive aged women. The altered metabolic and hormonal environment among women with PCOS may increase their risk of some types of cancer.

Methods

We performed a comprehensive review of the literature using numerous search terms for all studies examining the associations between polycystic ovary syndrome and related characteristics and cancer published in English through October 2016. This review summarizes the epidemiological findings on the associations between PCOS and endometrial, ovarian, and breast cancers and discusses the methodological issues, complexities, and underlying mechanisms of these associations.

Results

We identified 11 individual studies and 3 meta-analyses on the associations between PCOS and endometrial cancer, 8 studies and 1 meta-analysis for ovarian cancer, and 10 studies and 1 meta-analysis for breast cancer. Multiple studies reported that women with PCOS were at a higher risk for endometrial cancer; however, many did not take into account body mass index (BMI), a strong and well-established risk factor for endometrial cancer. The association with ovarian cancer was less clear, but a potentially increased risk of the borderline serous subtype was reported by two studies. No consistent association between PCOS risk and breast cancer was observed.

Conclusion

The associations between PCOS and endometrial, ovarian, and breast cancer are complex, with the need to consider many methodological issues in future analyses. Larger well-designed studies, or pooled analyses, may help clarify these complex associations.

Diabetes, diabetes severity, and coronary heart disease risk equivalence: REasons for Geographic and Racial Differences in Stroke (REGARDS)

BACKGROUND

Evidence is mixed regarding whether diabetes confers equivalent risk of coronary heart disease (CHD) as prevalent CHD. We investigated whether diabetes and severe diabetes are CHD risk equivalents.

METHODS

At baseline, participants in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study (black and white US adults ≥45 years old recruited in 2003-2007) were categorized as having prevalent CHD only (self-reported or electrocardiogram evidence; n = 3,043), diabetes only (self-reported or elevated glucose; n = 4,012), diabetes and prevalent CHD (n = 1,529), and neither diabetes nor prevalent CHD (n = 17,155). Participants with diabetes using insulin and/or with albuminuria (urinary albumin-to-creatinine ratio ≥30 mg/g) were categorized as having severe diabetes. Participants were followed up through 2011 for CHD events (myocardial infarction or fatal CHD).

RESULTS

During a mean follow-up of 5 years, 1,385 CHD events occurred. The hazard ratios of CHD events comparing participants with diabetes only, diabetes, and prevalent CHD and neither diabetes nor prevalent CHD with those with prevalent CHD were 0.65 (95% CI 0.54-0.77), 1.54 (95% CI 1.30-1.83), and 0.41 (95% CI 0.35-0.47), respectively, after adjustment for demographics and risk factors. Compared with participants with prevalent CHD, the hazard ratio of CHD events for participants with severe diabetes was 0.88 (95% CI 0.72-1.09).

CONCLUSIONS

Participants with diabetes had lower risk of CHD events than did those with prevalent CHD. However, participants with severe diabetes had similar risk to those with prevalent CHD. Diabetes severity may need consideration when deciding whether diabetes is a CHD risk equivalent.

Effects on All-cause Mortality and Cardiovascular Outcomes in Patients With Type 2 Diabetes by Comparing Insulin With Oral Hypoglycemic Agent Therapy: A Meta-analysis of Randomized Controlled Trials

PURPOSE

Retrospective, case-control studies and prospective randomized controlled trials (RCTs) on insulin treatment for diabetic patients yielded contradictory mortality and cardiovascular outcomes. We aimed to evaluate the effects of insulin versus oral hypoglycemic agents (OHAs) on all-cause mortality and cardiovascular outcomes in patients with type 2 diabetes (T2D).

METHODS

We searched Medline, Embase, Cochrane Central Register of Controlled Trials, Chinese Biological Medicine Database, China National Knowledge Infrastructure, Chinese Technical Periodicals, and Wanfang Data, up to July 10, 2015, for RCTs on insulin and OHAs that assessed all-cause mortality and/or cardiovascular death as primary end points. We derived pooled risk ratios (RRs) as summary statistics.

RESULTS

Three trials were included in which 7649 patients received insulin and 8322 received OHAs, with mean (SD) diabetes duration of 5.0 (6.2) and 4.4 (5.9) years, respectively. Insulin did not differ from OHAs in all-cause mortality (RR = 1.00; 95% CI, 0.93-1.07), cardiovascular death (RR = 1.00; 95% CI, 0.91-1.09), myocardial infarction (RR = 1.04; 95% CI, 0.93-1.16), angina (RR = 0.97; 95% CI, 0.88-1.06), sudden death (RR = 1.02; 95% CI, 0.66-1.56), or stroke (RR = 1.01; 95% CI, 0.88-1.15). Insulin reduced the risk of heart failure compared with OHAs (RR = 0.87; 95% CI, 0.75-0.99). In the subgroup of secondary prevention of cardiovascular diseases (CVDs) or very high risk of CVDs, insulin did not differ from OHAs in all-cause mortality (RR = 0.99; 95% CI, 0.92-1.07), cardiovascular death (RR = 0.99; 95% CI, 0.90-1.09), myocardial infarction (RR = 1.01; 95% CI, 0.88-1.15), heart failure (RR = 0.69; 95% CI, 0.34-1.40), or stroke (RR = 1.05; 95% CI, 0.90-1.21).

IMPLICATIONS

Insulin did not provide a clear benefit over OHAs in all-cause mortality or cardiovascular outcomes in the patients with T2D. Insulin therapy has many shortcomings, including inconvenience (injection, strict blood glucose monitoring), hypoglycemia, and obvious weight gain. Thus, we conclude that no robust evidence supports the active use of insulin for this population at present.

Cost effectiveness of dipeptidyl peptidase-4 inhibitors for type 2 diabetes

BACKGROUND

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of antidiabetic drugs used for treating type 2 diabetes mellitus. While many studies have reported on the cost-effectiveness of DPP-4 inhibitors for treating type 2 diabetes, a systematic review of economic evaluations of DPP-4 inhibitors is currently lacking.

OBJECTIVES

The aim of this systematic review was to assess the cost effectiveness of DPP-4 inhibitors for patients with type 2 diabetes.

DATA SOURCES

MEDLINE, EMBASE, National Health Service Economic Evaluation Database (NHS EED), Web of Science, EconLit databases, and the Cochrane Library were searched in November 2013.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

Studies assessing the cost effectiveness of DPP-4 inhibitors for type 2 diabetes were eligible for analysis. DPP-4 inhibitor monotherapy or combinations with other antidiabetic agents were included in the review. The DPP-4 inhibitors were all marketed drugs. Two reviewers independently reviewed titles, abstracts, and articles sequentially to select studies for data abstraction based on the inclusion and exclusion criteria. Disagreements were resolved by consensus.

STUDY APPRAISAL AND SYNTHESIS METHODS

The quality of included studies was assessed according to the 24-item checklist of the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement. The costs reported by the included studies were converted to US dollars via purchasing power parities (PPP) in the year 2013 using the CCEMG-EPPI-Center Cost Converter.

RESULTS

A total of 11 published studies were selected for inclusion; all were cost-utility analyses. Nine studies were conducted from a payer perspective and one used a societal perspective; however, the perspective of the other study was unclear. Four studies were of good quality, six were of moderate quality, and one was of low quality. Of the seven studies comparing DPP-4 inhibitors plus metformin with sulfonylureas plus metformin, six concluded that DPP-4 inhibitors were cost effective in patients with type 2 diabetes who were no longer adequately controlled by metformin monotherapy. Five studies compared DPP-4 inhibitors with thiazolidinediones, and whether DPP-4 inhibitors were cost effective was uncertain. Only two economic evaluations provided data to compare DPP-4 inhibitors versus insulin, and the results favored the use of DPP-4 inhibitors as second-line therapy.

LIMITATIONS

Synthesis of the data was impossible because of heterogeneity in the methodology and data sources of the economic evaluations, and the inclusion criteria excluded conference abstracts. It was difficult to find reliable weightings for each of the items of the CHEERS checklist, and the ratings were dichotomous.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

This study provides the first systematic evaluation of DPP-4 inhibitors for patients with type 2 diabetes. It found that, in patients with type 2 diabetes who do not achieve glycemic targets with antidiabetic monotherapy, DPP-4 inhibitors as add-on treatment may represent a cost-effective option compared with sulfonylureas and insulin. However, high-quality cost-effectiveness analyses that utilize long-term follow-up data and have no conflicts of interest are still needed.

"Symptom-based insulin adjustment for glucose normalization" (SIGN) algorithm: a pilot study

BACKGROUND

Lack of self-monitoring of blood glucose (SMBG) records in actual practice settings continues to create therapeutic challenges for clinicians, especially in adjusting insulin therapy. In order to overcome this clinical obstacle, a "Symptom-based Insulin adjustment for Glucose Normalization" (SIGN) algorithm was developed to guide clinicians in caring for patients with uncontrolled type 2 diabetes who have few to no SMBG records. This study examined the clinical outcome and safety of the SIGN algorithm.

SUBJECTS AND METHODS

Glycated hemoglobin (HbA1c), insulin usage, and insulin-related adverse effects of a total of 114 patients with uncontrolled type 2 diabetes who refused to use SMBG or performed SMBG once a day for less than three times per week were studied 3 months prior to the implementation of the algorithm and prospectively at every 3-month interval for a total of 6 months after the algorithm implementation. Patients with type 1 diabetes, nonadherence to diabetes medications, or who were not on insulin therapy at any time during the study period were excluded from this study.

RESULTS

Mean HbA1c improved by 0.29% at 3 months (P = 0.015) and 0.41% at 6 months (P = 0.006) after algorithm implementation. A slight increase in HbA1c was observed when the algorithm was not implemented. There were no major hypoglycemic episodes. The number of minor hypoglycemic episodes was minimal with the majority of the cases due to irregular meal habits.

CONCLUSIONS

The SIGN algorithm appeared to offer a viable and safe approach when managing uncontrolled patients with type 2 diabetes who have few to no SMBG records.

Targeting reperfusion injury in acute myocardial infarction: a review of reperfusion injury pharmacotherapy

INTRODUCTION

Acute myocardial infarction (AMI) (secondary to lethal ischemia-reperfusion [IR]) contributes to much of the mortality and morbidity from ischemic heart disease. Currently, the treatment for AMI is early reperfusion; however, this itself contributes to the final myocardial infarct size, in the form of what has been termed 'lethal reperfusion injury'. Over the last few decades, the discovery of the phenomena of ischemic preconditioning and postconditioning, as well as remote preconditioning and remote postconditioning, along with significant advances in our understanding of the cardioprotective pathways underlying these phenomena, have provided the possibility of successful mechanical and pharmacological interventions against reperfusion injury.

AREAS COVERED

This review summarizes the evidence from clinical trials evaluating pharmacological agents as adjuncts to standard reperfusion therapy for ST-elevation AMI.

EXPERT OPINION

Reperfusion injury pharmacotherapy has moved from bench to bedside, with clinical evaluation and ongoing clinical trials providing us with valuable insights into the shortcomings of current research in establishing successful treatments for reducing reperfusion injury. There is a need to address some key issues that may be leading to lack of translation of cardioprotection seen in basic models to the clinical setting. These issues are discussed in the Expert opinion section.

Overweight, obesity and central obesity in women with polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND Polycystic ovary syndrome (PCOS) is closely associated with obesity but the prevalence of obesity varies between published studies. The objective of this research was to describe the prevalence of overweight, obesity and central obesity in women with and without PCOS and to assess the confounding effect of ethnicity, geographic regions and the diagnostic criteria of PCOS on the prevalence. METHODS MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL) and PSYCINFO were searched for studies reporting the prevalence of overweight, obesity or central obesity in women with and without PCOS. Data were presented as prevalence (%) and risk ratio (RR) [95% confidence interval (CI)]. Random-effect models were used to calculate pooled RR. RESULTS This systematic review included 106 studies while the meta-analysis included 35 studies (15129 women). Women with PCOS had increased prevalence of overweight [RR (95% CI): 1.95 (1.52, 2.50)], obesity [2.77 (1.88, 4.10)] and central obesity [1.73 (1.31, 2.30)] compared with women without PCOS. The Caucasian women with PCOS had a greater increase in obesity prevalence than the Asian women with PCOS compared with women without PCOS [10.79 (5.36, 21.70) versus 2.31 (1.33, 4.00), P < 0.001 between subgroups). CONCLUSIONS Women with PCOS had a greater risk of overweight, obesity and central obesity. Although our findings support a positive association between obesity and PCOS, our conclusions are limited by the significant heterogeneity between studies and further studies are now required to determine the source of this heterogeneity. Clinical management of PCOS should include the prevention and management of overweight and obesity.

Weight and glycaemic control in type 2 diabetes: what is the outcome of insulin initiation?

AIMS

Little information is available on the association between obesity at time of insulin initiation and attainment of glycaemic targets in type 2 diabetic (T2DM) patients. This study describes changes in HbA1c, weight and body mass index (BMI) over 24 months postinsulin initiation.

METHODS

First-time insulin users with T2DM were selected from the UK General Practice Research Database for the period 1st January 2002 to 31st March 2008. The cohort was stratified into BMI categories (kg/m(2) ) at the time of insulin initiation. Data were reviewed at 6-monthly intervals. A multivariate repeated-measures linear model was fitted assessing weight change over 12 months.

RESULTS

3783 patients were included (normal weight, n = 672; overweight, n = 1259; obese, n = 1070; clinically obese, n = 480; morbidly obese, n = 302). The largest reductions in HbA1c were observed 6 months postinsulin initiation and were greatest in lower BMI categories: median observed HbA1c at initiation and 6 months was 9.7 and 7.9% in normal weight patients and 9.6 and 8.2% in the clinically obese, respectively. A minority of patients achieved HbA1c ≤ 7.5% and by 24 months the proportion achieving this was: normal weight 41%; overweight 34%; obese 30%; clinically obese 26%; morbidly obese 31%; trend p < 0.001. The greatest weight gain occured by 6 months and multivariate adjusted models showed that normal weight patients had the highest gains 5.07 kg (95% CI: 3.35, 6.79), as did those with HbA1c ≥ 12.1%-5.55 kg (95% CI: 3.81, 7.28).

CONCLUSION

Obesity is associated with a poorer response to insulin illustrated by higher HbA1c values and lower achievement of targets.

Prognostic implications of glucose-lowering treatment in patients with acute myocardial infarction and diabetes: experiences from an extended follow-up of the Diabetes Mellitus Insulin-Glucose Infusion in Acute Myocardial Infarction (DIGAMI) 2 Study

AIMS/HYPOTHESIS

This post hoc analysis from the Diabetes Mellitus Insulin-Glucose Infusion in Acute Myocardial Infarction (DIGAMI) 2 trial reports on extended long-term outcome in relation to glucose-lowering agents in patients with myocardial infarction and type 2 diabetes.

METHODS

Patients were randomised as follows: group 1, insulin-based treatment; group 2, insulin during hospitalisation followed by conventional glucose control; and group 3, conventional treatment. Treatment according to the above protocol lasted 2.1 years. Using the total DIGAMI 2 cohort as an epidemiological database, this study presents mortality rates in the randomised groups, and mortality and morbidity rates by glucose-lowering treatment during an extended period of follow-up (median 4.1 and max 8.1 years).

RESULTS

Follow-up data were available in 1,145 of the 1,253 patients. The mortality rate was 31% (72% cardiovascular) without significant differences between treatment groups. The total number of fatal malignancies was 37, with a trend towards a higher risk in group 1. The HR for death from malignant disease, compared with group 2, was 1.77 (95% CI 0.87-3.61; p = 0.11) and 3.60 (95% CI 1.24-10.50; p = 0.02) compared with group 3. Insulin treatment was associated with non-fatal cardiovascular events (OR 1.89 95% CI 1.35-2.63; p = 0.0002), but not with mortality (OR 1.30, 95% CI 0.93-1.81; p = 0.13). Metformin was associated with a lower mortality rate (HR 0.65, 95% CI 0.47-0.90; p = 0.01) and a lower risk of death from malignancies (HR 0.25, 95% CI 0.08-0.83; p = 0.02).

CONCLUSIONS/INTERPRETATION

Patients with type 2 diabetes and myocardial infarction have a poor prognosis. Glucose-lowering drugs appear to be of prognostic importance. Insulin may be associated with an increased risk of non-fatal cardiac events, while metformin seems to be protective against risk of death.

Evaluation of the weight-increasing effects of biphasic analog and regular NPH insulin mixtures in patients with Type 2 diabetes mellitus

BACKGROUND

Weight gain is a significant problem in diabetic patients in terms of worsening glycemic control, increasing diabetic and cardiovascular morbidity and mortality, and contributing to social and psychological problems. In the present study, we evaluated the effects of a biphasic analog and regular NPH insulin mixtures on weight gain in patients with Type 2 diabetes mellitus (T2DM) over 1 year.

METHODS

Group I consisted of 71 patients (29 men and 42 women) being treated with analog mixtures (insulin lispro 75/25 mix and biphasic insulin aspart 70/30 mix) twice daily; Group II consisted of 69 patients (23 men and 46 women) being treated with a regular insulin mixture (70/30) twice daily. Starting weight, body mass index, HbA1c, and hypoglycemic episodes were evaluated after 6 and 12 months.

RESULTS

Weight gain in Group I at 6 and 12 months was 1.41 ± 2.70 and 2.08 ± 3.74 kg, respectively. In Group II, weight gain at 6 and 12 months was 1.5 ± 3.0 and 2.29 ± 3.85 kg, respectively. Intragroup comparisons indicated that, for both groups, weight gain at 6 and 12 months differed significantly from the starting weight. However, no significant differences in weight gain were found between the two groups (P > 0.05).

CONCLUSIONS

The weight-increasing effects of an analog mixture of insulin and the NPH regular mixture of insulin appear to be similar. This should be taken into account when determining the type of insulin to use in treating T2DM patients.

Impact of data from recent clinical trials on strategies for treating patients with type 2 diabetes mellitus

Type 2 diabetes is associated with increased risk for the development of cardiovascular disease (CVD) secondary to hyperglycemia’s toxicity to blood vessels. The escalating incidence of CVD among patients with type 2 diabetes has prompted research into how lowering glycated hemoglobin (HbA_1c) may improve CVD-related morbidity and mortality. Data from recent studies have shown that some patients with type 2 diabetes actually have increased mortality after achieving the lowest possible HbA_1c using intensive antidiabetes treatment. Multiple factors, such as baseline HbA_1c, duration of diabetes, pancreatic β-cell decline, presence of overweight/obesity, and the pharmacologic durability of antidiabetes medications influence diabetes treatment plans and therapeutic results. Hypertension and dyslipidemia are common comorbidities in patients with type 2 diabetes, which impact the risk of CVD independently of glycemic control. Consideration of all of these risk factors provides the best option for reducing morbidity and mortality in patients with type 2 diabetes. Based on the results of recent trials, the appropriate use of current antidiabetes therapies can optimize glycemic control, but use of intensive glucose-lowering therapy will need to be tailored to individual patient needs and risks.

Insulin use and increased risk of mortality in type 2 diabetes: a cohort study

AIM

To compare population-based rates of all-cause and cardiovascular (CV) mortality in newly treated patients with type 2 diabetes according to levels of insulin exposure.

METHODS

Using the administrative databases of Saskatchewan Health, 12272 new users of oral antidiabetic therapy were identified between 1991 and 1996 and grouped according to cumulative insulin exposure based on total insulin dispensations per year: no exposure (reference group); low exposure (0 to <3); moderate exposure (3 to <12) and high exposure (> or =12). Time-varying multivariable Cox proportional hazards models were used to examine the relationship between insulin exposure and all-cause, CV-related and non-vascular mortality after adjustment for demographics, medications and comorbidities.

RESULTS

Average age was 65 (s.d. 13.9) years, 45% were female, and mean follow-up was 5.1 (s.d. 2.2) years. In total, 1443 (12%) subjects started insulin, and 2681 (22%) deaths occurred. The highest mortality rates were in the high exposure group; 95 deaths/1000 person-years compared with 40 deaths/1000 person-years in the no exposure group [unadjusted hazard ratio (HR): 2.32; 95% confidence interval (CI): 1.96-2.73]. After adjustment, we observed a graded risk of mortality associated with increasing exposure to insulin: low exposure [adjusted HR (aHR): 1.75; 95% CI: 1.24-2.47], moderate exposure (aHR: 2.18; 1.82-2.60) and high exposure (aHR: 2.79; 2.36-3.30); p = 0.005 for trend. Analyses restricted to CV-related (p = 0.042 for trend) and non-vascular (p = 0.004 for trend) mortality showed virtually identical results.

CONCLUSIONS

We observed a significant and graded association between mortality risk and insulin exposure level in an inception cohort of patients with type 2 diabetes that persisted despite multivariable adjustment.