AIMS/HYPOTHESIS: Cardiovascular outcome trials (CVOTs) have demonstrated the benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i). However, serious adverse drug reactions have been reported. The risk/benefit ratio of SGLT2i remains unquantified. We aimed to provide an estimation of their risk/benefit ratio in individuals with type 2 diabetes.

METHODS

We conducted a systematic review (MEDLINE, up to 14 September 2021) and meta-analysis. We included randomised CVOTs assessing SGLT2i in individuals with type 2 diabetes with or without other diseases. We used the Cochrane 'Risk of bias' assessment tool. The primary outcomes were overall mortality, major adverse cardiovascular events (MACE), hospitalisation for heart failure (HHF), end-stage renal disease (ESRD), amputation, diabetic ketoacidosis (DKA) and reported genital infections. For each outcome, we estimated the incidence rate ratio (IRR) with a 95% CI; we then computed the number of events expected spontaneously and with SGLT2i.

RESULTS

A total of 46,969 participants from five double-blind, placebo-controlled international trials (weighted mean follow-up 3.5 years) were included. The prevalence of previous CVD ranged from 40.6% to 99.2%. The definition of reported genital infections ranged from 'genital mycotic infection' to 'genital infections that led to discontinuation of the trial regimen or were considered to be serious adverse events'. The number of included studies for each outcomes was five. The use of SGLT2i decreased the risk of all-cause death (IRR 0.86 [95% CI 0.78, 0.95]), MACE (IRR 0.91 [95% CI 0.86, 0.96]), HHF (IRR 0.69 [95% CI 0.62, 0.76]) and ESRD (IRR 0.67 [95% CI 0.53, 0.84]), and increased the risk of DKA (IRR 2.59 [95% CI 1.57, 4.27]) and genital infection (IRR 3.50 [95% CI 3.09, 3.95]) but not of amputation (IRR 1.23 [95% CI 1.00, 1.51]). For 1000 individuals treated over 3.5 years, SGLT2i are expected, on average, to decrease the number of deaths from 70 to 61, to prevent nine MACE, 11 HHF and two cases of ESRD, while inducing two DKA occurrences and 36 genital infections; 778 individuals are expected to avoid all the following outcomes: MACE, HHF, ESRD, amputation, DKA and genital infection.

CONCLUSIONS/INTERPRETATION: Our study is limited to aggregate data. In a population of individuals with type 2 diabetes and a high CVD risk, the cardiovascular and renal benefits of SGLT2i remain substantial despite the risk of DKA and even the hypothetical risk of amputation.

TRIAL REGISTRATION

OSF Registries: https://doi.org/10.17605/OSF.IO/J3R7Y FUNDING: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.