Testosterone replacement therapy carries a cardiovascular reputation problem that outdated data created and newer trials have mostly settled — here's what the evidence actually shows and how a clinician should monitor your heart risk if you start treatment.
- The 2023 TRAVERSE trial found no increased rate of major adverse cardiac events in hypogonadal men on testosterone therapy versus placebo over a median of 22 months.
- The FDA's decade-long cardiovascular warning was based on two flawed 2013-2014 studies, one with a retracted math error.
- Low testosterone itself correlates with metabolic syndrome, visceral fat, and abnormal lipids — independent cardiovascular risk drivers.
- Hematocrit above 54% is the threshold most clinicians treat as a hard stop or dose reduction trigger.
- Blood pressure and hematocrit should be rechecked at 90 days, not at the annual physical, since levels shift fastest in the first three to six months.
- Full metabolic response to therapy typically takes 6 to 12 months to stabilize.
TL;DR
The 2023 TRAVERSE trial, the largest testosterone-cardiovascular safety study to date, found no increased rate of major adverse cardiac events in hypogonadal men on testosterone therapy versus placebo over a median of 22 months. Low testosterone itself correlates with higher rates of metabolic syndrome, visceral fat, and abnormal lipids — all cardiovascular risk drivers on their own. Verdict: testosterone therapy is not the cardiac hazard older studies implied, but it still requires baseline labs, hematocrit monitoring, and blood pressure tracking before and during treatment. Men considering testosterone and cardiovascular health questions in 2026 should treat this as a monitored medical protocol, not a supplement decision.
Why this matters
For over a decade, testosterone therapy carried an FDA-mandated cardiovascular warning label based on two flawed studies from 2013 and 2014 — one with a math error in its own conclusion, later retracted in part. That warning shaped a generation of physician hesitancy. Meanwhile, low testosterone was quietly correlating with the exact conditions that raise heart attack and stroke risk: insulin resistance, higher LDL, more visceral fat, and elevated blood pressure.
TRAVERSE changed the conversation. Enrolling over 5,000 men aged 45 to 80 with pre-existing cardiovascular risk factors, it found testosterone therapy performed no worse than placebo on major adverse cardiac events. That doesn't mean testosterone therapy is risk-free — it means the risk profile depends on how treatment is dosed and monitored, not on the hormone itself. Hormone optimization for men over 50 covers how protocols shift as baseline risk changes with age.
That doesn't mean testosterone therapy is risk-free — it means the risk profile depends on how treatment is dosed and monitored, not on the hormone itself.
What you'll need
- A complete metabolic panel, lipid panel, and hemoglobin A1c drawn within the last 90 days
- A baseline hematocrit and hemoglobin — testosterone therapy raises red blood cell count and this is the marker most tied to clot risk
- Blood pressure readings from at least two separate occasions, not one office visit
- A total and free testosterone level drawn in the morning, when levels peak
- A clinician willing to recheck labs at 3, 6, and 12 months, not just prescribe and disappear
- Family history of heart disease, stroke, or clotting disorders before your first visit
Low testosterone symptoms in men: what labs actually show walks through which numbers actually indicate a deficiency worth treating versus normal age-related decline.
The process: how testosterone and cardiovascular monitoring should work
1. Establish your baseline cardiovascular risk profile
Before any prescription, your clinician should know your LDL, HDL, triglycerides, fasting glucose, and blood pressure trend — not a single reading. This accomplishes two things: it identifies whether existing cardiovascular risk factors need treatment on their own, and it gives you a comparison point six months into therapy. Men with untreated hypertension or LDL above 160 mg/dL should address those first. Common mistake: starting testosterone while ignoring an already-elevated blood pressure reading, then attributing a later spike to the hormone.
2. Confirm the diagnosis with two separate morning draws
A single low testosterone reading isn't a diagnosis. Guidelines call for two morning draws, typically below 300 ng/dL, alongside symptoms like low energy, reduced libido, or loss of muscle mass. This step matters because treating a transient dip — caused by poor sleep, acute illness, or lab timing — exposes you to therapy you didn't need. Expected outcome: a confirmed total testosterone level under 300 ng/dL on two occasions, paired with at least one clinical symptom.
3. Choose a delivery method matched to your monitoring plan
Injectable testosterone cypionate produces peak-and-trough swings that can spike hematocrit faster than topical gels or pellets. Weekly or twice-weekly injections smooth this curve compared to older bi-weekly dosing. Best testosterone therapy options for men in 2026 breaks down injections, gels, and pellets against dosing consistency. Common mistake: choosing pellets for convenience without accounting for the 3-4 month window where dose can't be adjusted if hematocrit climbs.
4. Recheck hematocrit at 90 days, not annually
Hematocrit above 54% is the threshold most clinicians treat as a hard stop or dose reduction trigger, since elevated red blood cell concentration raises clot risk. Checking at the standard annual physical misses the window where levels climb fastest — usually the first three to six months on therapy. Expected outcome: hematocrit staying under 52% with a dose that still resolves your symptoms.
Hematocrit above 54% is the threshold most clinicians treat as a hard stop or dose reduction trigger, since elevated red blood cell concentration raises clot risk — and checking only at the annual physical misses the window where levels climb fastest.
5. Track blood pressure monthly for the first quarter
Testosterone can cause modest fluid retention in some men, nudging blood pressure up by 3-5 mmHg systolic in the early months. This matters because a small bump compounds with any existing hypertension. Expected outcome: blood pressure staying within 10 points of your pre-treatment baseline; if it doesn't, dose or delivery method needs adjustment before continuing.
6. Reassess lipids and A1c at the 6-month mark
Testosterone therapy often improves insulin sensitivity and can lower fat mass, which sometimes improves lipid panels rather than worsening them — but this varies by individual. This step accomplishes a full-picture check: is the therapy improving your metabolic markers alongside your symptoms, or is something moving the wrong direction. Medical weight loss for men with metabolic syndrome covers how testosterone optimization and weight management overlap for men carrying both diagnoses.
7. Decide on long-term continuation based on data, not comfort
By 12 months, you should have three data points on hematocrit, blood pressure, and lipids. Continuation makes sense when symptoms have improved and cardiovascular markers are stable or better. Common mistake: continuing a protocol on symptom improvement alone while hematocrit trends upward unchecked for a full year.
Troubleshooting
Common issues and fixes
Based on the monitoring checkpoints above
| Issue | Recommended action |
|---|---|
| Hematocrit climbing above 52% | Reduce dose, switch to more frequent smaller injections, or consider a therapeutic phlebotomy if it exceeds 54% |
| Blood pressure rising more than 10 points | Check for fluid retention, reassess sodium intake, and consider dose reduction before adding an antihypertensive |
| No symptom improvement after 3 months | Recheck free testosterone; some men need dose titration, others may have a non-hormonal cause for fatigue or low libido |
| New acne or mood irritability | Often a sign of dose too high or too frequent; smoothing injection frequency usually resolves it faster than dose reduction alone |
| LDL rising instead of falling | Testosterone response varies; this isn't automatic and may require separate lipid management alongside therapy |
| Sleep apnea symptoms worsening | Testosterone can exacerbate undiagnosed sleep apnea, which independently raises cardiovascular risk; a sleep study should be considered before continuing |
Tools and resources
- Baseline and quarterly lab panels through a clinician who orders and interprets results directly, rather than a lab-only service
- How to read your hormone lab results for understanding what each number on your panel actually means
- A home blood pressure cuff for monthly checks between visits
- Testosterone replacement therapy for men with low testosterone for a fuller breakdown of who qualifies for treatment
- A record of your family cardiovascular history to bring to your first consultation
What to do next
If your total testosterone has come back under 300 ng/dL twice and you're weighing therapy against cardiovascular risk factors already on your chart, the next move is a full baseline panel — not another symptom questionnaire. How to prepare for your first hormone consultation covers what to bring and what questions to ask before your clinician writes a protocol.
FAQ
Does testosterone therapy cause heart attacks? The 2023 TRAVERSE trial, involving over 5,000 men with cardiovascular risk factors, found no increased rate of heart attack, stroke, or cardiovascular death compared to placebo over a median follow-up of 22 months. Earlier warnings from 2013-2014 studies have not held up under larger, better-designed trials.
Is low testosterone itself a cardiovascular risk factor? Low testosterone correlates with higher rates of metabolic syndrome, visceral fat, and abnormal lipid panels — all independent cardiovascular risk drivers. Correlation isn't causation, but untreated low testosterone rarely improves these markers on its own.
What hematocrit level is dangerous on testosterone therapy? Most clinicians treat 54% as the threshold requiring dose reduction or phlebotomy. Levels should be rechecked at 90 days and then periodically throughout 2026 treatment, since this is the marker most tied to clotting risk.
How often should blood pressure be checked during testosterone therapy? Monthly for the first three months, then quarterly if stable. A rise of more than 10 points from baseline warrants a dose or delivery method change before adding blood pressure medication.
Can testosterone therapy improve cholesterol? Some men see improved lipid panels as insulin sensitivity improves and fat mass drops, but the response isn't universal. Lipids should be rechecked at the 6-month mark regardless of symptom improvement.
Is testosterone therapy safe for men over 60? The TRAVERSE trial specifically included men aged 45 to 80 with existing cardiovascular risk factors and found no increased cardiac event rate in this population. Age alone isn't a disqualifier, but baseline cardiovascular risk needs documentation before starting.
How long before testosterone therapy shows cardiovascular-relevant changes? Hematocrit shifts appear within 90 days; lipid and blood pressure changes are usually evident by the 6-month mark. Full metabolic response typically takes 6 to 12 months to stabilize.
Should men with existing heart disease avoid testosterone therapy? Men with a recent cardiac event or unstable heart disease need cardiology clearance before starting, since TRAVERSE excluded men with recent unstable cardiovascular events. Stable, well-managed heart disease isn't an automatic disqualifier but does require closer monitoring.
One last thing
The detail most men miss: the original 2013-2014 warning studies that shaped a decade of physician caution never actually measured testosterone levels in half their subjects before treating them. TRAVERSE, by contrast, confirmed hypogonadism with two morning draws in every participant — which is exactly the standard your own clinician should hold you to before writing a prescription in 2026.
Related guides
- Hormone optimization for men over 50
- Best testosterone therapy options for men in 2026
- Low testosterone symptoms in men: what labs actually show
- GLP-1 and cardiovascular risk: what the studies show
- Medical weight loss for men with metabolic syndrome
References
- Testosterone Therapy in Men with Hypogonadism: An Endocrine Society Clinical Practice Guideline. 2018. doi.org/10.1210/jc.2018-00229