Hemoglobin A(1c) levels and mortality in the diabetic hemodialysis population: findings from the Dialysis Outcomes...

Area of Science:

• Nephrology
• Endocrinology
• Clinical Epidemiology

Background:

• Lowering hemoglobin A1c (HbA1c) to below 7% is recommended to reduce microvascular complications in diabetes.
• The optimal HbA1c target for patients with kidney failure on hemodialysis remains unclear.
• This study investigates the association between HbA1c levels and mortality in a large international cohort of hemodialysis patients.

Purpose of the Study:

• To evaluate the relationship between HbA1c levels and mortality in patients undergoing hemodialysis.
• To determine if current HbA1c targets are appropriate for patients with diabetes and kidney failure.

Main Methods:

• A prospective cohort study included 9,201 hemodialysis patients with type 1 or type 2 diabetes from 12 countries (Dialysis Outcomes and Practice Patterns Study 3 and 4, 2006-2010).
• HbA1c levels were measured within the first 8 months of study entry.
• Cox regression analysis was used to assess the association between HbA1c and mortality, adjusting for numerous potential confounders.

Main Results:

• The association between HbA1c and mortality exhibited a U-shaped pattern.
• Compared to an HbA1c of 7-7.9%, mortality risk was higher for levels below 5% (HR 1.35) and 6-6.9% (HR 1.21), as well as for levels ≥9.0% (HR 1.38).
• Diabetes medications were prescribed for only 35% of patients with HbA1c <6% and not prescribed for 29% with HbA1c ≥9%.

Conclusions:

• HbA1c levels are a strong predictor of mortality in hemodialysis patients with diabetes.
• Mortality risk increases as HbA1c levels deviate from the 7-7.9% range, suggesting higher target HbA1c values may be appropriate for this population.
• Adjusting glucose-lowering medication strategies to target HbA1c levels within this broader range could potentially improve outcomes for hemodialysis patients.