Geriatrics Division, Department of Medicine (DIMED), University of Padua, Padua, Italy.
Regional Reference Center for Gender Incongruence, Padua, Veneto Region, Italy.
J Endocrinol Invest. 2024 Feb;47(2):401-410. doi: 10.1007/s40618-023-02156-7. Epub 2023 Jul 14.
Preliminary data suggested that bone mineral density (BMD) in transgender adults before initiating gender-affirming hormone therapy (GAHT) is lower when compared to cisgender controls. In this study, we analyzed bone metabolism in a sample of transgender adults before GAHT, and its possible correlation with biochemical profile, body composition and lifestyle habits (i.e., tobacco smoke and physical activity).
Medical data, smoking habits, phospho-calcic and hormonal blood tests and densitometric parameters were collected in a sample of 125 transgender adults, 78 Assigned Females At Birth (AFAB) and 47 Assigned Males At Birth (AMAB) before GAHT initiation and 146 cisgender controls (57 females and 89 males) matched by sex assigned at birth and age. 55 transgender and 46 cisgender controls also underwent a complete body composition evaluation and assessment of physical activity using the International Physical Activity Questionnaire (IPAQ).
14.3% of transgender and 6.2% of cisgender sample, respectively, had z-score values < -2 (p = 0.04). We observed only lower vitamin D values in transgender sample regarding biochemical/hormonal profile. AFAB transgender people had more total fat mass, while AMAB transgender individuals had reduced total lean mass as compared to cisgender people (53.94 ± 7.74 vs 58.38 ± 6.91, p < 0.05). AFAB transgender adults were more likely to be active smokers and tend to spend more time indoor. Fat Mass Index (FMI) was correlated with lumbar and femur BMD both in transgender individuals, while no correlations were found between lean mass parameters and BMD in AMAB transgender people.
Body composition and lifestyle factors could contribute to low BMD in transgender adults before GAHT.
初步数据表明，在开始性别肯定激素治疗（GAHT）之前，跨性别成年人的骨密度（BMD）低于顺性别对照者。在这项研究中，我们分析了 GAHT 前跨性别成年人的骨代谢情况，及其与生化特征、身体成分和生活方式习惯（即，吸烟和体力活动）的可能相关性。
在 GAHT 开始前，我们收集了 125 名跨性别成年人、78 名出生时被指定为女性（AFAB）和 47 名出生时被指定为男性（AMAB）的医疗数据、吸烟习惯、磷钙和激素血液检查以及骨密度参数，同时还收集了 146 名出生时被指定性别和年龄匹配的顺性别对照者（57 名女性和 89 名男性）的数据。55 名跨性别者和 46 名顺性别对照者还接受了完整的身体成分评估和使用国际体力活动问卷（IPAQ）评估体力活动。
分别有 14.3%的跨性别者和 6.2%的顺性别者样本的 z 分数值 < -2（p = 0.04）。我们仅观察到跨性别者样本的生化/激素特征中维生素 D 值较低。AFAB 跨性别者的总脂肪量更多，而 AMAB 跨性别者的总瘦体重减少（53.94 ± 7.74 与 58.38 ± 6.91，p < 0.05）。AFAB 跨性别成年人更有可能是活跃的吸烟者，且更倾向于在室内度过更多时间。脂肪量指数（FMI）与跨性别者的腰椎和股骨 BMD 均相关，而 AMAB 跨性别者的瘦体重参数与 BMD 之间没有相关性。
在开始 GAHT 之前，身体成分和生活方式因素可能导致跨性别成年人的 BMD 降低。
