Use of testosterone therapy, marketed to consumers for a condition
vaguely labeled as “low T,” is increasingly common; , in a
short-term randomized trial published in 2010, the incidence of
adverse cardiovascular events was higher in older men with
comorbidities who received testosterone therapy (NEJM JW Gen Med Jul
15 2010).  In the past year, two studies shed light on those
concerns.

In one retrospective study, researchers identified 8700 male veterans
with, or at high risk for heart disease whose blood testosterone
levels had been measured and were <300 ng/dL; 1200 of these men
received testosterone therapy, and 7500 did not. During a mean 27-
month follow-up, myocardial infarction, stroke, or death occurred in
26% of testosterone patients and in 20% of those not receiving
therapy. Higher risk for adverse events with testosterone therapy
occurred regardless of the presence or absence of heart disease.(NEJM JW

Gen Med Nov 19 2013).

Very little is known about risks associated with testosterone
therapy, but that fact doesn’t seem to be inhibiting its vigorous
promotion by pharmaceutical companies. For now, clinicians are
confronted regularly with the need to balance demands of men who seek
to improve their strength, energy, and appearance with theoretical
(and now, empirical) concerns about long-term risks of testosterone
therapy.

In another study, 140 men (age, 40–70) with erectile dysfunction and
low testosterone levels received optimized sildenafil (Viagra) therapy and then
were randomized to add daily transdermal testosterone (5–15 g) or
placebo for 14 weeks. Erectile function improved with sildenafil, but
add-on testosterone led to no further improvement (NEJM JW Gen Med Jan
2 2013).