Author: Dr. Alison McAllister
Men's Heart Health and Testosterone: Separating Fact from Fiction
In recent times, the media has been abuzz with discussions on men's heart health and the role of testosterone therapy. Reports have raised concerns about potential links between testosterone treatment and heart attacks, prompting physicians to reevaluate the use of testosterone supplementation in men. To gain a better understanding of this complex issue, it's essential to delve deeper into the scientific study that has triggered these debates (referenced at the end of this post) (1).
The study in question examined 55,593 men who initiated testosterone therapy. Among these men, some were over 65 years old, while a smaller group was under 65. The study focused on two critical subgroups: those with pre-existing cardiovascular disease and those without. Additionally, the research looked into men who were not using testosterone but were taking phosphodiesterase type 5 inhibitors, such as sildenafil, tadalafil, or Viagra. In essence, the study was an extensive analysis of insurance data.
Here's what the study found:
Group 1 - Men over 65 years old with heart disease had a two-fold increased risk of myocardial infarction (MI).
Group 2 - Men over 65 years old without known cardiovascular disease (2,047 individuals) had a two-fold increased risk of MI (eight cases).
Group 3 - Men under 65 years old with cardiovascular disease (4,006 participants) had a two to three-fold increased risk of MI (21 cases).
Group 4 - Men under 65 years old without known cardiovascular disease had no increased risk of MI.
Group 5 - Men taking phosphodiesterase type 5 inhibitors showed no increase in MIs.
What can we infer from this study, and what questions does it raise?
1. Age Matters: Age appears to be a better predictor of cardiovascular health than a patient's prior medical diagnoses.
2. Sexual Activity and MI: The study suggests that sexual activity alone is not the primary trigger for the increase in MI rates, as there was no increase in MIs among men using circulation-boosting sexual performance drugs.
3. Younger Men Benefit: Men under the age of 65 without known cardiovascular disease are unlikely to experience an MI when starting testosterone therapy. This is particularly significant as this demographic shows the highest growth in testosterone usage.
1. What Causes the MI Risk? What is it about testosterone therapy that increases the risk of MI? Is it the rise in estrogen, produced when testosterone is metabolized by aromatase? Is it a change in cardiovascular tone? Does the increase in libido lead to more sexual activity than typically observed with only phosphodiesterase type 5 inhibitors?
2. Long-Term Effects: What happens to men beyond the initial 90 days if they continue testosterone therapy?
3. Delivery Methods: Does altering the mode of testosterone supplementation (topical, injection, pellet, sublingual) influence a patient's cardiovascular outcomes?
4. Dosage Matters: Does the dosage of testosterone make a difference in the risk of MI?
Dr. Alison McAllister, one of our clinical consultants, shares some insights from the study:
- Cardiovascular disease is prevalent, and age, rather than medical history, is a better indicator of cardiovascular health.
- The study didn't find an increase in non-fatal MIs among men using phosphodiesterase type 5 inhibitors, which may be because these drugs facilitate erections but not necessarily libido. Men using testosterone therapy may be more inclined to engage in sexual activity and increased physical exercise.
- Estrogen levels and dosage are critical considerations. Administering testosterone in ways that don't elevate clotting risks, coagulation, or lead to changes in blood indices like RBC counts, hemoglobin, or hematocrit may not increase the risk of MI. Lower-dose topical testosterone therapies combined with aromatase inhibitors could be a viable approach.
In conclusion, this study emphasizes the need for caution when prescribing testosterone to men over 65, encouraging a gradual return to physical activities rather than a sudden surge in exercise. Dosing at physiological levels, monitoring estrogen levels, and having open discussions with patients are essential. Importantly, the study did not find an increased risk of MI among men under 65 with no reported cardiovascular disease, which indicates that testosterone support can be safely discussed with this group.
These questions raised by the study highlight the importance of further clinical trials to uncover more answers. This study isn't the first to suggest these findings, and it is hoped that it will inspire more research to shed light on this complex topic.
See the original of this blog on ZRT Lab Website, Blog section.
Author: Dr. Alison McAllister
Men's Heart Health and Testosterone
(1) W. D. Finkle, S. Greenland, G. K. Ridgeway, J. L. Adams, M. A. Frasco, M. B. Cook, J. F. Fraumeni, Jr., and R. N. Hoover. Increased risk of non-fatal myocardial infarction following testosterone therapy prescription in men. PLoS ONE 9 (1):1-7, 2014.
(2) Schulman SP, Becker LC, Kass DA, Champion HC, Terrin ML, Forman S, Ernst KV, Kelemen MD, Townsend SN, Capriotti A, Hare JM, Gerstenblith G. L-arginine therapy in acute myocardial infarction: the Vascular Interaction With Age in Myocardial Infarction (VINTAGE MI) randomized clinical trial. JAMA. 2006;295(1):58-64.