Cardiovascular Safety in Type 2 Diabetes With Sulfonylureas as Second-Line Drugs: A Nation-Wide Population-Based Comparative Safety Study

OBJECTIVE

To assess the real-world cardiovascular (CV) safety for sulfonylureas (SU), in comparison with dipeptidylpeptidase-4 inhibitors (DPP4i) and thiazolidinediones (TZD), through development of robust methodology for causal inference in a whole nation study.

RESEARCH DESIGN AND METHODS

A cohort study was performed including people with type 2 diabetes diagnosed in Scotland before 31 December 2017, who failed to reach HbA1c 48 mmol/mol despite metformin monotherapy and initiated second-line pharmacotherapy (SU/DPP4i/TZD) on or after 1 January 2010. The primary outcome was composite major adverse cardiovascular events (MACE), including hospitalization for myocardial infarction, ischemic stroke, heart failure, and CV death. Secondary outcomes were each individual end point and all-cause death. Multivariable Cox proportional hazards regression and an instrumental variable (IV) approach were used to control confounding in a similar way to the randomization process in a randomized control trial.

RESULTS

Comparing SU to non-SU (DPP4i/TZD), the hazard ratio (HR) for MACE was 1.00 (95% CI: 0.91-1.09) from the multivariable Cox regression and 1.02 (0.91-1.13) and 1.03 (0.91-1.16) using two different IVs. For all-cause death, the HR from Cox regression and the two IV analyses was 1.03 (0.94-1.13), 1.04 (0.93-1.17), and 1.03 (0.90-1.17).

CONCLUSIONS

Our findings contribute to the understanding that second-line SU for glucose lowering are unlikely to increase CV risk or all-cause mortality. Given their potent efficacy, microvascular benefits, cost effectiveness, and widespread use, this study supports that SU should remain a part of the global diabetes treatment portfolio.

Manganese enhanced magnetic resonance imaging in type 1 and type 2 diabetes mellitus

Background

The pathophysiology of diabetic cardiomyopathy has yet to be established although pre-clinical studies suggest a role for altered myocardial calcium handling. Manganese-enhanced magnetic resonance imaging (MEMRI) is a novel non-invasive method of assessing in vivo myocardial calcium handling.

Purpose

To investigate whether myocardial calcium handling is impaired in patients with either type 1 or type 2 diabetes mellitus in the absence of underlying heart disease.

Methods

In a prospective case-control study, patients with type 1 (n=19) or type 2 (n=10) diabetes mellitus and healthy volunteers (n=15) underwent MEMRI. Participants with prior coronary artery disease, cardiomyopathy or an abnormal electrocardiogram were excluded. Manganese dipyridoxyl diphosphate (0.1 mL/kg) was administered over 10 min and myocardial T1 mapping was performed prior to and every 2.5 min for 30 min after contrast infusion (Figure 1). Quantitative manganese uptake analysis was performed by measuring T1 relaxation times in a region of interest within the interventricular septum and compared to the left ventricular blood pool. The rate of myocardial manganese uptake was determined by Patlak modelling [1].

Results

Participants with type 1 and type 2 diabetes mellitus were older (50±13 and 55±15.3 years) than the healthy volunteers (32±10 years). All participants had preserved left ventricular ejection fraction (type 1 diabetes mellitus, 67.7±6.1%; type 2 diabetes mellitus, 66.8±3.2%; healthy volunteers, 65±3.5%). Mean myocardial manganese uptake was reduced in participants with both type 1 (6.4±0.6 mL/100 g of tissue/min) and type 2 (6.4±0.5 mL/100 g of tissue/min) diabetes mellitus compared with healthy volunteers (8.3±0.5 mL/100 g of tissue/min; p<0.0001 for both, Figure 2). There were no differences in myocardial manganese uptake between those with type 1 or type 2 diabetes mellitus (p=0.22). There was no statistically significant correlation between myocardial manganese uptake and age in the study population (r=−0.28, p=0.07).

Conclusion

Using MEMRI, we have demonstrated that myocardial calcium handling is impaired in patients with either type 1 or type 2 diabetes mellitus even in the absence of left ventricular systolic dysfunction. This suggests altered myocardial calcium handling may underlie, or contribute to, diabetic cardiomyopathy which has implications developing novel therapeutic targets for the prevention and treatment of diabetic cardiomyopathy.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): British Heart Foundation - Clinical Research Training Fellowship (FS/CRTF/20/24087)AstraZeneca - Investigator initiated award (ESR-19-20118)

European Expert Consensus on Practical Management of Specific Aspects of Parathyroid Disorders in Adults and in Pregnancy: Recommendations of the ESE Educational Program of Parathyroid Disorders

This European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders (PARAT) in 2019, were discussed during two virtual workshops in 2021, and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosing to familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represent areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT, need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborns children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed for a broader clinical audience, and were developed with focus on endocrinologists in training.

Foot Ulcer and Risk of Lower Limb Amputation or Death in People With Diabetes: A National Population-Based Retrospective Cohort Study

OBJECTIVE

To describe incidence of foot ulceration and amputation-free survival associated with foot ulceration status in a national population-based cohort study of people with diabetes.

RESEARCH DESIGN AND METHODS

The study population included 233,459 people with diabetes who were alive in Scotland on 1 January 2012 identified from the national population-based register (national prevalence 4.9%). Characteristics of patients identified from linked hospital and mortality records during follow-up to the end of November 2017 were compared by outcome. Cox regression was used to assess the association between history of foot ulcer and amputation-free survival.

RESULTS

The population included 23,395 people with type 1 diabetes and 210,064 people with type 2 diabetes. In total there were 13,093 (5.6%) people who had a previous foot ulceration, 9,023 people who developed a first ulcer, 48,995 who died, and 2,866 who underwent minor or major amputation during follow-up. Overall incidence of first-time foot ulcers was 7.8 per 1,000 person-years (95% CI7.6-7.9) and 11.2 (11.0-11.4) for any ulcer. Risk factors for reduced amputation-free survival included social deprivation, mental illness, and being underweight in addition to conventional cardiovascular risk factors. Adjusted hazard ratios (95% CI) were 2.09 (1.89-2.31) for type 1 diabetes and 1.65 (1.60-1.70) for type 2 diabetes.

CONCLUSIONS

The overall incidence of foot ulceration in a population-based study of people with diabetes was 11.2 per 1,000 person-years. Foot ulceration is associated with lower amputation-free survival rate, a potential measure of effectiveness of care among people with diabetes. Mental illness and social deprivation are also highlighted as risk factors.

Derivatization with 2-hydrazino-1-methylpyridine enhances sensitivity of analysis of 5α-dihydrotestosterone in human plasma by liquid chromatography tandem mass spectrometry

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Quantitative analysis of low abundance androgens in human plasma.

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Quantitation of androgens over physiological range in men and post-menopausal women.

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Use of hydrazine derivatives improves analytical sensitivity.

Liquid Chromatography tandem mass spectrometry (LC-MS/MS) is the gold-standard approach for androgen analysis in biological fluids, superseding immunoassays in selectivity, particularly at low concentrations. While LC-MS/MS is established for analysis of testosterone and androstenedione, 5α-dihydrotestosterone (DHT) presents greater analytical challenges. DHT circulates at low nanomolar concentrations in men and lower in women, ionizing inefficiently and suffering from isobaric interference from other androgens. Even using current LC-MS/MS technology, large plasma volumes (>0.5 mL) are required for detection, undesirable clinically and unsuitable for animals. This study investigated derivatization approaches using hydrazine-based reagents to enhance ionization efficiency and sensitivity of analysis of DHT by LC-MS/MS. Derivatization of DHT using 2-hydrazino-1-methylpyridine (HMP) and 2-hydrazino-4-(trifluoromethyl)-pyrimidine (HTP) were compared. A method was validated using an UHPLC interfaced by electrospray with a triple quadruple mass spectrometer , analyzing human plasma (male and post-menopausal women) following solid-phase extraction. HMP derivatives were selected for validation affording greater sensitivity than those formed with HTP. HMP derivatives were detected by selected reaction monitoring (DHT-HMP m/z 396→108; testosterone-HMP m/z 394→108; androstenedione-HMP m/z 392→108). Chromatographic separation of androgen derivatives was optimized, carefully separating isobaric interferents and acceptable outputs for precision and trueness achieved following injection of 0.4 pg on column (approximately 34 pmol/L). HMP derivatives of all androgens tested could be detected in low plasma volumes: male (100 µL) and post-menopausal female (200 µL), and derivatives were stable over 30 days at -20°C. In conclusion, HMP derivatization, in conjunction with LC-MS/MS, is suitable for quantitative analysis of DHT, testosterone and androstenedione in low plasma volumes, offering advantages in sensitivity over current methodologies.

MON-118 Biochemical and Clinical Correlates of Subcutaneous Adipose mRNA Transcript Levels in Men with T2DM

Background: Altered profiles of subcutaneous adipose tissue gene expression have been independently associated with insulin sensitivity. T2DM has been associated with higher levels of adipokines, inflammatory cytokines and lower plasma sex steroid concentrations. We sought to examine the interplay between these factors, specifically with respect to their associations with mRNA transcript levels in subcutaneous adipose tissue. Methods: Cross-sectional assessment of 162 men with T2DM not treated with insulin (Median age 57 [51 - 61]). Basic anthropometric parameters (including body fat by bioimpedance) were measured. Testosterone, DHT, A4, 17-OHP, E2 and E1 measured by LCMS; TNFα, IL-6, IL-8, IL-1ß, MCP-1, leptin, FSH, LH, SHBG and insulin by ELISA (all fasting) and RT-PCR assessed a panel of 23 gene transcripts in adipose tissue (n = 115). Results: Testosterone (R -.273) & DHT (R -.352) were associated with HOMA-IR independent of BMI but not after adjustment for SHBG. No other biochemical parameters were independently associated with HOMA-IR. Waist circumference (R .351) and HbA1c (R .284) but not IL-6 (R .315) were independently associated with CYP19 expression. HbA1c (R -.222) and A4 (R .207) were independently associated with estrogen receptor α expression. FSH (R -.229) was independently associated with androgen receptor expression. Insulin (R .274) and IL-6 (R .245) were independently associated with adipose leptin expression. Associations with BMI (R .275), DHT (R -.208) and FSH (R -.211) were not significant after adjustment for confounders. Insulin receptor expression was only independently associated with fat mass (R -.378). PPARγ expression was only significantly correlated with HbA1c (R -.204) whilst, after adjustment, MCP-1 expression was only independently associated with percentage fat (R .332). Retinol binding protein 4 expression was independently associated with HbA1c (-.323), MCP-1 (R .297) and FSH (-.254). Conclusion: Circulating sex steroids were not associated with insulin resistance or differences across a wide range of adipose mRNA transcript levels in men with T2DM. Insulin or HbA1c appeared to be a stronger correlate for adipose transcript profiles than circulating adipokines or cytokines. Recent evidence suggests FSH may exert direct effects upon adipose tissue and these findings potentially support this hypothesis.

MON-170 Low Plasma Glucose Results from Primary Care Are Not Associated with Morbidity, Mortality, or Underlying Hypoglycemic Disorders

Background: Low glucose is a relatively common primary care referral to specialist endocrine services. However the prevalence of endocrine disease causing endogenous hypoglycemia is extremely rare. We sought to determine whether low plasma glucose in primary care was associated with adverse clinical outcomes or underlying hypoglycemic disorders. Methods: We obtained all plasma glucose results <72mg/dl originating from primary care within our catchment population (n = 800,00), in non-diabetic individuals (20,145 people [77.6% female]) aged 18 - 40 years, between 2002 and 2017. These data were linked to national admission, mortality, cancer and diabetes registers to assess associations with mortality and morbidity. Results: Median follow-up was 4.8 years (IQR 2.6 - 7.8). Median age was 29 years (24 - 34). Glucose was marginally higher in women 65 mg/dl vs. 63 mg/dl, P < 0.0001. Only 0.3% of patients were assessed in an endocrine clinic for evaluation of hypoglycaemia. Glucose concentration was < 40 mg/dl in 0.63% (category A), 40 - <54 mg/dl in 8.7% (category B), 54 - <63 mg/dl in 28.0% (category C) and ≥63 mg/dl in 62.6% (category D). A history of eating disorder was present in 2.4% (A), 1.1% (B), 0.4% (C) and 0.3% (D), P < 0.0001. Likelihood of admission to hospital with hypoglycaemia (P < 0.001) and electrolyte disturbance (P < 0.001) was also greater in those in the lower glucose categories. Increasing age (HR 1.03, P < 0.001) and male gender (HR 4.20, P < 0.001), but not glucose < 54 mg/dl (HR 0.89, P = 0.79), were associated with mortality (n = 72). The risk of a subsequent new diagnosis of cancer or hospital admission with incident cardiovascular, renal or liver disease was not related to glucose category. Hospital admission with infectious disease was more likely (3.3%) in those with glucose ≥ 54mg/dl compared to those with lower glucose (2.2%), P = 0.01. Incident diabetes was observed in 0.2% of those with glucose < 54 mg/dl and in 0.6% of those with glucose ≥ 54mg/dl (OR 3.0, P = 0.009). No cases of insulinoma were detected based on the results of these tests. Conclusion: Low plasma glucose results from primary care are almost never indicative of an endogenous hyperinsulinemic disorder and are not associated with adverse outcomes in adults up to 40 years of age. Underlying eating disorder should be considered in this context. Assessment by an endocrinologist should be limited to cases where Whipple’s triad is present.