Testosterone replacement therapy (TRT) in hypogonadal men may reduce anemia, a new study suggests.

“After 54 weeks, testosterone undecanoate decreased the prevalence of anemia and components of the metabolic syndrome,” Li Tao Zhang, MD, and colleagues from Chonbuk National University in Jeonju, South Korea, concluded in The Journal of Urology.

The investigators studied 58 men aged 18–80 years from their hospital with a serum total testosterone level below 2.35 ng/mL and at least mild symptoms of testosterone deficiency syndrome. Most had never received TRT, although some discontinued TRT in the 6 months before the study. Each patient then received an injection of 1,000 mg testosterone undecanoate at 0, 6, 18, 30, 42, and 54 weeks.

Continue Reading

About half of patients had comorbidities such as hypertension, treated type 2 diabetes, and coronary artery disease. Researchers excluded patients with prostate cancer, kidney disease, and uncontrolled diabetes.

Results showed that testosterone undecanoate normalized total and free testosterone levels. Concurrently, hemoglobin and hematocrit significantly increased by an average of 2.46 g/dL and 3.03%, respectively. The prevalence of anemia fell significantly from 29.6% to 10%. Among patients with anemia, erythropoietin levels increased significantly. All of the associations indicated that low testosterone contributes to anemia, the investigators suggested. Testosterone plays an important role in erythropoiesis, and it may reduce inflammation; it does not appear to help iron recycling.

Total cholesterol decreased from 165.89 to 153.80 mg/dL. Meanwhile, whole blood viscosity and hematocrit increased and stabilized after 18 weeks. The findings suggest that TRT may not increase risk of cardiovascular disease.

TRT’s benefits did not differ by patient age. Future studies are needed to clarify whether TRT affects cardiovascular health, given the study’s small sample size, short follow up, and lack of randomization.