Anemia in Patients With Diabetes and Prediabetes With Normal Kidney Function: Prevalence and Clinical Outcomes

Objective: Anemia is a known complication of diabetes mellitus (DM); however, its prevalence and prognostic relevance in patients with DM and pre-DM with normal kidney function have not been well defined. This study assessed the prevalence of anemia in patients with DM and pre-DM and evaluated its association with clinical outcomes during a 4-year follow-up period. Methods: This retrospective analysis included patients with DM and pre-DM referred to the Meir Medical Center Endocrine Institute in 2015. Patients with an estimated glomerular filtration rate (eGFR) of <60 mL/min or any other recognized cause of anemia were excluded. The risk of developing microvascular or macrovascular complications or of death during the 4-year follow-up period was determined. Results: A total of 622 patients (408 with DM and 214 with pre-DM) were included. The mean age of the patients was 64 ± 10.6 years, and 70% were women. The baseline hemoglobin A1C level was 7.1% ± 1.7% (54 mmol/mol), and the eGFR was 86.1 ± 15.3 mL/min. At the time of inclusion, 77 patients (19%) with DM and 23 (11%) with pre-DM had anemia (hemoglobin level 11.9 ± 0.8 and 11.8 ± 0.8 g/dL, respectively), compared with normal hemoglobin levels of 13.8 ± 0.9 and 13.7± 0.9 g/dL, respectively, in the others. A multivariable analysis demonstrated an inverse correlation between baseline hemoglobin (as a continuous variable) and mortality (P =.035), microvascular complications (P =.003), and eGFR decline (P <.001) but not between baseline hemoglobin and macrovascular complications (P =.567). Conclusion: This study found a significant prevalence of anemia unrelated to renal failure, both in patients with DM and pre-DM. Anemia in these patients is associated with the development of microvascular complications, eGFR decline, and mortality. These results underscore the need for intensive lifestyle and pharmacologic interventions in these patients.