Intermediate Hyperglycemia Linked to Higher Mortality Risk in Premature CAD Patients Undergoing PCI: Study

The study, published in Reviews in Cardiovascular Medicine, highlights the need for active glucose-lowering therapy in these patients.

Premature coronary artery disease, defined as CAD in individuals younger than 55, poses significant challenges due to its early onset and aggressive nature. PCI, a common procedure to restore blood flow in blocked coronary arteries, is frequently used to treat these patients. However, new evidence suggests that intermediate hyperglycemia—a condition where blood glucose levels are elevated but not high enough to be classified as diabetes—may significantly impact outcomes for these patients.

It remains unclear whether intermediate hyperglycemia affects the risk of mortality in premature CAD patients undergoing PCI. Considering this, Ziyou Zhou, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China, and colleagues aimed to assess the prevalence of intermediate hyperglycemia and its effect on long-term all-cause death in premature CAD patients treated with PCI.

For this purpose, the researchers retrospectively included 14,585 premature CAD patients undergoing PCI from 2007 to 2020. Patients were categorized based on their hemoglobin A1c (HbA1c) levels into three groups: normal glycemia (< 6%), intermediate hyperglycemia (6%–6.5%), and hyperglycemia (≥ 6.5%).

All-cause mortality during follow-up was defined as the primary outcome, and Cox proportional hazards regression analysis was employed to evaluate the relationship between glycemic status and this outcome.

The following were the key findings of the study:

• Among 14,585 premature CAD patients undergoing PCI (mean age 43.6 ± 7.6 years, 28.1% female), 19.6% were diagnosed with intermediate hyperglycemia.
• Over a median follow-up of 4.62 years, patients with hyperglycemia were correlated with higher risk (hazard ratio [HR] 1.35), while patients with intermediate hyperglycemia were associated with intermediate mortality risk from all causes (HR 1.17).

The study confirmed that compared to normal glycemia, intermediate hyperglycemia is associated with a 17% increased risk of all-cause mortality, while hyperglycemia corresponds to a 35% higher risk in premature CAD patients undergoing PCI.

"These findings underscore the importance of early HbA1c monitoring in this population to prevent adverse outcomes. Active management of blood glucose levels and setting lower HbA1c targets should be considered for these patients to improve their prognosis," the researchers wrote.

The study's limitations include its retrospective design, potential confounding factors, and focus solely on all-cause mortality due to data constraints.

"Further prospective studies are needed. Additionally, HbA1c variability was not assessed, and hyperglycemia was determined based on baseline levels, highlighting the need for more comprehensive research," they concluded.

Reference:

Zhou, Ziyou, et al. "Intermediate Hyperglycemia Increases the Risk of All-Cause Mortality in Premature Coronary Artery Disease Patients Undergoing Percutaneous Coronary Intervention." Reviews in Cardiovascular Medicine, vol. 24, no. 12, 2023, p. 352.