Fallah Nader, Mohammad Kazem, Nourijelyani Keramat, Eshraghian Mohammad Reza, Seyyedsalehi Seyyed Ali, Raiessi Maria, Rahmani Maziar, Goodarzi Hamid Reza, Darvish Soodabeh, Zeraati Hojjat, Davoodi Gholamreza, Sadeghian Saeed
Department of Epidemiology and Biostatistics, University of Tehran/Medical Sciences, Tehran, Iran.
Eur J Epidemiol. 2009;24(6):297-306. doi: 10.1007/s10654-009-9336-9. Epub 2009 Apr 9.
Previous studies have shown controversial results about the role of androgens in coronary artery disease (CAD). We performed this study to examine and compare the relationship between androgenic hormones and CAD using conventional linear statistical techniques as well as novel non-linear approaches. The study was conducted on 502 consecutive men who were referred for selective coronary angiography at Tehran Heart Center due to different indications. We studied the relationship between androgenic hormones and CAD by using the generalized linear models, generalized additive models, and neural networks. Free testosterone (fT), total testosterone (tT) and dehydroepiandrosterone sulfate levels in patients with significant CAD versus normal individuals were 6.69 +/- 3.20 pg/ml, 16.60 +/- 6.66 nm/l, and 113.38 +/- 72.9 microg/dl versus 7.12 +/- 3.58 pg/ml, 15.82 +/- 7.26 nm/l, and 109.03 +/- 68.19 microg/dl, respectively (P > 0.05). The Generalized linear models was unable to show any significant relationship between androgenic hormones and CAD, while generalized additive model and neural networks supported the significant effect of androgenic hormones on CAD. This finding suggests a nonlinear association of tT levels with CAD: lower levels have a preventive effect on CAD, whereas higher values increase the risk of CAD. Emphasizing the non-linearity of the variables may provide new insight into the possible explanation of the effect of androgenic hormones on CAD.
先前的研究对于雄激素在冠状动脉疾病（CAD）中的作用给出了相互矛盾的结果。我们开展这项研究，以使用传统线性统计技术以及新颖的非线性方法来检验和比较雄激素与CAD之间的关系。该研究针对502名因不同指征在德黑兰心脏中心接受选择性冠状动脉造影的连续男性患者进行。我们通过广义线性模型、广义相加模型和神经网络研究雄激素与CAD之间的关系。患有严重CAD的患者与正常个体相比，游离睾酮（fT）、总睾酮（tT）和硫酸脱氢表雄酮水平分别为6.69±3.20 pg/ml、16.60±6.66 nmol/l和113.38±72.9 μg/dl，而正常个体分别为7.12±3.58 pg/ml、15.82±7.26 nmol/l和109.03±68.19 μg/dl（P>0.05）。广义线性模型未能显示雄激素与CAD之间存在任何显著关系，而广义相加模型和神经网络支持雄激素对CAD有显著影响。这一发现表明tT水平与CAD之间存在非线性关联：较低水平对CAD有预防作用，而较高值会增加CAD风险。强调变量的非线性可能为解释雄激素对CAD的影响提供新的见解。
