Siegmann Eva-Maria, Olm Pauline, Lenz Bernd, Mühle Christiane, Oberstein Timo Jan, Maler Juan Manuel, Kornhuber Johannes
Department of Psychiatry and Psychotherapy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Schwabachanlage 6, 91054 Erlangen, Germany.
Department of Addictive Behavior and Addiction Medicine, Central Institute of Mental Health (CIMH), Medical Faculty Mannheim, Heidelberg University, 68159 Mannheim, Germany.
Brain Sci. 2023 Aug 22;13(9):1229. doi: 10.3390/brainsci13091229.
The development of Alzheimer's disease (AD) is influenced by sex hormones-estrogens and androgens in particular. However, the impact of prenatal sex hormone exposure is less clear; very few investigations have examined the relationship between the second-to-fourth digit length ratio (2D:4D), a putative proxy for the ratio of prenatal estrogens to androgens, and AD, with inconsistent results among the few that have. Therefore, we aimed to investigate this relationship using methodologically robust metrics. In a 2 (sex) × 4 (group) MANOVA incorporating 108 participants (30 AD patients, 19 patients with tauopathy but no amyloidopathy, 31 clinical and 28 healthy age- and education-matched controls), the effects of sex and group on the dependent variables right and left 2D:4D were examined. We also explored the association between 2D:4D and the severity of AD symptoms assessed via neuropsychological examination. We did not find any significant differences in the right- and left-hand 2D:4D between patients with AD and the other groups; no significant associations between 2D:4D and neuropsychological task performances were found in the dementia groups. The 2D:4D of healthy women was significantly lower than that of depressed women without AD, i.e., clinical controls, but not significantly different from depressed female patients with AD. This investigation does not support the role of 2D:4D in the development or severity of AD in general, but suggests a potential role of 2D:4D for depression in women. Future studies are warranted to clarify whether 2D:4D can distinguish between early- and late-onset depression in women.
阿尔茨海默病（AD）的发展受到性激素，尤其是雌激素和雄激素的影响。然而，产前性激素暴露的影响尚不清楚；很少有研究探讨第二至第四指长度比（2D:4D）（一种假定的产前雌激素与雄激素比例的替代指标）与AD之间的关系，少数相关研究的结果并不一致。因此，我们旨在使用方法上可靠的指标来研究这种关系。在一项纳入108名参与者（30名AD患者、19名患有tau蛋白病但无淀粉样蛋白病的患者、31名临床对照者以及28名年龄和教育程度匹配的健康对照者）的2（性别）×4（组）多变量方差分析（MANOVA）中，研究了性别和组对因变量右手和左手2D:4D的影响。我们还探讨了2D:4D与通过神经心理学检查评估的AD症状严重程度之间的关联。我们发现AD患者与其他组之间在右手和左手的2D:4D上没有任何显著差异；在痴呆组中未发现2D:4D与神经心理学任务表现之间存在显著关联。健康女性的2D:4D显著低于无AD的抑郁女性，即临床对照者，但与患有AD的抑郁女性患者没有显著差异。这项研究总体上不支持2D:4D在AD发展或严重程度中的作用，但表明2D:4D对女性抑郁症可能有潜在作用。有必要进行进一步研究以阐明2D:4D是否能区分女性早发性和晚发性抑郁症。
