Real-world cohort: SGLT-2 inhibitors linked to lower kidney failure risk than GLP-1 RAs

The study

This paper, published in Diabetes, Obesity & Metabolism, compares two drug classes in adults with type 2 diabetes (T2D): sodium-glucose cotransporter-2 inhibitors (SGLT-2i) and glucagon-like peptide-1 receptor agonists (GLP-1 RA). The authors ran a retrospective, new-user cohort study. They used the TriNetX global federated health research network.

Patients started an SGLT-2i or a GLP-1 RA between 2018 and 2023. After propensity score matching, there were 249 237 pairs, or 498 474 patients in total.

The primary outcome was a composite of kidney failure, dialysis, kidney transplantation or all-cause mortality. Secondary outcomes were composite cardiovascular events, mortality and safety.

What they found

SGLT-2i initiation was associated with a lower risk of the primary composite than GLP-1 RA initiation (HR 0.87, 95% CI 0.85-0.89).

For the kidney-specific part of the composite (kidney failure, dialysis or kidney transplantation), the risk was lower with SGLT-2i (HR 0.74, 95% CI 0.71-0.78). All-cause mortality was also lower with SGLT-2i (HR 0.90, 95% CI 0.88-0.93).

The composite cardiovascular outcome included myocardial infarction, stroke, acute heart failure, cardiogenic shock, cardiac arrest or death. The authors called it broadly comparable between groups (HR 0.98, 95% CI 0.97-1.00). The abstract does not report a formal non-inferiority or equivalence test for this outcome.

The abstract names safety as a secondary outcome but does not give any safety results.

How much weight to give it

The authors describe the finding as an association. That is the right level. This is an observational, retrospective study. Propensity score matching can balance the characteristics that were measured, but it cannot remove differences that were not recorded. Doctors may choose one drug class over the other for reasons that are not captured in health records. The abstract does not say which characteristics were matched.

The size of the cohort is a strength. It gives narrow confidence intervals. But a large sample does not remove bias from the design.

The abstract also does not report the length of follow-up, the funding source, or the results for the individual cardiovascular components. The primary composite mixes kidney events with all-cause death, so the result partly reflects mortality. Read the kidney-specific and mortality results separately.

For your clinic

The authors say these associations may inform individualised treatment selection in adults with T2D. As an observational study, it does not establish that one class should be preferred over the other.

The cardiovascular composite was broadly comparable between groups (HR 0.98, 95% CI 0.97-1.00). No formal equivalence or non-inferiority test is reported in the abstract.

The abstract gives no safety results, so safety cannot be judged from it.

Before changing practice, read the full paper. Check how the groups were matched, how long patients were followed, and what the safety results show. Compare the findings with current guidelines.