Supplementary Material for: Disease Severity Is Associated with Alexithymia in Patients with Atopic Dermatitis

<b><i>Background:</i></b> Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is associated with higher rates of psychological disorders, but limited evidence supported the association with alexithymia, a psychoaffective dysfunction. <b><i>Objectives:</i></b> This study was aimed to investigate the occurrence of alexithymia in AD patients, compared to healthy subjects. <b><i>Methods:</i></b> This cross-sectional study assessed AD severity by the Eczema Area and Severity Index (EASI) score, sleeplessness and itch by a numeric rating scale (NRS), and alexithymia by the 20-item Toronto Alexithymia Scale (TAS-20) score. The association between disease characteristics and alexithymia was evaluated through several logistic regression models. <b><i>Results:</i></b> 202 AD patients and 240 healthy subjects were included in this study. The alexithymic personality trait (TAS-20 ≥51) was more frequently observed among AD patients compared to the control group (62.4% [126/202] vs. 29.2% [70/240], <i>p</i> &lt; 0.0001). In particular, alexithymia (TAS-20 score ≥61) was detected in a significantly higher number of AD patients than in the controls (27.7% [56/202] vs. 7.5% [18/240]; <i>p</i> &lt; 0.0001), whereas borderline alexithymia was detected in 34.6% (70/202) of AD patients compared to 21.7% of healthy controls. Alexithymia was more common among severe AD patients (43.6%) compared to mild AD patients (15.6%) and correlated with itch intensity and sleep disturbances. Among clinical variables, ordered logistic regression analyses revealed disease severity as predictor of alexithymia. Indeed, univariate analysis showed EASI score, sleep NRS, and itch NRS being significantly associated with alexithymia, while a multivariate model identified increased EASI score values as predicting factor. <b><i>Conclusion:</i></b>This study described alexithymia in AD patients correlating its occurrence with clinical AD severity markers (EASI score, itch, and sleeplessness) and identifying the increase in EASI score as predicting factor.

<b><i>背景：</i></b> 特应性皮炎（Atopic Dermatitis, AD）是一种慢性炎症性皮肤疾病，常伴随更高的心理疾病发病风险，但目前仅有有限证据支持其与述情障碍（alexithymia）——一种心理情感功能障碍——存在关联。
<b><i>研究目的：</i></b> 本研究旨在探讨特应性皮炎患者群体中述情障碍的发生情况，并与健康受试者进行对比。
<b><i>研究方法：</i></b> 本项横断面研究采用湿疹面积及严重度指数（Eczema Area and Severity Index, EASI）评分评估特应性皮炎的严重程度，通过数字评定量表（numeric rating scale, NRS）评估失眠与瘙痒症状，采用20条目多伦多述情障碍量表（20-item Toronto Alexithymia Scale, TAS-20）评分衡量述情障碍水平。通过多组逻辑回归模型，分析疾病特征与述情障碍之间的关联。
<b><i>研究结果：</i></b> 本研究共纳入202名特应性皮炎患者与240名健康受试者。与对照组相比，特应性皮炎患者中述情障碍人格特质（TAS-20评分≥51）的检出率显著更高（62.4% [126/202] vs. 29.2% [70/240]，<i>p</i> < 0.0001）。具体而言，重度述情障碍（TAS-20评分≥61）在特应性皮炎患者中的检出率同样显著高于对照组（27.7% [56/202] vs. 7.5% [18/240]；<i>p</i> < 0.0001），而边界型述情障碍的检出率在特应性皮炎患者中为34.6%（70/202），显著高于健康对照组的21.7%。述情障碍在重度特应性皮炎患者中的发生率（43.6%）高于轻度特应性皮炎患者（15.6%），且与瘙痒强度及睡眠障碍呈正相关。临床变量分析显示，有序逻辑回归分析结果表明疾病严重程度是述情障碍的预测因素。单因素分析结果显示，EASI评分、睡眠NRS评分及瘙痒NRS评分均与述情障碍存在显著关联；多因素模型则进一步证实，EASI评分升高是述情障碍的独立预测因子。
<b><i>研究结论：</i></b> 本研究明确了特应性皮炎患者群体中述情障碍的发生情况，证实其与特应性皮炎的临床严重程度标志物（EASI评分、瘙痒症状及睡眠障碍）存在关联，并确定EASI评分升高为述情障碍的预测因素。