Table 4.
Longitudinal studies of muscle and strength changes in adult transgender women undergoing cross-sex hormone therapy
| Study | Participants (age) | Therapy | Confirmed serum testosterone levels | Muscle/strength data | Comparison with reference females |
|---|---|---|---|---|---|
| Polderman et al. [73] | N = 12 TW 18–36 yr (age range) | T suppression + E supplementation | < 2 nmol/L at 4 mo |
LBM 4 mo − 2.2% |
LBM 4 mo 16% |
| Gooren and Bunck [62] | N = 19 TW 26 ± 6 yr | T suppression + E supplementation | ≤ 1 nmol/L at 1 and 3 yr |
Thigh area 1 yr − 9% / 3 yr -12% |
Thigh area 1 yr 16%/3 yr 13% |
| Haraldsen et al. [63] | N = 12 TW 29 ± 8 yr | E supplementation | < 10 nmol/L at 3 mo and 1 yr |
LBM 3 mo/1 yr—small changes, unclear magnitude |
|
| Mueller et al. [64] | N = 84 TW 36 ± 11 yr | T suppression + E supplementation | ≤ 1 nmol/L at 1 and 2 yr |
LBM 1 yr − 4%/2 yr − 7% |
|
| Wierckx et al. [65] | N = 53 TW 31 ± 14 yr | T suppression + E supplementation | < 10 nmol/L at 1 yr |
LBM 1 yr − 5% |
LBM 1 yr 39% |
|
Van Caenegem et al. [53] (and Van Caenegem et al. [76]) |
N = 49 TW 33 ± 14 yr |
T suppression + E supplementation | ≤ 1 nmol/L at 1 and 2 yr |
LBM 1 yr − 4%/2 yr − 0.5% Grip strength 1 yr − 7%/2 yr − 9% Calf area 1 yr − 2%/2 yr − 4% Forearm area 1 yr − 8%/2 yr − 4% |
LBM 1 yr 24%/2 yr 28% Grip strength 1 yr 26%/2 yr 23% Calf area 1 yr 16%/2 yr 13% Forearm area 1 yr 29%/2 yr 34% |
| Gava et al. [66] |
N = 40 TW 31 ± 10 yr |
T suppression + E supplementation | < 5 nmol/L at 6 mo and ≤ 1 nmol/L at 1 yr |
LBM 1 yr − 2% |
|
| Auer et al. [67] |
N = 45 TW 35 ± 1 (SE) yr |
T suppression + E supplementation | < 5 nmol/L at 1 yr |
LBM 1 yr − 3% |
LBM 1 yr 27% |
| Klaver et al. [68] |
N = 179 TW 29 (range 18–66) |
T suppression + E supplementation | ≤ 1 nmol/L at 1 yr |
LBM 1 yr Total − 3% Arm region − 6% Trunk region − 2% Android region 0% Gynoid region − 3% Leg region − 4% |
LBM 1 yr Total 18% Arm region 28% Leg region 19% |
| Fighera et al. [69] |
N = 46 TW 34 ± 10 |
E supplementation with or without T suppression |
< 5 nmol/L at 3 mo ≤ 1 nmol/L at 31 mo |
ALM 31 mo − 4% from the 3 mo visit |
|
| Scharff et al. [70] |
N = 249 TW 28 (inter quartile range 23–40) |
T suppression + E supplementation | ≤ 1 nmol/L at 1 yr |
Grip strength 1 yr − 4% |
Grip strength 1 yr 21% |
| Wiik et al. [71] |
N = 11 TW 27 ± 4 |
T suppression + E supplementation | ≤ 1 nmol/L at 4 mo and at 1 yr |
Thigh volume 1 yr − 5% Quad area 1 yr − 4% Knee extension strength 1 yr 2% Knee flexion strength 1 yr 3% |
Thigh volume 1 yr 33% Quad area 26% Knee extension strength 41% Knee flexion strength 33% |
Studies reporting measures of lean mass, muscle volume, muscle area or strength are included. Muscle/strength data are calculated in reference to baseline cohort data and, where reported, reference female (or transgender men before treatment) cohort data. Tack et al. [72] was not included in the table since some of the participants had not completed full puberty at treatment initiation. van Caenegem et al. [76] reports reference female values measured in a separately-published, parallel cohort of transgender men
N number of participants, TW transgender women, Yr year, Mo month, T testosterone, E estrogen. ± Standard deviation (unless otherwise indicated in text), LBM lean body mass, ALM appendicular lean mass