BACKGROUND There is ongoing debate regarding the association between telogen effluvium (TE) and COVID-19, as well as COVID-19 vaccines. OBJECTIVES To investigate the impact of the COVID-19 pandemic and vaccination on the development of TE among patients visiting dermatology clinics in South Korea. METHODS Between 2017 and 2022, data regarding patients with TE and other types of hair loss were collected from 22 hospitals in South Korea. An interrupted time series analysis was conducted, dividing the time into periods before and after the COVID-19 pandemic, as well as before and after the COVID-19 vaccination. RESULTS There was a significant slope change in the percentage of cases of TE during the postpandemic period (slope change 0.011, 95% confidence interval 0.005-0.017, P < 0.001), but no significant changes were observed after vaccination. The percentage of patients with other types of hair loss was not associated with COVID-19 or vaccination. The retrospective nature of the study may have limited the ability to establish causation. CONCLUSIONS This multicentre study provides insights into the epidemiology of TE, showing a significant increase in cases of TE following the COVID-19 pandemic. However, there was no association between the occurrence of TE and COVID-19 vaccines.

中文翻译：

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COVID-19 大流行对休止期脱发的影响：一项全国性多中心中断时间序列研究。


背景 关于休止期脱发 (TE) 与 COVID-19 以及 COVID-19 疫苗之间的关联一直存在争论。目的 调查 COVID-19 大流行和疫苗接种对韩国皮肤科诊所患者发生 TE 的影响。方法 2017 年至 2022 年间，从韩国 22 家医院收集了 TE 和其他类型脱发患者的数据。进行了中断时间序列分析，将时间分为 COVID-19 大流行之前和之后以及 COVID-19 疫苗接种之前和之后的时期。结果 大流行后时期 TE 病例百分比出现显着斜率变化（斜率变化 0.011，95% 置信区间 0.005-0.017，P< 0.001），但接种疫苗后未观察到显着变化。其他类型脱发患者的百分比与 COVID-19 或疫苗接种无关。该研究的回顾性可能限制了确定因果关系的能力。结论 这项多中心研究提供了对 TE 流行病学的深入了解，显示在 COVID-19 大流行后 TE 病例显着增加。然而，TE 的发生与 COVID-19 疫苗之间没有关联。