Diabetes, insulin use up risk of death, cardiac events in AF patients

In patients with atrial fibrillation (AF), being diabetic contributes to an increased risk of all-cause death, cardiovascular disease (CVD), myocardial infarction (MI), major bleeding, and major adverse cardiovascular events (MACE), results of the GLORIA-AF study have shown.

Additionally, AF patients with diabetes mellitus (DM) who use insulin also appear to be at greater risk of all-cause death, CVD, MI, major bleeding, and MACE.

On the other hand, insulin use combined with oral hypoglycaemic agents (OHA) “might be associated with reduced risk of these adverse outcomes in patients with AF and DM,” according to the authors, led by Dr B Huang from Liverpool Centre for Cardiovascular Science at University of Liverpool in the UK.

Huang and colleagues used the GLORIA-AF registry with 3-year follow-up to identify AF patients and analysed the link between DM and the risk of clinical adverse events, including all-cause death, major bleeding, MI, stroke, thromboembolism (TE), and MACE. MACE was characterized by a composite of stroke, major bleeding, and MI.

The authors estimated the cumulative incidence of these clinical events using Kaplan-Meier curves. In addition, they examined the relationship between DM and the risk of mortality and clinical events using multivariable Cox regression models with subgroup analyses.

Huang and colleagues included a total of 15,861 patients (mean age 70.00 years, 55 percent male, 20 percent Asian). Of these, 3,666 had DM (mean age 70.04 years, 59 percent male, 21 percent Asian). [Huang B, et al, ESC 2024]

Based on Kaplan-Meier curves, AF patients with DM showed increased cumulative risks for all outcomes: all-cause death (odds ratio [OR], 1.56, 95 percent confidence interval [CI], 1.38−1.77), CVD (OR, 1.72, 95 percent CI, 1.44−2.06), major bleeding (OR, 1.4, 95 percent CI, 1.17−1.67), stroke (OR, 1.29, 95 percent CI, 1.04−1.61), TE (OR, 1.26, 95 percent CI, 1.02−1.56), MI (OR, 1.88, 95 percent CI, 1.48−2.39), and MACE (OR, 1.61, 95 percent CI, 1.41−1.84).

The associations of DM with stroke (OR, 1.19, 95 percent CI, 0.95−1.49) and TE (OR, 1.22, 95 percent CI, 0.98−1.52) became statistically nonsignificant following adjustments for prior disease and drugs.

Insulin use

In subgroup analyses, female (OR, 1.43, 95 percent CI, 1.03−1.98; p=0.062 for interaction) and non-Asian patients (OR, 1.39, 95 percent CI, 1.06−1.82; p=0.175) with DM were at greater risk of stroke. Subgroup results for all-cause death were similar with all patients.

Among AF patients with DM, 333 (12.7 percent) took only insulin, 1,940 (73.8 percent) took OHA only, and 357 (13.6 percent) used both OHA and insulin.

Notably, patients solely managed with insulin showed an increased risk of all-cause mortality (OR, 1.82, 95 percent CI, 1.45−2.29), CVD (OR, 1.70, 95 percent CI, 1.22−2.37), major bleeding (OR, 1.54, 95 percent CI, 1.08−2.18), MI (OR, 1.72, 95 percent CI, 1.12−2.64), and MACE (OR, 1.65, 95 percent CI, 1.28−2.11). Similar results were noted in the multivariable model.

“A high percentage of patients in our study received anticoagulation (>80 percent), and 60 percent used nonvitamin K oral anticoagulants,” Huang said. “These findings underscore the importance of implementing personalized management strategies in AF patients with DM to mitigate their heightened risk of cardiovascular complications and mortality.”

Huang and colleagues also stressed the need for more data, such as DM duration and glycaemic control, to perform precise analyses of the influence of other factors associated with DM treatment.

Moreover, “the impact of other novel diabetes treatments, including SGLT2 inhibitors, remain unexplored,” Huang said.