Meta-analyses of s odium-glucose cotransporter 2 inhibitor (SGLT2i) outcome trials have shown reductions in all-cause and cardiovascular mortality, but dipeptidyl peptidase 4 inhibitors (DPP4i) have been neutral for these outcomes. In a Taiwanese retrospective cohort study, Chung and colleagues compared 53,264 pairs of propensity-matched patients with type 2 diabetes who were treated with either an SGLT2i or DPP4i. They not only reported relative risk reductions of 34% and 32% for all-cause death and cardiovascular death, respectively, but also a reduction in cancer death of 27% and a reduction in noncancer, noncardiovascular death of 38%. Although limited by its retrospective, observational design, the finding of a benefit of SGLT2i treatment on both cancer death and noncancer, noncardiovascular death would benefit from further research.
In another large Taiwanese retrospective cohort study with propensity matching, Chan and colleagues compared patients treated with SGLT2i, DPP4i, and g lucagon-like peptide 1 receptor agonists (GLP-1RA), with a main study outcome of new-onset atrial fibrillation (AF). They noted that SGLT2i treatment was associated with a 10% and 36% lower risk for AF compared with DPP4i and GLP-1RA treatment, respectively. These results are consistent with meta-analyses of SGLT2i outcome trials that have demonstrated reductions in AF with SGLT2i vs placebo. Perhaps it is time to recognize that another clinical benefit of the SGLT2i class is the reduction in risk for AF.
Although GLP-1RA have been linked to an increased risk for gallbladder-related events in many studies, there has been little data suggesting an increased risk with DPP4i. He and colleagues have published a pairwise meta-analysis of 82 randomized clinical trials and found that DPP4i compared with placebo or nonincretin drugs increased the risk for gallbladder or biliary diseases by 1.22-fold, with 11 more events per 10,000 person years. In a network meta-analysis of 184 randomized trials, they also found that DPP4i treatment increased the risk for gallbladder or biliary diseases compared with SGLT2i but not compared with GLP-1RA. This was the first meta-analysis to systematically study the association between DPP4i and gallbladder-related diseases. Although the absolute risk is small, clinicians need to be aware of this link and consider this adverse effect when deciding about the risks vs benefits of DPP4i treatment.
Individuals with obesity and prediabetes are at greater risk for type 2 diabetes. Trials of lifestyle modification and antiobesity agents have shown that restoration to normoglycemia can occur with weight loss. Phase 3A studies of the antiobesity agent semaglutide (2.4 mg/week) included 3375 individuals with prediabetes across three trials. In a post hoc analysis of these patients with prediabetes, Perreault and colleagues found that after 68 weeks of treatment, there was a much higher likelihood of normoglycemia with 2.4 mg/week of semaglutide compared with placebo. Though definite conclusions are limited owing to the post hoc nature of this analysis, these results make it very likely that the ongoing STEP 10 trial of 2.4 mg semaglutide vs placebo (201 participants with obesity and prediabetes) will probably show a significant benefit on the primary outcome of change to normoglycemia.