Medications for adults with type 2 diabetes: a living systematic review and network meta-analysis

Abstract

Objective: To provide up-to-date evidence on key benefits, harms, and uncertainties regarding medications for adults with type 2 diabetes.

Design: Living systematic review and network meta-analysis (NMA), using frequentist random effects and GRADE (grading of recommendations, assessment, development and evaluation) approaches. Updates are planned at least two times a year.

Data sources: Medline and Embase, searched up to 31 July 2024 for the current iteration.

Study selection: Randomised controlled trials of at least 24 weeks comparing one or more medications with standard treatment, placebo, or each other.

Results: The systematic review and NMA includes 493 168 participants from 869 trials (adding 53 trials since October 2022) reporting data for 13 drug classes (63 drugs) and 26 outcomes of interest. Regarding benefits, moderate to high certainty evidence confirms the well established cardiovascular and kidney benefits of sodium-glucose cotransporter-2 (SGLT-2) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1RAs), and finerenone (the last for patients with established chronic kidney disease). The most effective drugs in reducing body weight were tirzepatide (mean difference (MD) -8.63 kg (95% confidence interval -9.34 to -7.93); moderate certainty) and orforglipron (MD -7.87 kg (-10.24 to -5.50); low certainty), followed by eight other GLP-1RAs (high to moderate certainty). Absolute benefits of medications vary substantially depending on the baseline risk of cardiovascular and kidney outcomes; risk-stratified absolute effects of medications are summarised using an interactive multiple comparisons tool (https://matchit.magicevidence.org/250709dist-diabetes/#!/). Regarding medication-specific harms, SGLT-2 inhibitors increase genital infections (odds ratio (OR) 3.29 (95% CI 2.88 to 3.77); high certainty) and ketoacidosis due to diabetes (OR 2.08 (1.45 to 2.99); high certainty), and probably increase amputations (OR 1.27 (1.01 to 1.61); moderate certainty); tirzepatide and GLP-1RAs probably increase severe gastrointestinal events (most increased risk with tirzepatide (OR 4.21 (1.87 to 9.49); moderate certainty)); finerenone increases severe hyperkalaemia (OR 5.92 (3.02 to 11.62); high certainty); and thiazolidinediones increase major osteoporotic fractures and probably increase hospitalisation for heart failure. Sulfonylureas, insulin, and dipeptidyl peptidase-4 inhibitors probably increase the risk of severe hypoglycaemia. There is low to very low certainty evidence for effects on other diabetes-related complications, including neuropathy and visual impairment. Despite interest in the issue, there is uncertainty about whether GLP-1RAs may reduce dementia (OR 0.92 (0.83 to 1.02); low certainty).

Conclusions: This living systematic review provides a comprehensive summary of the cardiovascular, kidney, and weight loss benefits, as well as medication-specific harms of medications for adults with type 2 diabetes, including effects of SGLT-2 inhibitors, GLP-1RAs, finerenone and tirzepatide.

Systematic review registration: PROSPERO number: CRD42022325948. A more detailed protocol is available at https://data.aliveevidence.org/records/q02rv-km486.

Readers' notes: This article is the first version of a living systematic review. It is linked to a living BMJ Rapid Recommendation and other living clinical practice guidelines, presenting risk stratified recommendations for patients with type 2 diabetes at lower, moderate, and higher risk of cardiovascular and kidney complications. The latest evidence will be made available via the BMJ Rapid Recommendation and via an interactive GRADE evidence summary (MATCH-IT: https://matchit.magicevidence.org/250709dist-diabetes/#!/). Major updates will be published in The BMJ.