University of Michigan Medical School, Ann Arbor, MI.
Department of Physical Medicine and Rehabilitation, Harvard Medical School/Spaulding Rehabilitation Hospital, Boston, MA.
Med Sci Sports Exerc. 2021 Sep 1;53(9):1969-1974. doi: 10.1249/MSS.0000000000002660.
The Female Athlete Triad (Triad) is common in female athletes. The Triad is caused by low-energy availability (EA), which is often difficult to measure and has been postulated to be associated with low-iron status. Here, we explore whether markers of low-iron status may be associated with indicators of low EA including Triad risk factors.
A total of 239 female National Collegiate Athletic Association Division I athletes completed preparticipation examinations that included Triad risk factors, medication/supplement use, diagnosis of anemia, and elected to complete dual-energy x-ray absorptiometry scan to measure bone mineral density. The association of markers of low iron (defined as self-report of iron supplementation and/or history of anemia) with each component of the Triad risk assessment score was assessed by stratifying low-iron status across different levels of Triad risk category. Differences across iron status groups were assessed using Fisher exact testing.
Every component of the Triad risk assessment score excluding delayed menarche was associated with low-iron status. The proportion of women who reported low iron was 11.5% in the low-risk EA group compared with 50% in the moderate-risk and 66.7% in the high-risk EA groups (P = 0.02); respectively. These numbers were 11.6%, 25.0%, and 66.7% (P = 0.02) for body mass index; 9.7%, 16.7%, and 25.0% (P < 0.05) for oligomenorrhea; 10.3%, 45.5%, and 50.0% (P < 0.01) for bone mineral density; and 10.4%, 20.8%, and 30.8% (P = 0.03) for history of stress reaction or fracture. Lean/endurance athletes were more likely to have low-iron status than other athletes (15.5% vs 3.4%, P = 0.02).
Markers for low-iron status were associated with Triad risk factors. Our study suggests that female athletes with a history of anemia or iron supplementation may require further screening for low EA.
女性运动员三联征(三联征)在女性运动员中很常见。三联征是由能量供应不足(EA)引起的,这通常很难测量,并被推测与低铁状态有关。在这里,我们探讨低铁状态的标志物是否与低 EA 的指标相关,包括三联征的危险因素。
共有 239 名美国大学生体育协会一级联赛的女性运动员完成了参赛前检查,其中包括三联征的危险因素、药物/补品的使用、贫血的诊断以及选择完成双能 X 射线吸收法扫描以测量骨矿物质密度。通过将低铁状态分层到不同的三联征风险类别水平,评估低铁状态与三联征风险评估评分的每个组成部分之间的关联。使用 Fisher 精确检验评估铁状态组之间的差异。
除了月经初潮延迟外,三联征风险评估评分的每个组成部分都与低铁状态有关。在低 EA 风险组中,报告低铁的女性比例为 11.5%,而在中风险组和高风险组中分别为 50%和 66.7%(P=0.02)。这些数字在体重指数方面分别为 11.6%、25.0%和 66.7%(P=0.02);分别为 9.7%、16.7%和 25.0%(P<0.05);分别为 10.3%、45.5%和 50.0%(P<0.01);分别为 10.4%、20.8%和 30.8%(P=0.03);在骨矿物质密度方面,分别为 10.3%、45.5%和 50.0%(P<0.01);在应激反应或骨折史方面,分别为 10.4%、20.8%和 30.8%(P=0.03)。瘦/耐力运动员比其他运动员更容易出现低铁状态(15.5%比 3.4%,P=0.02)。
低铁状态的标志物与三联征的危险因素相关。我们的研究表明,有贫血或铁补充史的女性运动员可能需要进一步筛查低 EA。