Search

Introduction: For a long time, metformin has been the first-line treatment for glycemic control in type 2 diabetes; however, the results of recent cardiovascular outcome trials of sodium-glucose co-transporter 2 inhibitors and glucagon-like peptide 1 receptor agonists have caused many to question metformin's position in the guidelines. Although there are several plausible mechanisms by which metformin might have beneficial cardiovascular effects, for example, its anti-inflammatory effects and metabolic properties, and numerous observational data suggesting improved cardiovascular outcomes with metformin use, the main randomized clinical trial data for metformin was published over 20 years ago. Nevertheless, the overwhelming majority of participants in contemporary type 2 diabetes trials were prescribed metformin., Areas Covered: In this review, we will summarize the potential mechanisms of cardiovascular benefit with metformin, before discussing clinical data in individuals with or without diabetes., Expert Opinion: Metformin may have some cardiovascular benefit in patients with and without diabetes, however the majority of clinical trials were small and are before the use SGLT2 inhibitors and GLP1-RAs. Larger contemporary randomized trials, with metformin evaluating its cardiovascular benefit are warranted.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have consistently demonstrated improved outcomes in patients with heart failure with or without type 2 diabetes; however, the mechanisms contributing to these benefits remain poorly understood. Although SGLT2 inhibitors do have glucose-lowering effects, it is unlikely that their cardiovascular benefits are solely due to improved glycemic control. This improved glycemia leads to consequent metabolic effects that could provide further explanation for their action. This review discusses the glucose-lowering and metabolic effects of SGLT2 inhibitors and how these might lead to improved cardiovascular outcomes in patients with heart failure., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Improved identification of individuals with type 2 diabetes at high cardiovascular (CV) risk could help in selection of newer CV risk-reducing therapies. The aim of this study was to determine whether retinal vascular parameters, derived from retinal screening photographs, alone and in combination with a genome-wide polygenic risk score for coronary heart disease (CHD PRS) would have independent prognostic value over traditional CV risk assessment in patients without prior CV disease., Research Design and Methods: Patients in the Genetics of Diabetes Audit and Research Tayside Scotland (GoDARTS) study were linked to retinal photographs, prescriptions, and outcomes. Retinal photographs were analyzed using VAMPIRE (Vascular Assessment and Measurement Platform for Images of the Retina) software, a semiautomated artificial intelligence platform, to compute arterial and venous fractal dimension, tortuosity, and diameter. CHD PRS was derived from previously published data. Multivariable Cox regression was used to evaluate the association between retinal vascular parameters and major adverse CV events (MACE) at 10 years compared with the pooled cohort equations (PCE) risk score., Results: Among 5,152 individuals included in the study, a MACE occurred in 1,017 individuals. Reduced arterial fractal dimension and diameter and increased venous tortuosity each independently predicted MACE. A risk score combining these parameters significantly predicted MACE after adjustment for age, sex, PCE, and the CHD PRS (hazard ratio 1.11 per SD increase, 95% CI 1.04-1.18, P = 0.002) with similar accuracy to PCE (area under the curve [AUC] 0.663 vs. 0.658, P = 0.33). A model incorporating retinal parameters and PRS improved MACE prediction compared with PCE (AUC 0.686 vs. 0.658, P < 0.001)., Conclusions: Retinal parameters alone and in combination with genome-wide CHD PRS have independent and incremental prognostic value compared with traditional CV risk assessment in type 2 diabetes., (© 2022 by the American Diabetes Association.)

Background: There are conflicting reports regarding the association of the macrolide antibiotic clarithromycin with cardiovascular (CV) events. A possible explanation may be that this risk is partly mediated through drug-drug interactions and only evident in at-risk populations. To the best of our knowledge, no studies have examined whether this association might be mediated via P-glycoprotein (P-gp), a major pathway for clarithromycin metabolism. The aim of this study was to examine CV risk following prescription of clarithromycin versus amoxicillin and in particular, the association with P-gp, a major pathway for clarithromycin metabolism., Methods and Findings: We conducted an observational cohort study of patients prescribed clarithromycin or amoxicillin in the community in Tayside, Scotland (population approximately 400,000) between 1 January 2004 and 31 December 2014 and a genomic observational cohort study evaluating genotyped patients from the Genetics of Diabetes Audit and Research Tayside Scotland (GoDARTS) study, a longitudinal cohort study of 18,306 individuals with and without type 2 diabetes recruited between 1 December 1988 and 31 December 2015. Two single-nucleotide polymorphisms associated with P-gp activity were evaluated (rs1045642 and rs1128503 -AA genotype associated with lowest P-gp activity). The primary outcome for both analyses was CV hospitalization following prescription of clarithromycin versus amoxicillin at 0-14 days, 15-30 days, and 30 days to 1 year. In the observational cohort study, we calculated hazard ratios (HRs) adjusted for likelihood of receiving clarithromycin using inverse proportion of treatment weighting as a covariate, whereas in the pharmacogenomic study, HRs were adjusted for age, sex, history of myocardial infarction, and history of chronic obstructive pulmonary disease. The observational cohort study included 48,026 individuals with 205,227 discrete antibiotic prescribing episodes (34,074 clarithromycin, mean age 73 years, 42% male; 171,153 amoxicillin, mean age 74 years, 45% male). Clarithromycin use was significantly associated with increased risk of CV hospitalization compared with amoxicillin at both 0-14 days (HR 1.31; 95% CI 1.17-1.46, p < 0.001) and 30 days to 1 year (HR 1.13; 95% CI 1.06-1.19, p < 0.001), with the association at 0-14 days modified by use of P-gp inhibitors or substrates (interaction p-value: 0.029). In the pharmacogenomic study (13,544 individuals with 44,618 discrete prescribing episodes [37,497 amoxicillin, mean age 63 years, 56% male; 7,121 clarithromycin, mean age 66 years, 47% male]), when prescribed clarithromycin, individuals with genetically determined lower P-gp activity had a significantly increased risk of CV hospitalization at 30 days to 1 year compared with heterozygotes or those homozygous for the non-P-gp-lowering allele (rs1045642 AA: HR 1.39, 95% CI 1.20-1.60, p < 0.001, GG/GA: HR 0.99, 95% CI 0.89-1.10, p = 0.85, interaction p-value < 0.001 and rs1128503 AA 1.41, 95% CI 1.18-1.70, p < 0.001, GG/GA: HR 1.04, 95% CI 0.95-1.14, p = 0.43, interaction p-value < 0.001). The main limitation of our study is its observational nature, meaning that we are unable to definitively determine causality., Conclusions: In this study, we observed that the increased risk of CV events with clarithromycin compared with amoxicillin was associated with an interaction with P-glycoprotein., Competing Interests: The authors have declared that no competing interests exist.

Metformin remains the first-line drug treatment for type 2 diabetes (T2D) in most guidelines not only because it achieves significant reduction in HbA1c but also because of a wealth of clinical experience regarding its safety and observational data that has shown that metformin use is associated with lower mortality rates when compared to sulphonylureas or insulin. Recently other diabetes drugs, particularly SGLT2 inhibitors (SGLT2i) and GLP1 receptor agonists (GLP1RA), have attracted considerable attention for their cardioprotective benefits reported in cardiovascular outcome trials (CVOTs). Randomised control trials on these newer drugs are on a larger scale but have shorter follow-up than UKPDS, the main study supporting metformin use. In a recent change to the European Society of Cardiology guidelines, metformin was replaced by SGLT2i and GLP1RA as first-line for T2D with atherosclerotic cardiovascular disease, whereas American Diabetes Association and UK-wide guidelines maintain metformin as first choice drug pharmacotherapy for all T2D. A definitive evidence-base for prioritisation of these drugs is currently missing because there are no head-to-head clinical trial data. Without such trials being forthcoming, innovative, pragmatic and low-cost 'real-world' trial approaches based on electronic health records may need to be harnessed to determine the correct priority, combinations of drugs and/or identify-specific patient populations most likely to benefit from each one., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: To evaluate the effects of proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors on major adverse cardiovascular events (MACE)., Methods: Our systematic review included randomised controlled trials if they studied PCSK9 inhibitors in patients for primary and/or secondary prevention of cardiovascular diseases or with hypercholesterolaemia/hyperlipidaemia. Dichotomous variables from individual studies were pooled by relative risks (RR) and their 95% CIs using the random-effect model. Risk difference (RD) in the 10-year frame was also estimated using the pooled RR and the estimated baseline risk using the control group. Grading of Recommendation Assessment, Development and Evaluation was used to assess the quality of evidence., Results: We included 54 trials with 97 910 patients in the analysis. Compared with controls, PCSK9 inhibitors significantly reduced the risk of MACE by 16% (RR, 0.84; 95% CI 0.79 to 0.89; RD: 47 fewer per 1000 vs 286 as the baseline risk; 95% CI 32 to 59 fewer), non-fatal myocardial infarction (MI) by 17% (RR, 0.83; 95% CI 0.74 to 0.93; RD, 35 fewer per 1000 vs 207 as the baseline; 95% CI 13 to 53 fewer) and any stroke by 25% (RR, 0.75; 95% CI 0.65 to 0.85; RD, 16 fewer per 1000 vs 61 as the baseline; 95% CI 9 to 21 fewer) with moderate quality evidence. No significant differences were found between PCSK9 inhibitors and control groups in all-cause mortality, cardiovascular death, heart failure or unstable angina with low-quality evidence., Conclusions: This study demonstrated that PCSK9 inhibitors could significantly reduce the risk of MACE, non-fatal MI and stroke., Trial Registration: PROSPERO; CRD42017073904., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

There are common clinical scenarios in chronic heart disease where no randomized controlled data exist to guide management, and it is likely that well-designed observational studies will have to be used to inform clinical practice. Showing the clinical applicability of this type of study design, using record linkage of population electronic health records, we have provided key observational evidence that use of renin–angiotensin-system (RAS) blockers is associated with better outcomes in patients with aortic stenosis and that metformin could be used safely as an antiglycemic drug in patients with diabetes and heart failure. Each of these pieces of underpinning research has made a major contribution to relevant international clinical practice guidelines, helped the Food and Drug Administration in their decision making and changed prescribing practice. [ABSTRACT FROM AUTHOR]