TREATMENT WITH OXANDROLONE AND THE DURABILITY OF EFFECTS IN OLDER MEN

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。我们研究了合成代谢雄激素氧雄龙对瘦体重（LBM），肌肉大小，脂肪和最大随意肌肉力量的影响，并确定了治疗停止后效果的持久性。32名60- 87岁的健康男性随机接受20 mg氧雄龙/天（n = 20）或安慰剂（n = 12）12周。在基线和治疗12周后评价身体成分[双能X线吸收测定法（DEXA）、磁共振成像和2 H2O稀释]和肌肉力量[最多重复1次（1 RM）];然后在治疗停止后12周（第24周）评估身体成分（DEXA）和1-RM力量。第12周，氧甲氢龙使LBM增加3.0 ± 1.5 kg（P < 0.001），体内总水量增加2.9 ± 3.7 kg（P = 0.002），大腿近端肌肉面积增加12.4 ± 8.4 cm 2（P < 0.001）;这些增加幅度（P < 0.003）大于安慰剂组。氧甲氢龙使1-RM力量增加6.7 <$6.4%（P < 0.001），腿部屈曲7.0 <$7.8%（P < 0.001），胸部按压9.3 <$6.7%（P < 0.001），阔肌下拉运动5.1 <$9.1%（P = 0.02）;这些增加大于安慰剂。氧甲氢龙减少总脂肪（-1.9 <$1.0 kg）和躯干脂肪（-1.3 <$0.6 kg; P < 0.001），这些减少幅度大于安慰剂（P < 0.001）。停用氧雄龙12周后（第24周），LBM和肌肉力量的增量与基线相比不再有差异（P > 0.15）。然而，总脂肪和躯干脂肪的减少持续（分别为-1.5 <$1.8，P = 0.001和-1.0 <$1.1 kg，P < 0.001）。因此，氧雄龙诱导LBM，肌肉面积和强度的短期改善，同时减少全身和躯干肥胖。合成代谢的改善在停用氧雄龙后12周丢失，而脂肪量的改善在很大程度上是持续的。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We investigated the effects of the anabolic androgen, oxandrolone, on lean body mass (LBM), muscle size, fat, and maximum voluntary muscle strength, and we determined the durability of effects after treatment was stopped. Thirty-two healthy 60- to 87-yr-old men were randomized to receive 20 mg oxandrolone/day (n = 20) or placebo (n = 12) for 12 wk. Body composition [dual-energy X-ray absorptiometry (DEXA), magnetic resonance imaging, and 2H2O dilution] and muscle strength [1 repetition maximum (1 RM)] were evaluated at baseline and after 12 wk of treatment; body composition (DEXA) and 1-RM strength were then assessed 12 wk after treatment was discontinued (week 24). At week 12, oxandrolone increased LBM by 3.0 ¿ 1.5 kg (P < 0.001), total body water by 2.9 ¿ 3.7 kg (P = 0.002), and proximal thigh muscle area by 12.4 ¿ 8.4 cm2 (P < 0.001); these increases were greater (P < 0.003) than in the placebo group. Oxandrolone increased 1-RM strength for leg press by 6.7 ¿ 6.4% (P < 0.001), leg flexion by 7.0 ¿ 7.8% (P < 0.001), chest press by 9.3 ¿ 6.7% (P < 0.001), and latissimus pull-down exercises by 5.1 ¿ 9.1% (P = 0.02); these increases were greater than placebo. Oxandrolone reduced total (-1.9 ¿ 1.0 kg) and trunk fat (-1.3 ¿ 0.6 kg; P < 0.001), and these decreases were greater (P < 0.001) than placebo. Twelve weeks after oxandrolone was discontinued (week 24), the increments in LBM and muscle strength were no longer different from baseline (P > 0.15). However, the decreases in total and trunk fat were sustained (-1.5 ¿ 1.8, P = 0.001 and -1.0 ¿ 1.1 kg, P < 0.001, respectively). Thus oxandrolone induced short-term improvements in LBM, muscle area, and strength, while reducing whole body and trunk adiposity. Anabolic improvements were lost 12 wk after discontinuing oxandrolone, whereas improvements in fat mass were largely sustained.