J Clin Endocrinol Metab 2000 Aug;85(8):2839-53
improves sexual function, mood, muscle strength,
and body composition parameters
in hypogonadal men.
Testosterone Gel Study Group.
Wang C, Swedloff RS, Iranmanesh A, Dobs A, Snyder PJ,
Matsumoto AM, Weber T, Berman N
Department of Medicine, Harbor-University of California-Los Angeles Medical
and Research and Education Institute, Torrance 90509, USA.
Testosterone (T) therapy for hypogonadal men should correct the clinical
abnormalities of T deficiency, including improvement of sexual function,
increase in muscle mass and strength, and decrease in fat mass, with minimal
adverse effects. We have shown that administration of a new transdermal
T gel formulation to hypogonadal men provided dose proportional increases
in serum T levels to the normal adult male range. We now report the effects
of 180 days of treatment with this 1% T gel preparation (50 or 100 mg/day,
contained in 5 or 10 g gel, respectively) compared to those of a permeation-enhanced
T patch (5 mg/day) on defined efficacy parameters in 227 hypogonadal men.
In the T gel groups, the T dose was adjusted up or down to 75 mg/day (contained
in 7.5 g gel) on day 90 if serum T concentrations were below or above
the normal male range. No dose adjustment was made with the T patch group.
Sexual function and mood changes were monitored by questionnaire, body
composition was determined by dual energy x-ray absorptiometry, and muscle
strength was measured by the one repetitive maximum technique on bench
and leg press exercises. Sexual function and mood improved maximally on
day 30 of treatment, without differences across groups, and showed no
further improvement with continuation of treatment. Mean muscle strength
in the leg press exercise increased by 11 to 13 kg in all treatment groups
by 90 days and did not improve further at 180 days of treatment. Moderate
increases were also observed in arm/chest muscle strength. At 90 days
of treatment, lean body mass increased more in the 100 mg/day T gel group
(2.74 +/- 0.28 kg; P = 0.0002) than in the 50 mg/day T gel (1.28 +/- 0.32
kg) and T patch groups (1.20 +/- 0.26 kg). Fat mass and percent fat were
not significantly decreased in the T patch group, but showed decreases
in the T gel groups (50 mg/day, -0.90 +/- 0.32 kg; 100 mg/day, - 1.05
+/- 0.22 kg). The increase in lean mass and the decrease in fat mass were
correlated with the changes in average serum T levels attained after transdermal
T replacement. These beneficial effects of T replacement were accompanied
by the anticipated increases in hematocrit and hemoglobin but without
significant changes in the lipid profile. The increase in mean serum prostate-specific
antigen levels (within the normal range) was correlated with serum levels
of T. The greatest increases were noted in the 100 mg/day T gel group.
Skin irritation was reported in 5.5% of subjects treated with T gel and
in 66% of subjects in the permeation-enhanced T patch group. We conclude
that T gel replacement improved sexual function and mood, increased lean
mass and muscle strength (principally in the legs), and decreased fat
mass in hypogonadal men with less skin irritation and discontinuation
compared with the recommended dose of the permeation-enhanced T patch.