Macrovascular and microvascular outcomes after beginning of insulin versus additional oral glucose-lowering therapy in people with type 2 diabetes: an observational study

Risk factors for peripheral artery disease and diabetic peripheral neuropathy among patients with type 2 diabetes

AIMS

To investigate the prevalence of peripheral artery disease (PAD) and diabetic peripheral neuropathy (DPN) and the associated risk factors among Chinese patients with type 2 diabetes mellitus.

METHODS

A cross-sectional study was conducted using data between November 1, 2018, and December 31, 2022. PAD was defined as ABI ≤ 0.9. DPN diagnosis involved specialized physician assessments using questionnaires and vibration perception threshold tests. Logistic regression analysis was used to identify related factors. We also evaluated the association between the clustering of risk factors and disease incidence.

RESULTS

The study population comprised 13,315 patients (mean age: 63.3 years). 4.9 % of the patients had PAD and 43.9 % had DPN. Multivariate regression analysis revealed advanced age, smoking, hypertension, coronary heart disease, dyslipidemia, elevated HbA1c, and uric acid levels as independent risk factors for PAD. For DPN, independent risk factors included advanced age, female gender, hypertension, coronary heart disease, elevated total cholesterol, triglycerides, lipoprotein(a), fasting plasma glucose, HbA1c, alkaline phosphatase, cystatin C, albumin-to-creatinine ratio, and elevated homocysteine levels, whereas apolipoprotein A was a protective factor. The clustering of risk factors was prevalent and associated with higher disease risk.

CONCLUSIONS

Our study contributed to identifying high-risk individuals and improving lower limb health among diabetic individuals.

Impacts of early insulin treatment vs glimepiride in diabetic patients with background metformin therapy: A nationwide retrospective cohort study

ABSTRACT

Type 2 diabetes mellitus (T2DM) is a progressive disease. After metformin failure, the addition of insulin or sulfonylureas might increase the risk of hypoglycemia and cardiovascular (CV) morbidity. Here, the risk of all-cause mortality was compared between early insulin treatment and glimepiride use in T2DM patients with background metformin therapy.We conducted a 9-year retrospective cohort study from the population-based National Health Insurance Research Database in Taiwan. A total of 2054 patients with T2DM under insulin or glimepiride treatment were enrolled during 2004 to 2012. Overall event rates of all-cause mortality were compared between 1027 insulin users and 1027 matched glimepiride users.After the propensity score matching, the mortality rates were 72.5 and 4.42 per 1000 person-years for insulin users and glimepiride users. The adjusted hazard ratio of mortality was 14.47 (95% CI: 8.64-24.24; P value <.001) as insulin compared with glimepiride users. The insulin users had significantly higher risk of CV death (adjusted hazard ratio 7.95, 95% CI 1.65-38.3, P = .01) and noncardiovascular death (adjusted hazard ratio 14.9, 95% CI 8.4-26.3, P < .001).The nationwide study demonstrated that metformin plus insulin therapy was associated with higher risk of all-cause mortality.

Exploring novel diabetes surveillance methods: a comparison of administrative, laboratory and pharmacy data case definitions using THIN

Background

The objective of this study was to identify patients with diabetes in a comprehensive primary care electronic medical records database using a number of different case definitions (clinical, pharmacy, laboratory definitions and a combination thereof) and understand the differences in patient populations being captured by each definition.

Methods

Data for this population-based retrospective cohort study was obtained from The Health Information Network (THIN). THIN is a longitudinal, primary care medical records database of over 9 million patients in UK. Primary outcome was a diagnosis of diabetes, defined by the presence of a diabetes read code, or an abnormal laboratory result, or a prescription for an Oral Anti-diabetic drug or insulin. A 2-year washout period was applied prior to the index of diabetes to avoid inclusion of prevalent cases for each case definition.

Results

This study demonstrated that different case definitions of diabetes identify different sub-populations of patients. When the cohorts were observed based on any measure of central tendency, each of the cohorts were reasonably comparable to each other. However, the distribution of each of the cohorts when grouped by age categories and sex, reveal differences. For example, using pharmacy case definition results in a bimodal distribution among women, one between 1-19 year and 35-39 age categories, and then again between 60-64 and 85 years-however, the histogram becomes more normally distributed when metformin was removed from the case definition.

Conclusion

Our results suggest that clinical, pharmacy, laboratory case definitions identify different sub-populations and using multiple case definitions is likely required to optimally identify the entire diabetes population within THIN. Our study also suggests that age and sex of patients may affect the indexing of diabetes in THIN and is critical to better understand these variations.

Comparative risk of major cardiovascular events associated with second-line antidiabetic treatments: a retrospective cohort study using UK primary care data linked to hospitalization and mortality records

AIMS

To examine the risk of major cardiovascular events associated with second-line diabetes therapies, in patients with type 2 diabetes, after adjusting for known cardiovascular risk factors.

METHODS

This was a retrospective cohort study of patients prescribed second-line regimens between 1998 and 2011 after first-line metformin. The UK Clinical Practice Research Datalink, with linked national hospitalization and mortality data, for the period up to December 2013, was used. Inverse probability of treatment-weighted time-varying Cox regression models was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for developing a major cardiovascular event (cardiovascular death, myocardial infarction, stroke, acute coronary syndrome, unstable angina, or coronary revascularization) associated with second-line therapies. Analyses adjusted for patient demographic characteristics, comorbidities, glycated haemoglobin, socio-economic status, ethnicity, smoking status and concurrent medications.

RESULTS

A total of 10 118 initiators of a second-line add-on to metformin of either a sulphonylurea (n = 6740), dipeptidyl peptidase-4 (DPP-4) inhibitor (n = 1030) or thiazolidinedione (n = 2348) were identified. After a mean (standard deviation) of 2.4 (1.9) years of follow-up, 386, 36 and 95 major cardiovascular events occurred in sulphonylurea-, DPP-4 inhibitor- and thiazolidinedione-initiators, respectively. In comparison with the metformin-sulphonylurea regimen, adjusted HRs were 0.78 (95% CI 0.55; 1.11) for the metformin-DPP-4 inhibitor regimen and 0.68 (95% CI 0.54; 0.85) for the metformin-thiazolidinedione regimen.

CONCLUSIONS

Thiazolidinedione add-on treatments to metformin were associated with lower risks of major cardiovascular disease or cardiovascular death compared with sulphonylurea add-on treatment to metformin. Lower, but non-statistically significant, risks were also found with DPP-4 inhibitor add-on therapies.

Four-year evolution of insulin regimens, glycaemic control, hypoglycaemia and body weight after starting insulin therapy in type 2 diabetes across three continents

AIMS

It is of interest to understand how insulin therapy currently evolves in clinical practice, in the years after starting insulin in people with type 2 diabetes. We aimed to describe this evolution prospectively over 4 years, to assist health care planning.

METHODS

People who had started any insulin were identified from 12 countries on three continents. Baseline, then yearly follow-up, data were extracted from clinical records over 4 years.

RESULTS

Of the 2999 eligible people, 2272 were followed over 4 years. When starting insulin, mean (SD) duration of diabetes was 10.6 (7.8) years, HbA1c 9.5 (2.0)% (80 [22]mmol/mol) and BMI 29.3 (6.3)kg/m(2). Initial insulin therapy was basal 52%, premix 23%, mealtime+basal 14%, mealtime 8% and other 3%; at 4 years, 30%, 25%, 33%, 2% and 5%, respectively, with 5% not on insulin. Insulin dose was 20.2U/day at the start and 45.8U/day at year 4. There were 1258 people (55%) on their original regimen at 4 years, and this percentage differed according to baseline insulin regimen. HbA1c change was -2.0 (2.2)% (-22 [24]mmol/mol) and was similar by final insulin regimen. Hypoglycaemia prevalence was <20% in years 1-4. Body weight change was mostly in year 1, and was very variable, mean +2.7 (7.5)kg at year 4.

CONCLUSION

Different insulin regimens were started in people with differing characteristics, and they evolved differently; insulin dose, hypoglycaemia and body weight change were diverse and largely independent of regimen.

A review of cardiovascular outcomes in the treatment of people with type 2 diabetes

INTRODUCTION

Cardiovascular disease (CVD) is a common and serious complication of type 2 diabetes mellitus (T2DM) often linked to the increased morbidity and mortality associated with T2DM. Monitoring and treating risk factors for CVD are important elements of diabetes management. This review aims to examine CV risk in people with relatively early and mild diabetes who are at substantial risk of CVD; it considers the impact of insulin therapy on this risk by focusing on key studies in patients with diabetes.

METHODS

A literature search was carried out using PubMed to identify key publications, between 2008 and 2013, related to insulin and its possible effect on CVD. This review examines CV risk in diabetes and the impact of insulin therapy on this risk.

RESULTS

Studies have shown that treatment with insulin glargine is associated with marked improvement in the lipid profile of people with T2DM. Intensive insulin therapy has been shown to lower mortality rates in people with diabetes following acute myocardial infarction after 1 year. Retrospective data also indicate that insulin reduces the risk of CVD events, regardless of whether people had comorbidities known to increase CV risk. The prospective ORIGIN (Outcome Reduction with Initial Glargine Intervention) trial found that treatment with insulin glargine had a neutral effect with regard to CV outcomes in people with prediabetes or early diabetes, compared with standard care.

CONCLUSIONS

Other ongoing, large-scale studies of insulin therapy should provide further insights into whether or not insulin therapy can influence long-term CV outcomes.

Association of impaired fasting glucose, diabetes and their management with the presentation and outcome of peripheral artery disease: a cohort study

Background

Pre-diabetes and untreated diabetes are common in patients with peripheral artery disease however their impact on outcome has not been evaluated. We examined the association of impaired fasting glucose, diabetes and their treatment with the presentation, mortality and requirement for intervention in peripheral artery disease patients.

Methods

We prospectively recruited 1637 patients with peripheral artery disease, measured fasting glucose, recorded medications for diabetes and categorised them by diabetes status. Patients were followed for a median of 1.7 years.

Results

At entry 22.7% patients were receiving treatment for type 2 diabetes by oral hypoglycaemics alone (18.1%) or insulin (4.6%). 9.2% patients had non-medicated diabetes. 28.1% of patients had impaired fasting glucose (5.6-6.9 mM). Patients with non-medicated diabetes had increased mortality and requirement for peripheral artery intervention (hazards ratio 1.62 and 1.31 respectively). Patients with diabetes prescribed insulin had increased mortality (hazard ratio 1.97). Patients with impaired fasting glucose or diabetes prescribed oral hypoglycaemics only had similar outcomes to patients with no diabetes.

Conclusions

Non-medicated diabetes is common in peripheral artery disease patients and associated with poor outcomes. Impaired fasting glucose is also common but does not increase intermediate term complications. Peripheral artery disease patients with diabetes requiring insulin are at high risk of intermediate term mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-014-0147-2) contains supplementary material, which is available to authorized users.

Associations between different types of hypoglycemic agents and the clinical outcome of percutaneous coronary intervention in diabetic patients-From the FU-Registry

BACKGROUND

It is not clear whether it is reasonable to use particular drugs for glycemic control in preference to other hypoglycemic agents in terms of the clinical outcome of percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM).

METHODS AND RESULTS

Among 2148 patients (2568 lesions) in the FU-Registry, DM patients who underwent PCI (n=758; 922 lesions) were investigated to clarify the effects of various drugs for glycemic control on the clinical outcome [major adverse cardiac events (MACEs): death, myocardial infarction (MI), and target lesion revascularization (TLR)] over approximately 300 days of follow-up (UMIN000005679). The MACEs(+) group (n=165) had a higher usage of insulin (p<0.001) and a lower usage of biguanides (BG, p<0.05) and dipeptidyl peptidase-IV inhibitors (p<0.05) at PCI, compared to the MACEs(-) group (n=593). A multivariate logistic regression analysis showed that low-density lipoprotein cholesterol, insulin use, atherosclerosis obliterans, and lesion reference might be significantly associated with MACEs, while BG use was negatively correlated with MACEs (p=0.04). The cumulative frequency of MACEs in the insulin-treated group was significantly higher (p<0.05) than that in the non-insulin group, and the strongest association between insulin with MACEs was seen in the hemoglobin (Hb) A1c 6.5-7.5% group. There tended to be a negative correlation between the use of insulin and MACEs, with risk ratios of <1, for the HbA1c >8.5% groups.

CONCLUSIONS

Among different hypoglycemic agents, treatment with insulin was associated with poor mid-term clinical outcomes in DM patients who underwent PCI, while BG use was negatively correlated with MACEs. It may be reasonable for patients with HbA1c >8.5% to avoid hyperglycemia and glucotoxicity, even through the use of insulin.

Distinguishing incident and prevalent diabetes in an electronic medical records database

PURPOSE

To develop a method to identify incident diabetes mellitus (DM) using an electronic medical records (EMR) database and test this classification by comparing incident and prevalent DM with common outcomes related to DM duration.

METHODS

Incidence rates (IRs) of DM (defined as a first diagnosis or prescription) were measured in 3-month intervals through 36 months after registration in The Health Improvement Network, a primary care database, from 1994 to 2012. We used Joinpoint regression to identify the point where a statistically significant change in the trend of IRs occurred. Further analyses used this point to distinguish those likely to have incident (n = 50 315) versus prevalent (n = 28 337) DM. Incident and prevalent cohorts were compared using Cox regression for all-cause mortality, cardiovascular disease (CVD), diabetic retinopathy, diabetic nephropathy, and diabetic neuropathy. Analyses were adjusted for age, sex, smoking, obesity, hyperlipidemia, hypertension, and calendar year.

RESULTS

Trends in DM IRs plateaued 9 months after registration (p = 0.04). All cause-mortality was increased (hazard ratio (HR) 1.62, 95% CI 1.53-1.70) among patients diagnosed with DM prior to 9 months following registration (prevalent DM) compared to those diagnosed after 9 months (incident DM). Similarly, the risk of DM-related complications was higher in prevalent versus incident DM patients [CVD, HR 2.24 (2.08-2.40); diabetic retinopathy, HR 1.31 (1.24-1.38); diabetic nephropathy, HR 2.30 (1.95-2.72); diabetic neuropathy, HR 1.28 (1.16-1.41)].

CONCLUSION

Joinpoint regression can be used to identify patients with newly diagnosed diabetes within EMR data. Failure to exclude patients with prevalent DM can lead to exaggerated associations of DM-related outcomes.

Primary-care observational database study of the efficacy of GLP-1 receptor agonists and insulin in the UK

AIMS

We investigated use and efficacy of glucagon-like peptide-1 (GLP-1) receptor agonists in UK practice.

METHODS

People starting a GLP-1 receptor agonist (exenatide, liraglutide) or insulin (glargine, detemir, NPH) after a regimen of two or three oral glucose-lowering agents were identified from The Health Information Network observational primary care database (2007-2011). Mean change in HbA1c and body weight were compared at 1 year between cohorts, adjusting for baseline characteristics.

RESULTS

Baseline characteristics of GLP-1 receptor agonist (n = 1123) vs. insulin (n = 1842) users were HbA1c 78 vs. 84 mmol/mol (9.3 vs. 9.8%) and BMI 38.2 vs. 30.9 kg/m². The GLP-1 receptor agonist cohort was younger, had shorter diabetes duration and follow-up, less microvascular disease and heart failure, higher estimated glomerular filtration rate and more use of oral glucose-lowering agents. Lower HbA1c reduction on GLP-1 receptor agonist [7 vs. 13 mmol/mol (0.6 vs. 1.2%) (n = 366 vs. 892)] was not statistically significant [adjusted mean difference -1.4 (95% CI -4.1, 1.2) mmol/mol], except in the highest HbA1c quintile [>96 mmol/mol (>10.9%); adjusted mean difference -17.8 (-28.6, -7.0) mmol/mol]. GLP-1 receptor agonist users lost weight [-4.5 vs. +1.5 kg; adjusted mean difference 4.7 (3.7, 5.8) kg; n = 335 vs. 634]. A UK 6-month target reduction for GLP-1 receptor agonists of 11 mmol/mol (1.0%) HbA1c and 3% weight was reached by 24.9% of those continuing treatment.

CONCLUSIONS

Those starting GLP-1 receptor agonists are heavier with better glycaemic control than those starting basal insulin. Subsequently, they have improved weight change, with similar HbA1c reduction unless baseline HbA1c is very high. The UK 6-month GLP-1 receptor agonist target is usually not reached.

Observational study of the association of first insulin type in uncontrolled type 2 diabetes with macrovascular and microvascular disease

Aims

To compare the risk of vascular disease, HbA1c and weight change, between first prescribed insulins in people with type 2 diabetes.

Methods

People included in THIN United Kingdom primary care record database who began insulin (2000–2007) after poor control on oral glucose-lowering agents (OGLD) were grouped by the number of OGLDs in their treatment regimen immediately before starting insulin (n = 3,485). Within OGLD group, Cox regression compared macrovascular (all-cause mortality, myocardial infarction, acute coronary syndrome and stroke) and microvascular disease (peripheral neuropathy, nephropathy, and retinopathy) between insulin type (basal, pre-mix or Neutral Protamine Hagedorn, NPH) while ANCOVAs compared haemoglobin A_1c (HbA_1c) and weight change.

Results

Mean follow-up was 3.6 years. Rates of incident macrovascular events were similar when basal insulin was compared to pre-mix or NPH, adjusted hazard ratio versus basal: pre-mix 1.08 (95% CI 0.73, 1.59); NPH 1.00 (0.63, 1.58) after two OGLDs, and pre-mix 0.97 (0.46, 2.02); NPH 0.77 (0.32, 1.86) after three OGLDs. An increased risk of microvascular disease in NPH versus basal after 3 OGLDs, adjusted hazard ratio1.87 (1.04, 3.36), was not seen after two agents or in comparisons of basal and pre-mix. At one year, after two OGLDs, weight increase was less with basal compared with pre-mix. After three OGLDs, mean HbA_1c had reduced less in basal versus pre-mix or NPH at 6–8 and at 9–11 months, and versus pre-mix at 12–14 months.

Conclusion

We found no difference in the risk of macrovascular events between first insulins in the medium term when started during poor glycaemia control. The increased risk of microvascular events with NPH warrants further study. In certain groups, first use of basal insulin was associated with less gain in weight and decrease in HbA_1c compared to other insulins.