Background: Newer diabetes medications may have beneficial effects on mortality, cardiovascular outcomes, and renal outcomes.
Purpose: To evaluate the effectiveness, comparative effectiveness, and harms of sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP1) agonists, dipeptidyl peptidase-4 (DPP4) inhibitors, and long-acting insulins as monotherapy or combination therapy in adults with type 2 diabetes mellitus (T2DM).
Data sources: MEDLINE and EMBASE for randomized controlled trials (RCTs) published from 2010 through January 2023.
Study selection: RCTs lasting at least 52 weeks that included at least 500 adults with T2DM receiving eligible medications and reported any outcomes of interest.
Data extraction: Data were abstracted by 1 reviewer and verified by a second. Independent, dual assessments of risk of bias and certainty of evidence (CoE) were done.
Data synthesis: A total of 130 publications from 84 RCTs were identified. CoE was appraised using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria for direct, indirect, and network meta-analysis (NMA); the highest CoE was reported. Compared with usual care, SGLT2 inhibitors and GLP1 agonists reduce all-cause mortality (high CoE) and major adverse cardiovascular events (MACE) (moderate to high CoE), SGLT2 inhibitors reduce progression of chronic kidney disease (CKD) and heart failure hospitalizations and GLP1 agonists reduce stroke (high CoE), and SGLT2 inhibitors reduce serious adverse events and severe hypoglycemia (high CoE). The threshold for minimally important differences, which was predefined with the American College of Physicians Clinical Guidelines Committee, was not met for these outcomes. Compared with usual care, insulin, tirzepatide, and DPP4 inhibitors do not reduce all-cause mortality (low to high CoE). Compared with insulin, SGLT2 inhibitors and GLP1 agonists reduce all-cause mortality (low to moderate CoE). Compared with DPP4 inhibitors, GLP1 agonists reduce all-cause mortality (moderate CoE). Compared with DPP4 inhibitors and sulfonylurea (SU), SGLT2 inhibitors reduce MACE (moderate to high CoE). Compared with SU and insulin, SGLT2 inhibitors and GLP1 agonists reduce severe hypoglycemia (low to high CoE).
Limitations: Infrequent direct comparisons between drugs of interest; sparse data for NMA on most outcomes; possible incoherence due to differences in baseline patient characteristics and usual care; insufficient data on predefined subgroups, including demographic subgroups, patients with prior cardiovascular disease, and treatment-naive persons.
Conclusion: In adults with T2DM, SGLT2 inhibitors and GLP1 agonists (but not DPP4 inhibitors, insulin, or tirzepatide) reduce all-cause mortality and MACE compared with usual care. SGLT2 inhibitors reduce CKD progression and heart failure hospitalization and GLP1 agonists reduce stroke compared with usual care. Serious adverse events and severe hypoglycemia are less frequent with SGLT2 inhibitors and GLP1 agonists than with insulin or SU.
Primary funding source: American College of Physicians. (PROSPERO: CRD42022322129).