Diabetes guidelines recommend sodium-glucose transport protein 2 (SGLT2) inhibitors to reduce kidney disease progression in patients with type 2 diabetes (T2D) and moderate-to-severe albuminuric kidney disease on the basis of renal outcomes trials, such as CREDENCE and DAPA-CKD. However, these trials did not include patients who are at low risk for kidney disease progression.
Mozenson and colleagues published a post hoc analysis of the DECLARE-TIMI 58 trial and focused on patients with low kidney risk. They demonstated that dapagliflozin slowed the progression of kidney disease in patients with T2D at high cardiovascular risk, including those who are at low risk for kidney progression. The absolute benefit for slowing kidney progression was much lower in patients with low kidney risk compared with those who are at high or very high risk (number needed to treat 177 vs 13-23). Though dapagliflozin does provide kidney protection across a spectrum of patients with kidney risk, clinicians should consider the level of risk when starting an SGLT2 inhibitor for slowing kidney disease.
SGLT2 inhibitor outcome trials and meta-analyses have mainly shown neutral results for ischemic stroke, except for sotagliflozin vs placebo in the SCORED trial. In this trial, sotagliflozin was shown to reduce total stroke. Recently, in a retrospective longitudinal cohort study of patients with T2D in Taiwan, Lin and colleagues have shown a significant reduction in new onset stroke among those who use SGLT2 inhibitor compared with those who don't. A 15% relative risk reduction in stroke was shown in an analysis that adjusted for age, sex, and duration of T2D, with a similar reduction in a propensity score-matched analysis. Although limited by its observational design, this study suggests that further research should be continued regarding the impact of SGLT2 inhibitors on stroke outcomes.
Severe hypoglycemia is a serious complication of insulin and insulin secretagogue therapy. There have been few studies regarding the association between long-term glycemic variability of A1c and fasting plasma glucose (FPG) and the risk for severe hypoglycemia. Long and colleagues performed a post hoc analysis of the ACCORD study and found that both A1c and FPG variability were associated with a greater risk for severe hypoglycemia in T2D, with FPG being a more sensitive indicator than is A1c variability. Clinicians need to be aware that A1c and FPG variability in insulin- or insulin secretagogue–treated patients with T2D places them at greater risk for severe hypoglycemia and such variability should be considered a potential target of treatment.
Although a higher mean A1c has been linked to diabetes microvascular and macrovascular complications, there is a paucity of data comparing mean A1c and A1c variability and diabetes complications. In a prospective study from Taiwan, Wu and colleagues demonstrated that both mean A1c and A1c variability predicted most diabetes-related complications, with mean A1c being more effective at predicting retinopathy and A1c variability being more effective at predicting a decline in kidney function and cardiovascular and total mortality. Perhaps physicians need to pay more attention to A1c variability and not just the mean A1c over time when assessing an individual and their overall risk for diabetes complications.