Preexisting Diabetes Mellitus and All-Cause Mortality in Adult Patients With Sepsis: A Population-Based Cohort Study

OBJECTIVES

We assessed the association of preexisting diabetes mellitus with all-cause mortality and organ support receipt in adult patients with sepsis.

DESIGN

Population-based cohort study.

SETTING

Ontario, Canada (2008-2019).

POPULATION

Adult patients (18 yr old or older) with a first sepsis-related hospitalization episode.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main exposure of interest was preexisting diabetes (either type 1 or 2). The primary outcome was all-cause mortality by 90 days; secondary outcomes included receipt of invasive mechanical ventilation and new renal replacement therapy. We report adjusted (for baseline characteristics using standardization) risk ratios (RRs) alongside 95% CIs. A main secondary analysis evaluated the potential mediation by prior metformin use of the association between preexisting diabetes and all-cause mortality following sepsis. Overall, 503,455 adults with a first sepsis-related hospitalization episode were included; 36% had preexisting diabetes. Mean age was 73 years, and 54% of the cohort were females. Preexisting diabetes was associated with a lower adjusted risk of all-cause mortality at 90 days (RR, 0.81; 95% CI, 0.80-0.82). Preexisting diabetes was associated with an increased risk of new renal replacement therapy (RR, 1.53; 95% CI, 1.46-1.60) but not invasive mechanical ventilation (RR, 1.03; 95% CI, 1.00-1.05). Overall, 21% (95% CI, 19-28) of the association between preexisting diabetes and reduced risk of all-cause mortality was mediated by prior metformin use.

CONCLUSIONS

Preexisting diabetes is associated with a lower risk of all-cause mortality and higher risk of new renal replacement therapy among adult patients with sepsis. Future studies should evaluate the underlying mechanisms of these associations.

Risk of Breast Cancer After Diabetes in Pregnancy: A Population-based Cohort Study

OBJECTIVES

Diabetes is associated with an increased risk of several cancers, including postmenopausal breast cancer. The evidence for higher breast cancer risk after diabetes in pregnancy is conflicting. We compared the incidence of breast and other cancers between pregnant women with and without diabetes.

METHODS

This work was a propensity-matched, retrospective cohort study using population-based health-care databases from Ontario, Canada. Those deliveries with gestational diabetes mellitus (GDM) and pregestational diabetes mellitus (pregestational DM) were identified and matched to deliveries without diabetes mellitus (non-DM). Deliveries from each diabetes cohort were matched 1:2 on age, parity, year of delivery, and propensity score to non-DM deliveries. Matched subjects were followed from delivery for incidence of breast cancer as a primary outcome, and other site-specific cancers as secondary outcomes. We performed Cox proportional hazards regression to compare rates of breast cancer between matched groups.

RESULTS

Over a median of 8 (interquartile range 4 to 13) years of follow-up, compared with non-DM deliveries, the incidence of breast cancer was significantly lower for GDM but similar for pregestational DM deliveries (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.82 to 0.98; and HR 0.92, 95% CI 0.80 to 1.07, respectively). GDM was associated with a significantly higher incidence of pancreatic and hepatocellular cancer, and pregestational DM was associated with a higher incidence of thyroid, hepatocellular, and endometrial cancers.

CONCLUSIONS

Diabetes in pregnancy does not have a higher short-term risk of subsequent breast cancer, but there may be a higher incidence of other cancers.

Risk Prediction Scores for Type 2 Diabetes Microvascular and Cardiovascular Complications Derived and Validated With Real-world Data From 2 Provinces: The DIabeteS COmplications (DISCO) Risk Scores

OBJECTIVES

Existing tools to predict the risk of complications among people with type 2 diabetes poorly discriminate high- from low-risk patients. Our aim in this study was to develop risk prediction scores for major type 2 diabetes complications using real-world clinical care data, and to externally validate these risk scores in a different jurisdiction.

METHODS

Using health-care administrative data and electronic medical records data, risk scores were derived using data from 25,088 people with type 2 diabetes from the Canadian province of Ontario, followed between 2002 and 2017. Scores were developed for major clinically important microvascular events (treatment for retinopathy, foot ulcer, incident end-stage renal disease), cardiovascular disease events (acute myocardial infarction, heart failure, stroke, amputation), and mortality (cardiovascular, noncardiovascular, all-cause). They were then externally validated using the independent data of 11,416 people with type 2 diabetes from the province of Manitoba.

RESULTS

The 10 derived risk scores had moderate to excellent discrimination in the independent validation cohort, ranging from 0.705 to 0.977. Their calibration to predict 5-year risk was excellent across most levels of predicted risk, albeit with some displaying underestimation at the highest levels of predicted risk.

CONCLUSIONS

The DIabeteS COmplications (DISCO) risk scores for major type 2 diabetes complications were derived and externally validated using contemporary real-world clinical data. As a result, they may be more accurate than other risk prediction scores derived using randomized trial data. The use of more accurate risk scores in clinical practice will help improve personalization of clinical care for patients with type 2 diabetes.

An assessment of adaptation and fidelity in the implementation of an audit and feedback-based intervention to improve transition to adult type 1 diabetes care in Ontario, Canada

BACKGROUND

The fit between an intervention and its local context may affect its implementation and effectiveness. Researchers have stated that both fidelity (the degree to which an intervention is delivered, enacted, and received as intended) and adaptation to the local context are necessary for high-quality implementation. This study describes the implementation of an audit and feedback (AF)-based intervention to improve transition to type 1 diabetes adult care, at five sites, in terms of adaptation and fidelity.

METHODS

An audit and feedback (AF)-based intervention for healthcare teams to improve transition to adult care for patients with type 1 diabetes was studied at five pediatric sites. The Framework for Reporting Adaptations and Modifications to Evidence-based Implementation Strategies (FRAME-IS) was used to document the adaptations made during the study. Fidelity was determined on three different levels: delivery, enactment, and receipt.

RESULTS

Fidelity of delivery, receipt, and enactment were preserved during the implementation of the intervention. Of the five sites, three changed their chosen quality improvement initiative, however, within the parameters of the study protocol; therefore, fidelity was preserved while still enabling participants to adapt accordingly.

CONCLUSIONS

We describe implementing a multi-center AF-based intervention across five sites in Ontario to improve the transition from pediatric to adult diabetes care for youth with type 1 diabetes. This intervention adopted a balanced approach considering both adaptation and fidelity to foster a community of practice to facilitate implementing quality improvement initiatives for improving transition to adult diabetes care. This approach may be adapted for improving transition care for youth with other chronic conditions and to other complex AF-based interventions.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03781973. Registered 13 December 2018. Date of enrolment of the first participant to the trial: June 1, 2019.

Determinants, Prevention, and Incidence of Cardiovascular Disease Among Immigrant and Refugee Populations

Immigration policies shape the composition, socioeconomic characteristics, and health of migrant populations. The health of migrants is also influenced by a confluence of social, economic, environmental, and political factors. Immigrants and refugees often face various barriers to accessing health care because of factors such as lack of familiarity with navigating the health care system, language barriers, systemic racism, and gaps in health insurance. Social determinants of health and access to primary care health services likely influence the burden of cardiovascular risk factors among immigrants. The relatively low burden of many cardiovascular risk factors in many immigrant populations likely contributes to the generally lower incidence rates of acute myocardial infarction, heart failure, and stroke in immigrants compared with nonimmigrants, although cardiovascular disease incidence rates vary substantially by country of origin. The "healthy immigrant effect" is the hypothesis that immigrants to high-income countries, such as Canada, are healthier than nonimmigrants in the host population. However, this effect may not apply universally across all immigrants, including recent refugees, immigrants without formal education, and unmarried immigrants. As unfolding sociopolitical events generate new waves of global migration, policymakers and health care providers need to focus on addressing social and structural determinants of health to better manage cardiovascular risk factors and prevent cardiovascular disease, especially among the most marginalized immigrants and refugees.

Association Between Age at Diagnosis of Type 2 Diabetes and Hospitalization for Heart Failure: A Population-Based Study

BACKGROUND

The relation between age at diagnosis of type 2 diabetes (T2D) and hospitalization for heart failure (HHF) is unclear. We assessed the association between age at diagnosis of T2D and HHF.

METHODS AND RESULTS

We conducted a population-based cohort study using administrative health databases from the Canadian province of Ontario, including participants without prior heart failure. We identified people with new-onset T2D between April 1, 2005 and March 31, 2015, and matched each person with 3 diabetes-free adults, according to birth year and sex. We estimated adjusted hazard ratios (HRs) and rate ratios (RRs) for the association between age at T2D diagnosis and incident HHF, which was assessed until March 31, 2020. Among 743 053 individuals with T2D and 2 199 539 matched individuals without T2D, 126 241 incident HHF events occurred over 8.9 years. T2D was associated with a greater adjusted hazard of HHF at younger ages (eg, HR at age 30 years: 6.94 [95% CI, 6.54-7.36]) than at older ages (eg, HR at age 60 years: 2.50 [95% CI, 2.45-2.56]) relative to matched individuals. Additional adjustment for mediators (hypertension, coronary artery disease, and chronic kidney disease) marginally attenuated this relationship. Age at T2D diagnosis was associated with a greater number of HHF events relative to matched individuals at younger ages (eg, RR at age 30 years: 6.39 [95% CI, 5.76-7.08]) than at older ages (eg, RR at age 60 years: 2.65 [95% CI, 2.54-2.76]).

CONCLUSIONS

Younger age at T2D diagnosis is associated with a disproportionately elevated HHF risk relative to age-matched individuals without T2D.

The Impact of Blood Glucose Test Strips Reimbursement Limits on Utilization, Costs, and Health-care Utilization in British Columbia

OBJECTIVE

People living with diabetes and not using insulin may not derive clinically significant benefit from routine glucose self-monitoring. As a result, in 2015, British Columbia (BC) introduced quantity restrictions for blood glucose test strips (BGTS) coverage in public plans. We studied the impact of this policy on utilization, costs, and health-care utilization.

METHODS

We identified a cohort of adults (≥18 years old) with diabetes between 2013 and 2019. Using BC's administrative data, we studied utilization and costs among individuals with at least one PharmaCare-eligible BGTS claim. Using interrupted time-series analysis, we studied cost savings and determined the level of policy adherence. In addition, we investigated longitudinal changes in all-cause and diabetes-specific physician visits, all-cause hospitalizations, and health-care spending in the 3 to 5 years after policy implementation.

RESULTS

Over the study period, 279.7 million BGTS were eligible for PharmaCare coverage, on which the government spent $124.3 million. After policy implementation, we observed an immediate decline in average utilization and PharmaCare expenditure on BGTS, leading to an estimated $44.6 million in savings between 2015 and 2019 (95% confidence interval $16.9 to $72.3 million). We found no association between the policy's implementation and health services utilization or overall health-care spending over the long term.

CONCLUSIONS

Restricting reimbursement for BGTS in BC resulted in significant cost savings without any attendant increase in health services utilization over the subsequent 5 years. This disinvestment freed up resources that could be channeled toward other interventions.

Gestational diabetes in twin pregnancies-a pathology requiring treatment or a benign physiological adaptation?

There is level-1 evidence that screening for and treating gestational diabetes in singleton pregnancies reduce maternal and neonatal morbidity. However, similar data for gestational diabetes in twin pregnancies are currently lacking. Consequently, the current approach for the diagnosis and management of gestational diabetes in twin pregnancies is based on the same diagnostic criteria and glycemic targets used in singleton pregnancies. However, twin pregnancies have unique physiological characteristics, and many of the typical gestational diabetes-related complications are less relevant for twin pregnancies. These differences raise the question of whether the greater increase in insulin resistance observed in twin pregnancies (which is often diagnosed as diet-treated gestational diabetes) should be considered physiological and potentially beneficial in which case alternative criteria should be used for the diagnosis of gestational diabetes in twin pregnancies. In this review, we summarize the most up-to-date evidence on the epidemiology, pathophysiology, and clinical consequences of gestational diabetes in twin pregnancies and review the available data on twin-specific screening and diagnostic criteria for gestational diabetes. Although twin pregnancies are associated with a higher incidence of diet-treated gestational diabetes, diet-treated gestational diabetes in twin pregnancies is less likely to be associated with adverse outcomes and accelerated fetal growth than in singleton pregnancies and may reduce the risk for intrauterine growth restriction. In addition, there is currently no evidence that treatment of diet-treated gestational diabetes in twin pregnancies improves outcomes, whereas preliminary data suggest that strict glycemic control in such cases might increase the risk for intrauterine growth restriction. Overall, these findings provide support to the hypothesis that the greater transient increase in insulin resistance observed in twin pregnancies is merely a physiological exaggeration of the normal increase in insulin resistance observed in singleton pregnancies (that is meant to support 2 fetuses) rather than a pathology that requires treatment. These data illustrate the need to develop twin-specific screening and diagnostic criteria for gestational diabetes to avoid overdiagnosis of gestational diabetes and to reduce the risks associated with overtreatment of diet-treated gestational diabetes in twin pregnancies. Although data on twin-specific screening and diagnostic criteria are presently scarce, preliminary data suggest that the optimal screening and diagnostic criteria in twin pregnancies are higher than those currently used in singleton pregnancies.

No association between metformin initiation and incident dementia in older adults newly diagnosed with diabetes

BACKGROUND

Metformin has been suggested to reduce dementia risk; however, most epidemiologic studies have been limited by immortal time bias or confounding due to disease severity.

OBJECTIVES

To investigate the association of metformin initiation with incident dementia using strategies that mitigate these important sources of bias.

METHODS

Residents of Ontario, Canada ≥66 years newly diagnosed with diabetes from January 1, 2008 to December 31, 2017 entered this retrospective population-based cohort. To consider the indication for metformin monotherapy initiation, people with hemoglobin A1c of 6.5%-8.0% and estimated glomerular filtration rate ≥45 mL/min/1.73 m2 were selected. Using the landmark method to address immortal time bias, exposure was grouped into "metformin monotherapy initiation within 180 days after new diabetes diagnosis" or "no glucose-lowering medications within 180 days." To address disease latency, 1-year lag time was applied to the end of the 180-day landmark period. Incident dementia was defined using a validated algorithm for Alzheimer's disease and related dementias. Adjusted hazard ratios (aHR) and confidence intervals (CIs) were estimated from propensity-score weighted Cox proportional hazard models.

RESULTS

Over mean follow-up of 6.77 years from cohort entry, metformin initiation within 180 days after new diabetes diagnosis (N = 12,331; 978 events; 65,762 person-years) showed no association with dementia risk (aHR [95% CI] = 1.05 [0.96-1.15]), compared to delayed or no glucose-lowering medication initiation (N = 22,369; 1768 events; 117,415 person-years).

CONCLUSION

Early metformin initiation was not associated with incident dementia in older adults newly diagnosed with diabetes. The utility of metformin to prevent dementia was not supported.

Glycemic control and neonatal outcomes in twin pregnancies with gestational diabetes mellitus

BACKGROUND

Preliminary data suggest that strict glycemic control in twin pregnancies with gestational diabetes mellitus may not improve outcomes but might increase the risk of fetal growth restriction.

OBJECTIVE

This study aimed to investigate the association of maternal glycemic control with the risk of gestational diabetes mellitus-related complications and small for gestational age in twin pregnancies complicated by gestational diabetes mellitus.

STUDY DESIGN

This was a retrospective cohort study of all patients with a twin pregnancy complicated by gestational diabetes mellitus in a single tertiary center between 2011 and 2020, and a matched control group of patients with a twin pregnancy without gestational diabetes mellitus in a 1:3 ratio. The exposure was the level of glycemic control, described as the proportion of fasting, postprandial, and overall glucose values within target. Good glycemic control was defined as a proportion of values within target above the 50th percentile. The first coprimary outcome was a composite variable of neonatal morbidity, defined as at least 1 of the following: birthweight >90th centile for gestational age, hypoglycemia requiring treatment, jaundice requiring phototherapy, birth trauma, or admission to the neonatal intensive care unit at term. A second coprimary outcome was small for gestational age, defined as birthweight <10th centile or <3rd centile for gestational age. Associations between the level of glycemic control and the study outcomes were estimated using logistic regression analysis and were expressed as adjusted odds ratio with 95% confidence interval.

RESULTS

A total of 105 patients with gestational diabetes mellitus in a twin pregnancy met the study criteria. The overall rate of the primary outcome was 32.4% (34/105), and the overall proportion of pregnancies with a small for gestational age newborn at birth was 43.8% (46/105). Good glycemic control was not associated with a reduction in the risk of composite neonatal morbidity when compared with suboptimal glycemic control (32.1% vs 32.7%; adjusted odds ratio, 2.06 [95% confidence interval, 0.77-5.49]). However, good glycemic control was associated with higher odds of small for gestational age compared with nongestational diabetes mellitus pregnancies, especially in the subgroup of diet-treated gestational diabetes mellitus (65.5% vs 34.0%, respectively; adjusted odds ratio, 4.17 [95% confidence interval, 1.74-10.01] for small for gestational age <10th centile; and 24.1% vs 7.0%, respectively; adjusted odds ratio, 3.97 [95% confidence interval, 1.42-11.10] for small for gestational age <3rd centile). In contrast, the rate of small for gestational age in gestational diabetes mellitus pregnancies with suboptimal control was not considerably different when compared with non-gestational diabetes mellitus pregnancies. In addition, in cases of diet-treated gestational diabetes mellitus, good glycemic control was associated with a left-shift of the distribution of birthweight centiles, whereas the distribution of birthweight centiles among gestational diabetes mellitus pregnancies with suboptimal control was similar to that of nongestational diabetes mellitus pregnancies.

CONCLUSION

In patients with gestational diabetes mellitus in a twin pregnancy, good glycemic control is not associated with a reduction in the risk of gestational diabetes mellitus-related complications but may increase the risk of a small for gestational age newborn in the subgroup of patients with mild (diet-treated) gestational diabetes mellitus. These findings further question whether the gestational diabetes mellitus glycemic targets used in singleton pregnancies also apply to twin pregnancies and support the concern that applying the same diagnostic criteria and glycemic targets in twin pregnancies may result in overdiagnosis and overtreatment of gestational diabetes mellitus and potential neonatal harm.

Post-initiation predictors of discontinuation of the sodium-glucose cotransporter-2 inhibitors: A comparative cohort study from the United Kingdom

AIMS

To assess post-initiation predictors of discontinuation of sodium-glucose cotransporter-2 (SGLT2) inhibitors compared to dipeptidyl-peptidase-4 (DPP-4) inhibitors in the United Kingdom.

MATERIALS AND METHODS

We conducted a comparative population-based retrospective cohort study using primary care data from the UK Clinical Practice Research Datalink (CPRD) with linked data to hospital and death records. We included new metformin users who initiated either SGLT2 inhibitors or DPP-4 inhibitors between January 2013 and October 2019. The main outcome was treatment discontinuation, defined as the first 90-day gap after the estimated treatment end date. We used a series of extended Cox models to assess which time-dependent predictors were associated with treatment discontinuation. To test if the hazard ratio of discontinuation for each predictor was statistically different between SGLT2 and DPP-4 inhibitors, an exposure-predictor interaction term was added to each model.

RESULTS

There were 2550 new users of SGLT2 inhibitors and 8195 new users of DPP-4 inhibitors. Approximately 69% of SGLT2 inhibitor and 74% of DPP-4 inhibitor users had discontinued treatment by the end of follow-up. Occurrence of fractures after treatment initiation was a significant predictor of discontinuation of SGLT2 inhibitors (hazard ratio [HR] 4.13, 95% confidence interval [CI] 2.12-8.06) but not DPP-4 inhibitors (HR 0.93, 95% CI 0.79-1.11). The rate of treatment discontinuation was significantly higher for those with low estimated glomerular filtration rate and minimal contact with the healthcare system. Efficacy endpoints, such as heart failure and glycated haemoglobin level, were not associated with treatment discontinuation.

CONCLUSIONS

Our findings reflect some discrepancy between the available evidence and prescribing behaviour for SGLT2 inhibitors.

The Glucose Challenge Test in Pregnancy Identifies Future Risk of Diabetes

CONTEXT

Women with gestational diabetes (GDM) have an increased future risk of type 2 diabetes but, in practice, their recommended postpartum glucose tolerance testing is often missed or substituted with measurement of A1c instead.

OBJECTIVE

We hypothesized that the antenatal screening glucose challenge test (GCT) should predict future diabetes risk and, if so, would have thresholds that identify the same degree of risk as the diagnosis of prediabetes on postpartum measurement of A1c.

METHODS

With population-based administrative databases, we identified all women in Ontario, Canada, who had a GCT in pregnancy with delivery between January 2007 and December 2017, followed by measurement of A1c and fasting glucose within 2 years postpartum (n = 141 858, including 19 034 with GDM). Women were followed over a median of 3.5 years for the development of diabetes.

RESULTS

Under the assumption of a linear exposure effect, the 1-hour post-challenge glucose concentration on the GCT was associated with an increased likelihood of developing diabetes (hazard ratio 1.39; 95% CI, 1.38-1.40). A GCT threshold of 8.0 mmol/L predicted the same 5-year risk of diabetes (6.0%; 95% CI, 5.8-6.2) as postpartum A1c 5.7% (identifying prediabetes). Moreover, in women with GDM, a GCT threshold of 9.8 mmol/L equaled prediabetes on postpartum A1c in predicting a 5-year risk of diabetes of 16.5% (14.8-18.2).

CONCLUSION

The GCT offers predictive capacity for future diabetes in pregnant women. In women with GDM, this insight could identify those at highest risk of diabetes, toward whom postpartum screening efforts should be most strongly directed.

Dealing With Nonproportional Hazards in Coronary Revascularisation Studies

The Cox proportional hazards model is one of the most popular statistical tools to model time to event outcomes without the need for specifying the hazards or survival time distributions. The Cox model requires that the ratio of the hazards of the occurrence of the outcome for any 2 individuals remains constant during the entire follow-up. Studies comparing coronary revascularisation strategies, however, might be prone to violations of proportionality by the crossing of the hazard functions over time. Early increases in the risk of cardiovascular outcomes are commonly observed when comparing coronary artery bypass grafting vs percutaneous coronary intervention, whereas decreased risk might be observed later during the follow-up. The same is valid for comparisons between invasive vs conservative coronary revascularisation strategies. In these situations, the statistical power of the Cox model is reduced, and hazard ratios might not be an informative summary measure of treatment effect. In this article, we discuss methods to identify and account for nonproportionality. We illustrate the use of these methods in a case study based on reconstructed data from a coronary revascularisation clinical trial. And finally, we review the cardiovascular literature to estimate how the proportionality assumption has been reported in coronary revascularisation studies recently.

Association of sulfonylureas with the risk of dementia: A population-based cohort study

BACKGROUND

Sulfonylureas are oral glucose-lowering medications positioned as a second-line therapy for type 2 diabetes. Evidence relating them to cognitive decline has been mixed. The objective was to determine whether sulfonylurea use was associated with a differential risk of dementia compared with dipeptidyl peptidase-4 (DPP4) inhibitor use.

METHODS

Using administrative data from residents in Ontario, Canada, adults aged ≥66 years who were new users of a sulfonylurea or a DPP4 inhibitor from June 14, 2011, to March 31, 2021 entered this population-based retrospective cohort study. Dementia was ascertained using a validated algorithm for Alzheimer's disease and related dementias. Propensity-score weighted Cox proportional hazards models were used to obtain adjusted hazard ratios (aHR) and confidence intervals (CI) for time to incident dementia. The observation window started at 1 year after cohort entry to mitigate protopathic bias due to delayed diagnosis. The primary analysis used an intention-to-treat exposure definition. A separate propensity-score weighted analysis was conducted to explore within-class differences in dementia risk among sulfonylurea new users selected from the primary cohort.

RESULTS

Among 107,806 DPP4 inhibitor new users and 37,030 sulfonylurea new users, sulfonylureas compared with DPP4 inhibitors were associated with a higher risk of dementia (18.4/1000 person-years; aHR [95% CI] = 1.09 [1.04-1.15]) over a mean follow-up of 4.82 years from cohort entry. Glyburide compared to gliclazide exhibited a higher dementia risk (aHR [95% CI] = 1.17 [1.03-1.32]).

CONCLUSION

New use of a sulfonylurea especially glyburide was associated with a higher dementia risk compared with new use of a DPP4 inhibitor in older adults with diabetes.

Ethnic differences in the association between age at diagnosis of diabetes and the risk of cardiovascular complications: a population-based cohort study

BACKGROUND

We examined ethnic differences in the association between age at diagnosis of diabetes and the risk of cardiovascular complications.

METHODS

We conducted a population-based cohort study in Ontario, Canada among individuals with diabetes and matched individuals without diabetes (2002-18). We fit Cox proportional hazards models to determine the associations of age at diagnosis and ethnicity (Chinese, South Asian, general population) with cardiovascular complications. We tested for an interaction between age at diagnosis and ethnicity.

RESULTS

There were 453,433 individuals with diabetes (49.7% women) and 453,433 matches. There was a significant interaction between age at diagnosis and ethnicity (P < 0.0001). Young-onset diabetes (age at diagnosis < 40) was associated with higher cardiovascular risk [hazard ratios: Chinese 4.25 (3.05-5.91), South Asian: 3.82 (3.19-4.57), General: 3.46 (3.26-3.66)] than usual-onset diabetes [age at diagnosis ≥ 40 years; Chinese: 2.22 (2.04-2.66), South Asian: 2.43 (2.22-2.66), General: 1.83 (1.81-1.86)] versus ethnicity-matched individuals. Among those with young-onset diabetes, Chinese ethnicity was associated with lower overall cardiovascular [0.44 (0.32-0.61)] but similar stroke risks versus the general population; while South Asian ethnicity was associated with lower overall cardiovascular [0.75 (0.64-0.89)] but similar coronary artery disease risks versus the general population. In usual-onset diabetes, Chinese ethnicity was associated with lower cardiovascular risk [0.44 (0.42-0.46)], while South Asian ethnicity was associated with lower cardiovascular [0.90 (0.86-0.95)] and higher coronary artery disease [1.08 (1.01-1.15)] risks versus the general population.

CONCLUSIONS

There are important ethnic differences in the association between age at diagnosis and risk of cardiovascular complications.

Association of prior outpatient diabetes screening with cardiovascular events and mortality among people with incident diabetes: a population-based cohort study

BACKGROUND

Outcomes of diabetes screening in contemporary, multi-ethnic populations are unknown. We examined the association of prior outpatient diabetes screening with the risks of cardiovascular events and mortality in Ontario, Canada.

METHODS

We conducted a population-based cohort study using administrative databases among adults aged ≥ 20 years with incident diabetes diagnosed during 2014-2016. The exposure was outpatient diabetes screening performed within 3 years prior to diabetes diagnosis. The co-primary outcomes were (1) a composite of all-cause mortality and hospitalization for myocardial infarction, stroke, coronary revascularization, and (2) all-cause mortality (followed up until 2018). We calculated standardized rates of each outcome and conducted cause-specific hazard modelling to determine the adjusted hazard ratio (HR) of the outcomes, adjusting for prespecified confounders and accounting for the competing risk of death.

RESULTS

We included 178,753 Ontarians with incident diabetes (70.2% previously screened). Individuals receiving prior screening were older (58.3 versus 53.4 years) and more likely to be women (49.6% versus 40.0%) than previously unscreened individuals. Individuals receiving prior screening had relatively lower standardized event rates than those without prior screening across all outcomes (composite: 12.8 versus 18.1, mortality: 8.2 versus 11.1 per 1000 patient-years). After multivariable adjustment, prior screening was associated with 34% and 32% lower risks of the composite (HR 0.66, 0.63-0.69) and mortality (0.68, 0.64-0.72) outcomes. Among those receiving prior screening, a result in the prediabetes range was associated with lower risks of the composite (0.82, 0.77-0.88) and mortality (0.71, 0.66-0.78) outcomes than a result in the normoglycemic range.

CONCLUSIONS

Previously screened individuals with diabetes had lower risks of cardiovascular events and mortality versus previously unscreened individuals. Better risk assessment tools are needed to support wider and more appropriate uptake of diabetes screening, especially among young adults.

Prediction of birthweight and risk of macrosomia in pregnancies complicated by diabetes

BACKGROUND

Antenatal detection of accelerated fetal growth and macrosomia in pregnancies complicated by diabetes mellitus is important for patient counseling and management. Sonographic fetal weight estimation is the most commonly used tool to predict birthweight and macrosomia. However, the predictive accuracy of sonographic fetal weight estimation for these outcomes is limited. In addition, an up-to-date sonographic fetal weight estimation is often unavailable before birth. This may result in a failure to identify macrosomia, especially in pregnancies complicated by diabetes mellitus where care providers might underestimate fetal growth rate. Therefore, there is a need for better tools to detect and alert care providers to the potential risk of accelerated fetal growth and macrosomia.

OBJECTIVE

This study aimed to develop and validate prediction models for birthweight and macrosomia in pregnancies complicated by diabetes mellitus.

STUDY DESIGN

This was a completed retrospective cohort study of all patients with a singleton live birth at ≥36 weeks of gestation complicated by preexisting or gestational diabetes mellitus observed at a single tertiary center between January 2011 and May 2022. Candidate predictors included maternal age, parity, type of diabetes mellitus, information from the most recent sonographic fetal weight estimation (including estimated fetal weight, abdominal circumference z score, head circumference-to-abdomen circumference z score ratio, and amniotic fluid), fetal sex, and the interval between ultrasound examination and birth. The study outcomes were macrosomia (defined as birthweights >4000 and >4500 g), large for gestational age (defined as a birthweight >90th percentile for gestational age), and birthweight (in grams). Multivariable logistic regression models were used to estimate the probability of dichotomous outcomes, and multivariable linear regression models were used to estimate birthweight. Model discrimination and predictive accuracy were calculated. Internal validation was performed using the bootstrap resampling technique.

RESULTS

A total of 2465 patients met the study criteria. Most patients had gestational diabetes mellitus (90%), 6% of patients had type 2 diabetes mellitus, and 4% of patients had type 1 diabetes mellitus. The overall proportions of infants with birthweights >4000 g, >4500 g, and >90th percentile for gestational age were 8%, 1%, and 12%, respectively. The most contributory predictor variables were estimated fetal weight, abdominal circumference z score, ultrasound examination to birth interval, and type of diabetes mellitus. The models for the 3 dichotomous outcomes had high discriminative accuracy (area under the curve receiver operating characteristic curve, 0.929-0.979), which was higher than that achieved with estimated fetal weight alone (area under the curve receiver operating characteristic curve, 0.880-0.931). The predictive accuracy of the models had high sensitivity (87%-100%), specificity (84%-92%), and negative predictive values (84%-92%). The predictive accuracy of the model for birthweight had low systematic and random errors (0.6% and 7.5%, respectively), which were considerably smaller than the corresponding errors achieved with estimated fetal weight alone (-5.9% and 10.8%, respectively). The proportions of estimates within 5%, 10%, and 15% of the actual birthweight were high (52.3%, 82.9%, and 94.9%, respectively).

CONCLUSION

The prediction models developed in the current study were associated with greater predictive accuracy for macrosomia, large for gestational age, and birthweight than the current standard of care that includes estimated fetal weight alone. These models may assist care providers in counseling patients regarding the optimal timing and mode of delivery.

Prevalent diabetes and long-term cardiovascular outcomes in adult sepsis survivors: a population-based cohort study

BACKGROUND

Sepsis survivors are at elevated risk for cardiovascular disease during long-term follow-up. Whether diabetes influences cardiovascular risk after sepsis survival remains unknown. We sought to describe the association of diabetes with long-term cardiovascular outcomes in adult sepsis survivors.

METHODS

Population-based cohort study in the province of Ontario, Canada (2008-2017). Adult survivors of a first sepsis-associated hospitalization, without pre-existing cardiovascular disease, were included. Main exposure was pre-existing diabetes (any type). The primary outcome was the composite of myocardial infarction, stroke, and cardiovascular death. Patients were followed up to 5 years from discharge date until outcome occurrence or end of study period (March 2018). We used propensity score matching (i.e., 1:1 to patients with sepsis but no pre-existing diabetes) to adjust for measured confounding at baseline. Cause-specific Cox proportional hazards models with robust standard errors were used to estimate hazard ratios (HR) alongside 95% confidence intervals (CI). A main secondary analysis evaluated the modification of the association between sepsis and cardiovascular disease by pre-existing diabetes.

RESULTS

78,638 patients with pre-existing diabetes who had a sepsis-associated hospitalization were matched to patients hospitalized for sepsis but without diabetes. Mean age of patients was 71 years, and 55% were female. Median duration from diabetes diagnosis was 9.8 years; mean HbA1c was 7.1%. Adult sepsis survivors with pre-existing diabetes experienced a higher hazard of major cardiovascular disease (HR 1.25; 95% CI 1.22-1.29)-including myocardial infarction (HR 1.40; 95% CI 1.34-1.47) and stroke (HR 1.24; 95% CI 1.18-1.29)-during long-term follow-up compared to sepsis survivors without diabetes. Pre-existing diabetes modified the association between sepsis and cardiovascular disease (risk difference: 2.3%; 95% CI 2.0-2.6 and risk difference: 1.8%; 95% CI 1.6-2.0 for the effect of sepsis-compared to no sepsis-among patients with and without diabetes, respectively).

CONCLUSIONS

Sepsis survivors with pre-existing diabetes experience a higher long-term hazard of major cardiovascular events when compared to sepsis survivors without diabetes. Compared to patients without sepsis, the absolute risk increase of cardiovascular events after sepsis is higher in patients with diabetes (i.e., diabetes intensified the higher cardiovascular risk induced by sepsis).

Cytochrome P450-soluble epoxide hydrolase derived linoleic acid oxylipins and cognitive performance in type 2 diabetes

Type 2 diabetes mellitus (T2DM) increases the risk of cognitive decline and dementia. Disruptions in the cytochrome P450-soluble epoxide hydrolase (CYP450-sEH) pathway have been reported in T2DM, obesity and cognitive impairment. We examine linoleic acid (LA)-derived CYP450-sEH oxylipins and cognition in T2DM and explore potential differences between obese and nonobese individuals. The study included 51 obese and 57 nonobese participants (mean age 63.0 ± 9.9, 49% women) with T2DM. Executive function was assessed using the Stroop Color-Word Interference Test, FAS-Verbal Fluency Test, Digit Symbol Substitution Test, and Trails Making Test-Part B. Verbal memory was assessed using the California Verbal Learning Test, second Edition. Four LA-derived oxylipins were analyzed by ultra-high-pressure-LC/MS, and the 12,13-dihydroxyoctadecamonoenoic acid (12,13-DiHOME) considered the main species of interest. Models controlled for age, sex, BMI, glycosylated hemoglobin A1c, diabetes duration, depression, hypertension, and education. The sEH-derived 12,13-DiHOME was associated with poorer executive function scores (F1,98 = 7.513, P = 0.007). The CYP450-derived 12(13)-epoxyoctadecamonoenoic acid (12(13)-EpOME) was associated with poorer executive function and verbal memory scores (F1,98 = 7.222, P = 0.008 and F1,98 = 4.621, P = 0.034, respectively). There were interactions between obesity and the 12,13-DiHOME/12(13)-EpOME ratio (F1,97 = 5.498, P = 0.021) and between obesity and 9(10)-epoxyoctadecamonoenoic acid (9(10)-EpOME) concentrations (F1,97 = 4.126, P = 0.045), predicting executive function such that relationships were stronger in obese individuals. These findings suggest that the CYP450-sEH pathway as a potential therapeutic target for cognitive decline in T2DM. For some markers, relationships may be obesity dependent.

Association of Beta-Blocker Therapy With Cardiovascular Outcomes in Patients With Stable Ischemic Heart Disease

BACKGROUND

Previous studies have failed to show a cardioprotective benefit of beta-blockers in patients with stable coronary artery disease (CAD).

OBJECTIVES

This study sought to determine the association between beta-blockers and cardiovascular events in patients with stable CAD using a new user design.

METHODS

All patients aged >66 years undergoing elective coronary angiography in Ontario, Canada, from 2009 to 2019 with diagnosed obstructive CAD were included. Exclusion criteria included heart failure or a recent myocardial infarction, as well as having a beta-blocker prescription claim in the previous year. Beta-blocker use was defined as having at least 1 beta-blocker prescription claim in the 90 days preceding or after the index coronary angiography. The main outcome was a composite of all-cause mortality and hospitalization for heart failure or myocardial infarction. Inverse probability of treatment weighting using the propensity score was used to account for confounding.

RESULTS

This study included 28,039 patients (mean age: 73.0 ± 5.6 years; 66.2% male), and 12,695 of those (45.3%) were newly prescribed beta-blockers. The 5-year risks of the primary outcome were 14.3% in the beta-blocker group and 16.1% in the no beta-blocker group (absolute risk reduction: -1.8%; 95% CI: -2.8 to -0.8; HR: 0.92; 95% CI: 0.86-0.98; P = 0.006). This result was driven by reductions in myocardial infarction hospitalization (cause-specific HR: 0.87; 95% CI: 0.77-0.99; P = 0.031), whereas no differences were observed in all-cause death or heart failure hospitalization.

CONCLUSIONS

In patients with angiographically documented stable CAD without heart failure or a recent myocardial infarction, beta-blockers were associated with a small but significant reduction in cardiovascular events at 5 years.

Incidence of Heart Failure Related to Co-Occurrence of Gestational Hypertensive Disorders and Gestational Diabetes

BACKGROUND

The extent to which their co-occurrence of gestational hypertensive disorders (GHTD) and gestational diabetes mellitus (GDM) influences heart failure (HF) risk is unclear.

OBJECTIVES

The purpose of this study was to characterize the risk of HF related to concomitant GHTD and GDM.

METHODS

We conducted a population-based cohort study using the Ministry of Health and Long-Term Care of Ontario (Canada) health care administrative databases. We included women with a livebirth singleton delivery between July 1, 2007, and March 31, 2018, and excluded those with prepregnancy diabetes, hypertension, HF, or coronary artery disease. GDM, GHTD, peripartum cardiomyopathy (at index pregnancy) were identified using diagnosis coding. Incident HF was assessed from index pregnancy until March 31, 2020. We estimated associations of GDM and/or GHTD with peripartum cardiomyopathy and incident HF.

RESULTS

Among 885,873 women (mean age: 30 years, 54,015 with isolated GDM, 43,750 with isolated GHTD, 4,960 with GDM and GHTD), there were 489 HF events over 8 years. Compared to no-GDM and no-GHTD, isolated GDM (adjusted hazard ratio [aHR]: 1.44; 95% CI: 1.02-2.04) and isolated GHTD (aHR: 1.65; 95% CI: 1.17-2.31) were associated with a higher risk of incident HF. The co-occurrence of GDM and GHTD was associated with a higher HF risk (aHR: 2.64; 95% CI: 1.24-5.61). GDM and GHTD increased the risk of peripartum cardiomyopathy (adjusted risk ratio [aRR]: 7.30; 95% CI: 6.92-7.58), similarly to isolated GHTD (aRR: 7.40; 95% CI: 7.23-7.58).

CONCLUSIONS

The co-occurrence of GDM and GHTD was associated with a significantly high risk of incident HF.

Erratum. Association Between Obesity and Chronic Kidney Disease: Multivariable Mendelian Randomization Analysis and Observational Data From a Bariatric Surgery Cohort. Diabetes 2023;72:496-510

In Table 2 of the article cited above, the univariable MR analyses for microalbuminuria were erroneously cited as inverse variance weighted analyses. The row headings in Table 2 have been revised to show the correct analyses performed: MR-Egger, weighted median and mode, and simple mode analyses. In Fig. 3, the confidence intervals were erroneously plotted as error bars. Fig. 3 has been updated with the correct confidence intervals from the text. The revised online version of the article can be accessed at https://doi.org/10.2337/db22-0696.

Effect of Free Medicine Distribution on Health Care Costs in Canada Over 3 Years: A Secondary Analysis of the CLEAN Meds Randomized Clinical Trial

Importance

Few interventions are proven to reduce total health care costs, and addressing cost-related nonadherence has the potential to do so.

Objective

To determine the effect of eliminating out-of-pocket medication fees on total health care costs.

Design, Setting, and Participants

This secondary analysis of a multicenter randomized clinical trial using a prespecified outcome took place across 9 primary care sites in Ontario, Canada (6 in Toronto and 3 in rural areas), where health care services are generally publicly funded. Adult patients (≥18 years old) reporting cost-related nonadherence to medicines in the past 12 months were recruited between June 1, 2016, and April 28, 2017, and followed up until April 28, 2020. Data analysis was completed in 2021.

Interventions

Access to a comprehensive list of 128 medicines commonly prescribed in ambulatory care with no out-of-pocket costs for 3 years vs usual medicine access.

Main Outcome and Measures

Total publicly funded health care costs over 3 years, including costs of hospitalizations. Health care costs were determined using administrative data from Ontario's single-payer health care system, and all costs are reported in Canadian dollars with adjustments for inflation.

Results

A total of 747 participants from 9 primary care sites were included in the analysis (mean [SD] age, 51 [14] years; 421 [56.4%] female). Free medicine distribution was associated with a lower median total health care spending over 3 years of $1641 (95% CI, $454-$2792; P = .006). Mean total spending was $4465 (95% CI, -$944 to $9874) lower over the 3-year period.

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, eliminating out-of-pocket medication expenses for patients with cost-related nonadherence in primary care was associated with lower health care spending over 3 years. These findings suggest that eliminating out-of-pocket medication costs for patients could reduce overall costs of health care.

Trial Registration

ClinicalTrials.gov Identifier: NCT02744963.

The association between immigration status and the development of type 2 diabetes in women with a prior diagnosis of gestational diabetes: a population-based study

AIMS

To examine the influence of immigration status and region of origin on the risk of type 2 diabetes in women with prior gestational diabetes (GDM).

METHODS

This retrospective population-based cohort study included women with gestational diabetes (GDM) aged 16 to 50 years in Ontario, Canada who gave birth between 2006-2014. We compared the incidence of type 2 diabetes after delivery between long-term residents and immigrants - overall, by time since immigration, and by region of origin - using Cox regression adjusted for age, year, neighbourhood income, rurality, infant birth weight, and presence of hypertensive disorders of pregnancy (HDP).

RESULTS

Among 38,515 women with prior GDM (42% immigrants), immigrants had a significantly higher risk of type 2 diabetes compared to long-term residents [adjusted hazard ratio (HR) 1.19, 95% confidence interval (CI) 1.13- 1.26], with no meaningful difference based on time since immigration. The highest adjusted relative risks of type 2 diabetes compared to long-term residents were found for immigrants from Sub-Saharan Africa (HR 1.63, 95% CI 1.40-1.90), Latin America/Caribbean (HR 1.44, 95% CI 1.28-1.62) and South Asia (HR 1.34, 95% CI 1.25-1.44).

CONCLUSIONS

Immigration is associated with a significantly higher risk of type 2 diabetes after GDM, particularly for women from certain low- and middle-income countries. Diabetes prevention strategies will need to consider the unique needs of immigrants from these regions.

Team-Based Diabetes Care in Ontario and Hong Kong: a Comparative Review

PURPOSE OF REVIEW

There are gaps in implementing and accessing team-based diabetes care. We reviewed and compared how team-based diabetes care was implemented in the primary care contexts of Ontario and Hong Kong.

RECENT FINDINGS

Ontario's Diabetes Education Programs (DEPs) were scaled-up incrementally. Hong Kong's Multidisciplinary Risk Assessment and Management Program for Diabetes Mellitus (RAMP-DM) evolved from a research-driven quality improvement program. Each jurisdiction had a mixture of non-team and team-based primary care with variable accessibility. Referral procedures, follow-up processes, and financing models varied. DEPs used a flexible approach, while the RAMP-DM used structured assessment for quality assurance. Each approach depended on adequate infrastructure, processes, and staff. Diabetes care is most accessible and functional when integrated team-based services are automatically initiated upon diabetes diagnosis within a strong primary care system, ideally linked to a register with supports including specialist care. Structured assessment and risk stratification are the basis of a well-studied, evidence-based approach for achieving the standards of team-based diabetes care, although flexibility in care delivery may be needed to meet the unique needs of some individuals. Policymakers and funders should ensure investment in skilled health professionals, infrastructure, and processes to improve care quality.

Association Between Obesity and Chronic Kidney Disease: Multivariable Mendelian Randomization Analysis and Observational Data From a Bariatric Surgery Cohort

Obesity is postulated to independently increase chronic kidney disease (CKD), even after adjusting for type 2 diabetes (T2D) and hypertension. Dysglycemia below T2D thresholds, frequently seen with obesity, also increases CKD risk. Whether obesity increases CKD independent of dysglycemia and hypertension is unknown and likely influences the optimal weight loss (WL) needed to reduce CKD. T2D remission rates plateau with 20-25% WL after bariatric surgery (BS), but further WL increases normoglycemia and normotension. We undertook bidirectional inverse variance weighted Mendelian randomization (IVWMR) to investigate potential independent causal associations between increased BMI and estimated glomerular filtration rate (eGFR) in CKD (CKDeGFR) (<60 mL/min/1.73 m2) and microalbuminuria (MA). In 5,337 BS patients, we assessed whether WL influences >50% decline in eGFR (primary outcome) or CKD hospitalization (secondary outcome), using <20% WL as a comparator. IVWMR results suggest that increased BMI increases CKDeGFR (b = 0.13, P = 1.64 × 10-4; odds ratio [OR] 1.14 [95% CI 1.07, 1.23]) and MA (b = 0.25; P = 2.14 × 10-4; OR 1.29 [1.13, 1.48]). After adjusting for hypertension and fasting glucose, increased BMI did not significantly increase CKDeGFR (b = -0.02; P = 0.72; OR 0.98 [0.87, 1.1]) or MA (b = 0.19; P = 0.08; OR 1.21 [0.98, 1.51]). Post-BS WL significantly reduced the primary outcome with 30 to <40% WL (hazard ratio [HR] 0.53 [95% CI 0.32, 0.87]) but not 20 to <30% WL (HR 0.72 [0.44, 1.2]) and ≥40% WL (HR 0.73 [0.41, 1.30]). For CKD hospitalization, progressive reduction was seen with increased WL, which was significant for 30 to <40% WL (HR 0.37 [0.17, 0.82]) and ≥40% WL (HR 0.24 [0.07, 0.89]) but not 20 to <30% WL (HR 0.60 [0.29, 1.23]). The data suggest that obesity is likely not an independent cause of CKD. WL thresholds previously associated with normotension and normoglycemia, likely causal mediators, may reduce CKD after BS.

Growing Income-Related Disparities in Cardiovascular Hospitalizations Among People With Diabetes, 1995-2019: A Population-Based Study

OBJECTIVE

Cardiovascular risk reduction is an important focus in the management of people with diabetes. Although event rates have been declining over the long term, they have been observed to plateau or reverse in recent years. Furthermore, the impact of income-related disparities in cardiovascular events is unknown. The objective of this study is to evaluate age-, sex-, and income-related trends in cardiovascular hospitalization rates among people with diagnosed diabetes.

RESEARCH DESIGN AND METHODS

We calculated rates of hospitalization for acute myocardial infarction, stroke, heart failure, and lower-extremity amputation in annual cohorts of the entire population of Ontario, Canada, with diagnosed diabetes, from 1995 to 2019. Event rates were stratified by age, sex, and income level.

RESULTS

We studied nearly 1.7 million people with diabetes. The rate of acute myocardial infarction declined throughout the 25-year study period (P < 0.0001), such that the rate in 2019 was less than half the rate in 1995. Rates of stroke (P < 0.0001), heart failure (P < 0.0001), and amputation (P < 0.0001) also changed over time, but hospitalization rates stabilized through the 2010s. This apparent stabilization concealed a growing income-related disparity: wealthier patients showed continued declines in rates of these outcomes during the decade, whereas rates for lower-income patients increased (P for interaction < 0.0001 for all four outcomes).

CONCLUSIONS

During a quarter-century of follow-up, cardiovascular hospitalization rates among people with diabetes fell. However, the apparent stabilization in rates of stroke, heart failure, and amputation in recent years masks the fact that rates have risen for lower-income individuals.

Factors influencing influenza, pneumococcal and shingles vaccine uptake and refusal in older adults: a population-based cross-sectional study in England

OBJECTIVES

Uptake of influenza, pneumococcal and shingles vaccines in older adults vary across regions and socioeconomic backgrounds. In this study, we study the coverage and factors associated with vaccination uptake, as well as refusal in the unvaccinated population and their associations with ethnicity, deprivation, household size and health conditions.

DESIGN, SETTING AND PARTICIPANTS

This is a cross-sectional study of adults aged 65 years or older in England, using a large primary care database. Associations of vaccine uptake and refusal in the unvaccinated with ethnicity, deprivation, household size and health conditions were modelled using multivariable logistic regression.

OUTCOME MEASURE

Influenza, pneumococcal and shingles vaccine uptake and refusal (in the unvaccinated).

RESULTS

This study included 2 054 463 patients from 1318 general practices. 1 711 465 (83.3%) received at least one influenza vaccine, 1 391 228 (67.7%) pneumococcal vaccine and 690 783 (53.4%) shingles vaccine. Compared with White ethnicity, influenza vaccine uptake was lower in Chinese (OR 0.49; 95% CI 0.45 to 0.53), 'Other ethnic' groups (0.63; 95% CI 0.60 to 0.65), black Caribbean (0.68; 95% CI 0.64 to 0.71) and black African (0.72; 95% CI 0.68 to 0.77). There was generally lower vaccination uptake among more deprived individuals, people living in larger household sizes (three or more persons) and those with fewer health conditions. Among those who were unvaccinated, higher odds of refusal were associated with the black Caribbean ethnic group and marginally with increased deprivation, but not associated with higher refusal in those living in large households or those with lesser health conditions.

CONCLUSION

Certain ethnic minority groups, deprived populations, large households and 'healthier' individuals were less likely to receive a vaccine, although higher refusal was only associated with ethnicity and deprivation but not larger households nor healthier individuals. Understanding these may inform tailored public health messaging to different communities for equitable implementation of vaccination programmes.

Ethnic disparities in COVID-19 outcomes: a multinational cohort study of 20 million individuals from England and Canada

BACKGROUND

Heterogeneous studies have demonstrated ethnic inequalities in the risk of SARS-CoV-2 infection and adverse COVID-19 outcomes. This study evaluates the association between ethnicity and COVID-19 outcomes in two large population-based cohorts from England and Canada and investigates potential explanatory factors for ethnic patterning of severe outcomes.

METHODS

We identified adults aged 18 to 99 years in the QResearch primary care (England) and Ontario (Canada) healthcare administrative population-based datasets (start of follow-up: 24th and 25th Jan 2020 in England and Canada, respectively; end of follow-up: 31st Oct and 30th Sept 2020, respectively). We harmonised the definitions and the design of two cohorts to investigate associations between ethnicity and COVID-19-related death, hospitalisation, and intensive care (ICU) admission, adjusted for confounders, and combined the estimates obtained from survival analyses. We calculated the 'percentage of excess risk mediated' by these risk factors in the QResearch cohort.

RESULTS

There were 9.83 million adults in the QResearch cohort (11,597 deaths; 21,917 hospitalisations; 2932 ICU admissions) and 10.27 million adults in the Ontario cohort (951 deaths; 5132 hospitalisations; 1191 ICU admissions). Compared to the general population, pooled random-effects estimates showed that South Asian ethnicity was associated with an increased risk of COVID-19 death (hazard ratio: 1.63, 95% CI: 1.09-2.44), hospitalisation (1.53; 1.32-1.76), and ICU admission (1.67; 1.23-2.28). Associations with ethnic groups were consistent across levels of deprivation. In QResearch, sociodemographic, lifestyle, and clinical factors accounted for 42.9% (South Asian) and 39.4% (Black) of the excess risk of COVID-19 death.

CONCLUSION

International population-level analyses demonstrate clear ethnic inequalities in COVID-19 risks. Policymakers should be cognisant of the increased risks in some ethnic populations and design equitable health policy as the pandemic continues.

Predicting left main stenosis in stable ischemic heart disease using logistic regression and boosted trees

BACKGROUND

The ISCHEMIA trial showed similar cardiovascular outcomes of an initial conservative strategy as compared with invasive management in patients with stable ischemic heart disease without left main stenosis. We aim to assess the feasibility of predicting significant left main stenosis using extensive clinical, laboratory and non-invasive tests data.

METHODS

All adult patients who had stress testing prior to undergoing an elective coronary angiography for stable ischemic heart disease in Ontario, Canada, between April 2010 and March 2019, were included. Candidate predictors included comprehensive demographics, comorbidities, laboratory tests, and cardiac stress test data. The outcome was stenosis of 50% or greater in the left main coronary artery. A traditional model (logistic regression) and a machine learning algorithm (boosted trees) were used to build prediction models.

RESULTS

Among 150,423 patients included (mean age: 64.2 ± 10.6 years; 64.1% males), there were 9,225 (6.1%) with left main stenosis. The final logistic regression model included 24 predictors and 3 interactions, had an optimism-adjusted c-statistic of 0.72 and adequate calibration (optimism-adjusted Integrated Calibration Index 0.0044). These results were consistent in subgroups of males and females, diabetes and non-diabetes, and extent of ischemia. The boosted tree algorithm had similar accuracy, also resulting in a c-statistic of 0.72 and adequate calibration (Integrated Calibration Index 0.0054).

CONCLUSIONS

In this large population-based study of patients with stable ischemic heart disease using extensive clinical data, only modest prediction of left main coronary artery disease was possible with traditional and machine learning modelling techniques.

Validation of Algorithms to Identify Gestational Diabetes From Population-level Health-care Administrative Data

OBJECTIVES

Our aim in this study was to determine the test characteristics of algorithms using hospitalization and physician claims data to predict gestational diabetes (GDM).

METHODS

Using population-level health-care administrative data, we identified all pregnant women in Ontario in 2019. The presence of GDM was determined based on glucose screening laboratory results. Algorithms using hospitalization records and/or physician claims were tested against this "gold standard." The selected algorithm was applied to administrative data records from 1999 to 2019 to determine GDM prevalence in each year.

RESULTS

Identifying GDM based on either a diabetes mellitus code on the delivery hospitalization record, OR at least 1 physician claim with a diabetes diagnosis code with a 90-day lookback before delivery yielded a sensitivity of 95.9%, a specificity of 99.2% and a positive predictive value of 87.6%. The prevalence of GDM increased from 4.2% of pregnancies in 1999 to 12.0% in 2019.

CONCLUSION

Algorithms using hospitalization or physician claims administrative data can accurately identify GDM.

Associations Among Biomarkers of Inflammation, Tubular Injury and Lipid Metabolism With Gestational Diabetes Mellitus Status, Microalbuminuria and Retinopathy in the Microalbuminuria and Retinopathy in Gestational Diabetes Study

OBJECTIVES

Pregnancy may be complicated by gestational diabetes mellitus (GDM) and/or microvascular complications like albuminuria, retinopathy and pre-eclampsia. In this study we aimed to identify whether mechanistic pathways associated with microvascular complications are active in pregnant women with GDM or microvascular disease.

METHODS

Urinary albumin excretion and biomarkers of inflammation, lipoprotein metabolism and tubular injury were quantified in 355 pregnant women with and without GDM. Participants underwent fundus photography graded for retinopathy. Adjusted associations between individual biomarkers and each outcome variable of interest, including GDM status, albuminuria and retinopathy, were performed using logistic regression.

RESULTS

After adjusting for age, systolic blood pressure, body mass index and ethnicity, significant associations between GDM status and apolipoprotein A1, interleukin (IL)-6, IL-8, soluble tumour necrosis factor receptor-I and -II (sTNFR-I and -II), vascular endothelial growth factor and von Willebrand factor were observed. Increased high-sensitivity C-reactive protein (hsCRP) and sTNFR-II were associated with higher levels of albuminuria. hsCRP and previous GDM were associated with retinopathy.

CONCLUSION

Mechanistic pathways associated with microvascular complications appear to be active in pregnant women with GDM or microvascular disease.

The association between offspring birthweight and future risk of maternal diabetes: A population-based study

AIMS

As an indicator of maternal cardiometabolic health, newborn birthweight may be an important predictor of maternal type 2 diabetes mellitus (diabetes). We evaluated the relation between offspring birthweight and onset of maternal diabetes after pregnancy.

METHODS

This retrospective cohort study used linked population-based health databases from Ontario, Canada. We included women aged 16-50 years without pre-pregnancy diabetes, and who had a live birth between 2006 and 2014. We used Cox proportional hazard regression to evaluate the association between age- and sex-standardized offspring birthweight percentile categories and incident maternal diabetes, while adjusting for maternal age, parity, year, ethnicity, gestational diabetes (GDM) and hypertensive disorders of pregnancy (HDP). Results were further stratified by the presence of GDM in the index pregnancy.

RESULTS

Of 893,777 eligible participants, 14,329 (1.6%) women were diagnosed with diabetes over a median (IQR) of 4.4 (1.5-7.4) years of follow-up. There was a continuous positive relation between newborn birthweight above the 75th percentile and maternal diabetes. Relative to a birthweight between the 50th and 74.9th percentiles, women whose newborn had a birthweight between the 97th and 100th percentiles had an adjusted hazards ratio (aHR) of diabetes of 2.30 (95% CI 2.16-2.46), including an aHR of 2.01 (95% CI 1.83-2.21) among those with GDM, and 2.59 (2.36-2.84) in those without GDM.

CONCLUSIONS

A higher offspring birthweight signals an increased risk of maternal diabetes, offering another potentially useful way to identify women especially predisposed to diabetes.

Association of Sodium-Glucose Cotransporter 2 Inhibitors With Time to Dementia: A Population-Based Cohort Study

OBJECTIVE

Type 2 diabetes (T2D) increases dementia risk, but clear evidence to recommend interventions that can mitigate that risk remains lacking. This population-based retrospective cohort study aimed to determine whether new use of sodium-glucose cotransporter 2 (SGLT2) inhibitors compared with dipeptidyl peptidase 4 (DPP-4) inhibitors was associated with lower dementia risk.

RESEARCH DESIGN AND METHODS

Ontario residents aged ≥66 years who were new users of an SGLT2 inhibitor or a DPP-4 inhibitor from 1 July 2016 to 31 March 2021 entered the cohort. Incident dementia was identified using a validated algorithm for Alzheimer's disease and related dementias. Propensity score-weighted Cox proportional hazards models were used to obtain adjusted hazard ratios (aHR) and CIs for time to incident dementia. To address reverse causality and disease latency, the observation window started at 1-year lag time from cohort entry. The primary analysis followed intention-to-treat exposure definition, and a secondary as-treated analysis was performed.

RESULTS

Among 106,903 individuals, SGLT2 inhibitors compared with DPP-4 inhibitors were associated with lower risk of dementia (14.2/1,000 person-years; aHR 0.80 [95% CI 0.71-0.89]) over a mean follow-up of 2.80 years from cohort entry. When stratified by different SGLT2 inhibitors, dapagliflozin exhibited the lowest risk (aHR 0.67 [95% CI 0.53-0.84]), followed by empagliflozin (aHR 0.78 [95% CI 0.69-0.89]), whereas canagliflozin showed no association (aHR 0.96 [95% CI 0.80-1.16]). The as-treated analysis observed a larger association (aHR 0.66 [95% CI 0.57-0.76]) than the intention-to-treat analysis.

CONCLUSIONS

SGLT2 inhibitors showed an association with lower dementia risk in older people with T2D. Randomized controlled trials are warranted.

All-cause and cardiorenal mortality in 6 million adults with and without type 2 diabetes: A comparative, trend analysis in Canada, Spain, and the UK

AIMS

To understand geographical and temporal patterns in the diabetes gap, the excess mortality risk associated with type 2 diabetes (T2D), in three high-income countries.

METHODS

Using databases from Canada (Ontario), Spain (Catalonia) and the UK (England), we harmonized the study design and the analytical strategy to extract information on subjects aged over 35 years with incident T2D between 1998 and 2018 matched to up to five subjects without diabetes. We used Poisson models to estimate age-specific mortality trends by diabetes status and rate ratios and rate differences associated with T2D.

RESULTS

In more than 6 million people, 694 454 deaths occurred during a follow-up of 52 million person-years. Trends in all-cause mortality rates differed between Ontario and England; yet, the diabetes gaps were very similar in recent years: in 2018, we estimated 1.3 (95% confidence interval: 0.8, 1.8) and 0.8 (0.2, 1.5) more deaths per 1000 person-years in 50-year-old men with diabetes in Ontario and England, respectively, and 8.9 (6.1, 11.7) and 12.1 (9.1, 15.1) in 80-year-old men; between-country differences were small also in women. In Catalonia, rate ratios comparing T2D with no diabetes in men in 2018 were 1.53 (1.11, 2.11) at 50 years old, 0.88 (0.72, 1.06) at 60 years old, 0.74 (0.60, 0.90) at 70 years old and 0.81 (0.66, 1.00) at 80 years old, indicating lower mortality rates in men with T2D from the age of 60 years; rates were similar in women with and without diabetes at all ages. The diabetes gaps in cardiorenal mortality mirrored those of all-cause mortality: we observed consistent reductions in the proportions of cardiorenal deaths in subjects aged 80 years but variations in subjects aged ≤70 years, regardless of the presence of diabetes.

CONCLUSIONS

By reducing the confounding impact of epidemiological and analytical differences, this study showed geographical similarities and differences in the diabetes gap: an excess risk of all-cause and cardiorenal mortality in subjects with T2D is still present in Ontario and England in recent years, particularly in elderly subjects. Conversely, there were very small gaps in young men with T2D or even lower mortality rates in older subjects with T2D in Catalonia.

An Evaluation of Virtual Care for Gestational Diabetes Using the Quadruple Aim Framework: Assessment of Patient and Provider Experience, Cost and Clinical Outcomes

OBJECTIVE

Our aim in this study was to evaluate the impact of virtual care for gestational diabetes mellitus (GDM) in the context of the COVID-19 pandemic.

METHODS

This multiple methods program evaluation used the Quadruple Aim Framework. The impact on patient experience, cost and provider satisfaction was assessed using surveys and interviews. Chi-square and Poisson statistics were used to compare clinical outcomes before (April 2019 to February 2020) and after (May 2020 to March 2021) the shift to virtual care.

RESULTS

Patient experience surveys were completed by 85 women. Most of them rated their virtual care experience as good or excellent (93%), with a preference for continued virtual visits in the future (84%). Most respondents felt virtual care saved them money (93%) and time (98%). Six health-care providers at the Diabetes in Pregnancy Clinic were interviewed and all believed the switch to virtual care was largely positive. Overall, interview transcripts revealed that health-care providers were happy with the transition, although nurses initially perceived an increased workload. There were no significant differences in rates of cesarean section procedures, macrosomia, neonatal intensive care unit admissions or the proportion of appointments at which insulin was initiated between in-person and virtual care patient outcomes. There was a decreased proportion of missed appointments after the switch to virtual care (6.15% vs 1.21%, p<0.0001).

CONCLUSIONS

There has been high patient and provider satisfaction with virtual GDM care, with no difference in clinical outcomes and fewer missed appointments. Virtual GDM care should remain an option in the future.

Trends in the Association Between Diabetes and Cardiovascular Events, 1994-2019

This study uses administrative health care data from Ontario, Canada, to assess whether changes in diabetes management practices have affected trends in the association between diabetes vs prior cardiovascular disease and risk of cardiovascular events from 1994 to 2019 among adults aged 20 to 84 years.

Mediating effect of vascular risk factors underlying the link between gestational diabetes and cardiovascular disease

BACKGROUND

Women with gestational diabetes (GDM) have an elevated lifetime incidence of cardiovascular disease (CVD), but the basis of this excess risk remains to be established. In this context, we hypothesized that chronic exposure to adverse cardiovascular risk factors may contribute to their elevated risk of CVD. We thus sought to quantify the determinants of CVD risk in women with a history of GDM by performing mediation analyses.

METHODS

Women in Ontario, Canada, with a live-birth pregnancy between Jan 1998 and Dec 2017 (n=757,541) were followed for a median of 13.2 years and stratified into the following 4 groups: women with GDM who developed CVD (GDM+/CVD+); women without GDM who developed CVD (GDM-/CVD+); those with GDM but no CVD (GDM+/CVD-); and those with neither GDM nor CVD (GDM-/CVD-). Lipids (total cholesterol, LDL, HDL, triglycerides) and glycemic variables (A1c, fasting glucose) were measured between 4.3±3.0 and 4.8±3.4 times over follow-up.

RESULTS

On successive measurements at a median of 4.8, 7.1, and 8.7 years postpartum, respectively, each lipid and glycemic measure progressively worsened from GDM-/CVD- to GDM+/CVD- to GDM-/CVD+ to GDM+/CVD+ (all p&lt;0.0001). At each point in time, each of the lipid and glycemic measures was significantly worse in GDM+/CVD+ compared to GDM+/CVD- (all p&lt;0.001). Moreover, among women who did not develop CVD, all lipid and glycemic measures were significantly worse in those with previous GDM (all p&lt;0.001 for GDM+/CVD- vs GDM-/CVD-). Mediation analyses revealed that the dominant determinants of CVD risk in women with GDM were A1c (56.0% mediation, 95%CI 47.4-67.8) and fasting glucose (47.4%, 38.8-60.8), followed by HDL (25.2%, 21.3-30.7) and triglycerides (12.1%, 9.7-15.6). Upon exclusion of those who developed diabetes during follow-up, the key determinants were HDL (40.8%), fasting glucose (37.7%), A1c (28.6%), triglycerides (21.0%), and LDL (9.9%).

CONCLUSIONS

Adverse glycemic and lipid measures mediate the elevated risk of CVD in women with previous GDM, with the impact of lipids particularly evident in those who do not develop diabetes. These findings thus identify potential targets for risk factor monitoring and ultimately early intervention towards the goal of primary prevention of CVD in this at-risk patient population.

Association of Concomitant Gestational Hypertensive Disorders and Gestational Diabetes With Cardiovascular Disease

IMPORTANCE

Accruing evidence suggests that gestational hypertensive disorders (GHTD) and gestational diabetes (GD) are each associated with an increased risk of cardiovascular disease (CVD). However, the extent to which the co-occurrence of GHTD and GD is associated with the risk of CVD remains largely unknown.

OBJECTIVE

To estimate the individual and joint associations of GHTD and GD with incident CVD.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used the Ministry of Health and Long-Term Care of Ontario (Canada) health care administrative databases. All women in Ontario with a GHTD and/or GD diagnosis, and a live-birth singleton delivery between July 1, 2007, and March 31, 2018, were considered for inclusion. Women with pregravid diabetes, hypertension, or cardiovascular disease were excluded. Statistical analysis was performed from November 2021 to September 2022.

EXPOSURES

GD and/or GHTD, defined using diagnosis coding.

MAIN OUTCOMES AND MEASURES

Individual and joint associations of GHTD and GD with incident CVD (including a composite of myocardial infarction, acute coronary syndrome, stroke, coronary artery bypass grafting, percutaneous coronary intervention, or carotid endarterectomy), estimated using Cox regression models, adjusting for relevant cardiometabolic risk factors. The follow-up extended from the index pregnancy until March 31, 2020.

RESULTS

Among 886 295 eligible women (mean [SD] age, 30 [5.6] years; 43 861 [4.9%] with isolated GHTD, 54 061 [6.1%] with isolated GD, and 4975 [0.6%] with GHTD and GD), there were 1999 CVD events over 12 years of follow-up. In the early postpartum phase (first 5 years post partum), there was no association of co-occurrence of GTHD and GD (adjusted hazard ratio [aHR], 1.42, 95% CI, 0.78-2.58) or GD alone (aHR, 0.80; 95% CI, 0.60-1.06) with CVD; there was an association between isolated GTHD and incident CVD compared with no GTHD and no GD (aHR, 1.90; 95% CI, 1.51-2.35). In the late postpartum period (after the initial 5 years post partum), compared with no GD and no GHTD, isolated GHTD (aHR, 1.41, 95% CI, 1.12-1.76) and co-occurrence of GHTD and GD (aHR, 2.43, 95% CI, 1.60-3.67) were each associated with a higher risk of incident CVD. There was no association between isolated GD and incident CVD.

CONCLUSIONS AND RELEVANCE

In this cohort study, GHTD was associated with a high risk of CVD post partum, and the co-occurrence of GD and GHTD was associated with a much greater postpartum CVD risk. These findings suggest that CVD preventive care is particularly needed in the aftermath of combined GD and GHTD.

Characteristics of new users of recent antidiabetic drugs in Canada and the United Kingdom

BACKGROUND

Characteristics of patients using newer 2^nd and 3^rd line antidiabetic drugs in a real-world setting are poorly understood. We described the characteristics of new users of sodium-glucose co-transporter-2 inhibitors (SGLT-2i), dipeptidyl peptidase-4 inhibitors (DPP-4i), and glucagon-like peptide-1 receptor agonists (GLP-1 RA) in Canada and the United Kingdom (UK) between 2016 and 2018.

METHODS

We conducted a multi-database cohort study using administrative health databases from 7 Canadian provinces and the UK Clinical Practice Research Datalink. We assembled a base cohort of antidiabetic drug users between 2006 and 2018, from which we constructed 3 cohorts of new users of SGLT-2i, DPP-4i, and GLP-1 RA between 2016 and 2018.

RESULTS

Our cohorts included 194,070 new users of DPP-4i, 166,722 new users of SGLT-2i, and 27,719 new users of GLP-1 RA. New users of GLP-1 RA were more likely to be younger (mean ± SD: 56.7 ± 12.2 years) than new users of DPP-4i (67.8 ± 12.3 years) or SGLT-2i (64.4 ± 11.1 years). In Canada, new users of DPP-4i were more likely to have a history of coronary artery disease (22%) than new users of SGLT-2i (20%) or GLP-1 RA (15%).

CONCLUSION

Although SGLT-2i, DPP-4i, and GLP-1 RAs are recommended as 2^nd or 3^rd line therapy for type 2 diabetes, important differences exist in the characteristics of users of these drugs. Contrary to existing guidelines, new users of DPP-4i had a higher prevalence of cardiovascular disease at baseline than new users of SGLT2i or GLP-1RA.

Screening Accuracy of the 50 g-Glucose Challenge Test in Twin Compared With Singleton Pregnancies

CONTEXT

The optimal 50 g-glucose challenge test (GCT) cutoff for the diagnosis of gestational diabetes mellitus (GDM) in twin pregnancies is unknown.

OBJECTIVE

This work aimed to explore the screening accuracy of the 50 g-GCT and its correlation with the risk of large for gestational age (LGA) newborn in twin compared to singleton pregnancies. A population-based retrospective cohort study (2007-2017) was conducted in Ontario, Canada. Participants included patients with a singleton (n = 546 892 [98.4%]) or twin (n = 8832 [1.6%]) birth who underwent screening for GDM using the 50 g-GCT.

METHODS

We compared the screening accuracy, risk of GDM, and risk of LGA between twin and singleton pregnancies using various 50 g-GCT cutoffs.

RESULTS

For any given 50 g-GCT result, the probability of GDM was higher (P = .0.007), whereas the probability of LGA was considerably lower in the twin compared with the singleton group, even when a twin-specific growth chart was used to diagnose LGA in the twin group (P < .001). The estimated false-positive rate (FPR) for GDM was higher in twin compared with singleton pregnancies irrespective of the 50 g-GCT cutoff used. The cutoff of 8.2 mmol/L (148 mg/dL) in twin pregnancies was associated with an estimated FPR (10.7%-11.1%) that was similar to the FPR associated with the cutoff of 7.8 mmol/L (140 mg/dL) in singleton pregnancies (10.8%).

CONCLUSION

The screening performance of the 50 g-GCT for GDM and its correlation with LGA differ between twin and singleton pregnancies.

The prognostic value of the oral glucose tolerance test for future type-2 diabetes in nulliparous pregnant women testing negative for gestational diabetes

AIM

To determine the prognostic value of the antepartum 75g-oral glucose tolerance test (OGTT) for future type 2 diabetes mellitus (T2DM) in nulliparous pregnant women who tested negative for GDM.

METHODS

A population-based retrospective cohort study of nulliparous pregnant women who underwent testing for GDM using a 75g-OGTT in Ontario, Canada (2007-2017). The overwhelming majority of women in Ontario undergo screening using the preferred 2-step approach where the 75g-OGTT is performed following an abnormal non-fasting 1 h 50g-glucose challenge test. The relationship between the 75g-OGTT results in women who tested negative for GDM (defined as normal glucose at fasting, 1 and 2 h post 75g-glucose load) and future T2DM (as recorded in the Ontario Diabetes Database by the end date of follow up period) was explored.

FINDINGS

Of the 162,622 women who underwent 75g-OGTT during the study period, there were 41,507 (75.0%) who met the study criteria. In women without GDM, the adjusted hazard ratios (aHR) for T2DM were-At fasting 2.82 (95%-CI 2.18-3.64), at 1 h 1.26 (1.15-1.37), at 2 h 1.14 (1.04-1.25) for a 1 mmol/L increase in glucose. A model that combined all 3 OGTT values and clinical characteristics could detect 43% (42.6%-43.4%) of those who developed T2DM at 5-years post the index pregnancy for a false-positive rate of 20%.

INTERPRETATION

The results of the antepartum OGTT can be used to refine the future risk of T2DM even in nulliparous pregnant women who tested negative for GDM.

Five comparative cohorts to assess the risk of genital tract infections associated with sodium-glucose cotransporter-2 inhibitors initiation in type 2 diabetes mellitus

AIM

To assess the association between SGLT-2 inhibitors initiation and genital tract infections (GTIs) among patients with type 2 diabetes.

METHODS

A population-based cohort study using administrative healthcare data from Alberta, Canada, and primary care data from the UK's Clinical Practice Research Datalink (CPRD). Among new metformin users, we identified new users of SGLT-2 inhibitors and five active comparator cohorts (new users of dipeptidyl peptidase-4 (DPP-4) inhibitors, sulfonylureas (SU), glucagon-like peptide-1 receptor agonists (GLP-1 RA), thiazolidinediones (TZD) and insulin). The outcome of interest was a composite GTI outcome. In each cohort, we used high-dimensional propensity score matching to adjust for confounding and conditional Cox proportional hazards regression to estimate the hazard ratios (HR). We used random-effects meta-analysis to combine aggregate data across databases.

RESULTS

The risk of GTI was higher for SGLT-2 inhibitors users compared with DPP4inhibitor users (pooled HR 2.68, 95% CI 2.19 3.28), SU users (3.29, 2.62-4.13), GLP1-RA users (2.51, 1.90-3.31), TZD users (4.17, 2.46-7.08) and insulin users (1.86, 1.27-2.73).

CONCLUSION

In five comparative cohorts, SGLT-2 inhibitors initiation is associated with a higher risk of GTIs. These findings from real-world data are consistent with placebo-controlled randomized controlled trials.

Trends in glucose testing among individuals without diabetes in Ontario between 2010 and 2017: a population-based cohort study

BACKGROUND

Early identification of people with diabetes or prediabetes enables greater opportunities for glycemic control and management strategies to prevent related complications. To identify gaps in screening for these conditions, we examined population trends in receipt of timely glucose testing overall and in specific clinical subgroups.

METHODS

Using linked administrative databases, we conducted a retrospective cohort study of people aged 40 years and older without diabetes at baseline. Our primary outcome was up-to-date glucose testing, defined as having received testing at least once in the 3 years before each index year from 2010 to 2017, using linked administrative databases of people residing in Ontario, Canada. We calculated rates of up-to-date testing by age group, sex, ethnicity (South Asian, Chinese, general population) and comorbidities (hypertension, hyperlipidemia, cardiovascular disease).

RESULTS

Over the 8-year study period, up-to-date glucose testing rates were stable at 67% for men and 77% for women (both relative risk 1.00 per year; 95% confidence interval 1.00-1.00). Testing rates were significantly lower in men than in women (all age groups p < 0.001) and lower in younger than older age groups (except those aged ≥ 80 yr). South Asian people had the highest testing rates, although among people aged 70 years or older, testing was highest in the general population (p < 0.001). Among people with hypertension, hyperlipidemia and cardiovascular disease, annual testing rates were also stable, but only 58% overall among people with hypertension.

INTERPRETATION

We found lower glucose testing rates in younger men and people with hypertension. Our findings reinforce the need for initiatives to increase awareness of glycemic testing.

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.

Prediction models of diabetes complications: a scoping review

BACKGROUND

Diabetes often places a large burden on people with diabetes (hereafter 'patients') and the society, that is, in part attributable to its complications. However, evidence from models predicting diabetes complications in patients remains unclear. With the collaboration of patient partners, we aimed to describe existing prediction models of physical and mental health complications of diabetes.

METHODS

Building on existing frameworks, we systematically searched for studies in Ovid-Medline and Embase. We included studies describing prognostic prediction models that used data from patients with pre-diabetes or any type of diabetes, published between 2000 and 2020. Independent reviewers screened articles, extracted data and narratively synthesised findings using established reporting standards.

RESULTS

Overall, 78 studies reported 260 risk prediction models of cardiovascular complications (n=42 studies), mortality (n=16), kidney complications (n=14), eye complications (n=10), hypoglycaemia (n=8), nerve complications (n=3), cancer (n=2), fracture (n=2) and dementia (n=1). Prevalent complications deemed important by patients such as amputation and mental health were poorly or not at all represented. Studies primarily analysed data from older people with type 2 diabetes (n=54), with little focus on pre-diabetes (n=0), type 1 diabetes (n=8), younger (n=1) and racialised people (n=10). Per complication, predictors vary substantially between models. Studies with details of calibration and discrimination mostly exhibited good model performance.

CONCLUSION

This rigorous knowledge synthesis provides evidence of gaps in the landscape of diabetes complication prediction models. Future studies should address unmet needs for analyses of complications n> and among patient groups currently under-represented in the literature and should consistently report relevant statistics. SCOPING REVIEW REGISTRATION: https://osf.io/fjubt/.

Glucose-lowering drugs, cognition, and dementia: The clinical evidence

Type 2 diabetes mellitus (T2DM) is an important risk factor for dementia. The possibility to mitigate this risk by controlling T2DM is compelling; however, different glucose-lowering drugs have different effects on the brain by virtue of their different mechanisms of action. The clinical and epidemiological data appear mixed, warranting careful critical evaluation of the human studies. Here we examine the evidence in the context of dementia prevention and treatment, both for people with and without T2DM. We discuss the evidence on this scaffold of research directions, identifying methodological complexities in the extant literature (e.g. comparator discrepancies, changes in the therapeutic landscape), and the implications of different outcome measures (e.g. neuropsychological). We consider possible implications of cerebrovascular protection vs. effects on progression of neurodegenerative proteinopathy, and we present a research roadmap for glucose-lowering drugs in cognitive neurology, including neuroimaging, and fluid biomarkers. We conclude that there is great potential to advance personalized strategies to prevent and treat dementia with glucose-lowering drugs.