Meta-analysis of 6,525 cardiac patients: intensive glucose control linked to fewer strokes

A systematic review and meta-analysis in Frontiers in Cardiovascular Medicine pooled sixteen unique randomized trials with 6,525 adult participants. The trials compared an intensive glycemic-control protocol with a conventional one in adults undergoing cardiac surgery or experiencing an acute cardiac condition. The authors searched PubMed, Embase, the Cochrane Library and Web of Science through 21 December 2024. frontiersin.orgFrontiers in Cardiovascular Medicinefrontiersin.orgOpen source ↗

Hyperglycemia is common during cardiac surgery and acute cardiac illness, and the balance between benefits and harms of lower glucose targets has remained uncertain. The review was registered in PROSPERO under CRD42023418963.

Stroke and myocardial infarction

Stroke and myocardial infarction were the primary outcomes. Intensive glycemic control was associated with fewer strokes (risk ratio 0.36, 95% confidence interval 0.23–0.55; heterogeneity 0%).

For myocardial infarction the association was absent: the risk ratio was 0.96 (95% confidence interval 0.82–1.13; heterogeneity 9%). frontiersin.orgFrontiers in Cardiovascular Medicinefrontiersin.orgOpen source ↗ Tests for interaction by cardiac condition were not significant.

Infection, kidney function and other outcomes

Among secondary outcomes, intensive control was associated with a lower risk of infection (risk ratio 0.50, 95% confidence interval 0.37–0.67; heterogeneity 0%) and of acute renal dysfunction (risk ratio 0.73, 95% confidence interval 0.57–0.94).

No association was found with 30-day mortality (risk ratio 0.93, 95% confidence interval 0.70–1.22). Intensive care unit stay differed by a mean of 3.03 h (95% confidence interval −0.84 to 6.89), and hospital stay by a mean of −0.02 days (95% confidence interval −0.50 to 0.46); neither difference was significant. Atrial fibrillation was lower after cardiac surgery other than coronary artery bypass grafting, but not after bypass grafting.

The authors concluded that lower-target protocols may reduce selected complications, particularly stroke and infection, but that the evidence is heterogeneous and does not support routine glucose targets below current critical-care recommendations. They state that treatment should prioritize avoiding both marked hyperglycemia and hypoglycemia, with protocolized monitoring and individualized targets. frontiersin.orgFrontiers in Cardiovascular Medicinefrontiersin.orgOpen source ↗

The authors also note that larger contemporary trials reporting hypoglycemia and glycemic variability are required.