From the Guidelines
Regular laboratory monitoring for patients on Testosterone Replacement Therapy (TRT) should include testosterone levels, hematocrit, prostate-specific antigen (PSA), and liver function tests, with the frequency of testing guided by the patient's age, symptoms, and response to therapy.
Key Laboratory Tests for TRT Follow-Up
- Testosterone levels should be checked 2-3 months after initiating therapy and then every 6-12 months to ensure levels are within the therapeutic range (typically 400-700 ng/dL) 1.
- Hematocrit should be monitored at baseline, 3-6 months after starting treatment, and then annually, as TRT can increase red blood cell production and potentially cause erythrocytosis (a hematocrit >54% may require dose adjustment or discontinuation) 1.
- For men over 40, PSA testing should be performed at baseline and then annually to monitor for prostate changes, with consideration of more frequent testing based on individual risk factors and shared decision-making with the clinician 1.
- Liver function tests are recommended annually, particularly for those using oral testosterone formulations.
Rationale for Monitoring
These tests are crucial because TRT affects multiple body systems and can potentially exacerbate underlying conditions like prostate cancer, sleep apnea, or cardiovascular disease. Monitoring allows for timely dose adjustments or discontinuation if adverse effects occur. The choice of tests and frequency of monitoring should be individualized based on the patient's specific needs and risk factors, with a focus on minimizing potential harms while maximizing benefits 1.
From the Research
Laboratory Tests for Follow-up on Testosterone Replacement Therapy (TRT)
To monitor the effectiveness and potential risks of TRT, several laboratory tests are recommended for follow-up. These tests include:
- Prostate-specific antigen (PSA) levels: PSA levels should be assessed every 6-12 months to monitor for potential prostate cancer, as suggested by 2.
- Testosterone levels: Total testosterone levels should be measured regularly to ensure they are within the normal range, as indicated by 2, 3, 4.
- Hematocrit: Hematocrit levels should be monitored to assess for potential polycythemia, a condition characterized by an increased red blood cell count, as mentioned in 2.
- Lipid profile: Lipid profiles should be assessed to monitor for changes in cholesterol levels, as suggested by 2, 3.
- Liver function tests (LFTs): LFTs should be performed to monitor for potential liver damage, as mentioned in 2.
- Body mass index (BMI): BMI should be calculated to assess for changes in body composition, as indicated by 5, 4.
- Augmentation index (AI) and reactive hyperemia index (RHI): These tests can be used to assess endothelial function, as suggested by 3.
Special Considerations
Men with a high burden of systemic illness, such as diabetes, cardiovascular disease, and sleep apnea, may require more frequent monitoring and adjustments to their treatment plan, as indicated by 5. Additionally, men with HIV/AIDS may require special consideration when initiating TRT, as suggested by 4.
Prostate Biopsy
Men with hypogonadism who have a clinical indication for biopsy, such as an elevated PSA level or abnormal digital rectal exam, should undergo prostate biopsy to rule out prostate cancer, as recommended by 6.