Clinical and Laboratory Characteristics of Fatigue-Dominant Long-COVID Subjects: A Cross-Sectional Study

IF 2.5 3区医学 Q1 MEDICINE, GENERAL & INTERNAL

American Journal of Medicine Pub Date : 2025-02-01 DOI:10.1016/j.amjmed.2024.01.025

Jin-Seok Lee PhD , Yujin Choi MD , Jin-Yong Joung MD, PhD , Chang-Gue Son MD, PhD

{"title":"Clinical and Laboratory Characteristics of Fatigue-Dominant Long-COVID Subjects: A Cross-Sectional Study","authors":"Jin-Seok Lee PhD , Yujin Choi MD , Jin-Yong Joung MD, PhD , Chang-Gue Son MD, PhD","doi":"10.1016/j.amjmed.2024.01.025","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div><span>Long COVID is defined by persistent symptoms following COVID-19 infection. Approximately 71% of individuals with long COVID experience ongoing fatigue, postexertional malaise, and </span>cognitive impairments, which share pathological similarities with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). This similarity has prompted studies to explore the characteristics of long COVID to gain a better understanding of ME/CFS. To gain insights, we investigated the clinical and laboratory characteristics of individuals with fatigue-dominant long COVID.</div></div><div><h3>Methods</h3><div><span>We enrolled 100 subjects (36 males, 64 females) with long COVID who had a higher score than 60 in the modified Korean version of the Chalder Fatigue Scale (mKCFQ11) and higher than 5 in a fatigue-focused visual analogue scale. To investigate fatigue symptoms, the mKCFQ11, the Multidimensional Fatigue Inventory, a visual analogue scale for fatigue and brain fog, along with the Short-Form survey, were employed. We also measured 3 cytokines and </span>cortisol levels for immunological and endocrinological indicators. As a cross-sectional observational study, the data were collected at a single point in time.</div></div><div><h3>Results</h3><div>The mean scores on the measurements showed severe fatigue, and these scores were significantly correlated, with no differences based on sex, the post-COVID period, or age. Among the laboratory tests<span>, plasma cortisol<span><span> levels had a significant negative correlation with fatigue scores and a positive correlation with living quality. The negative correlation between cortisol levels and mKCFQ11 scores appeared to be more specific to </span>mental fatigue than physical, which conflicted with other measurements.</span></span></div></div><div><h3>Conclusion</h3><div>Our findings provide the first insights into the characteristics of fatigue in individuals with long COVID, particularly in terms of fatigue severity and cortisol levels. These results serve as valuable reference data for clinicians dealing with fatigue symptoms in long-COVID patients and for researchers exploring postviral fatigue symptoms, including ME/CFS, in the future.</div></div>","PeriodicalId":50807,"journal":{"name":"American Journal of Medicine","volume":"138 2","pages":"Pages 346-353.e1"},"PeriodicalIF":2.5000,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"American Journal of Medicine","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0002934324000573","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MEDICINE, GENERAL & INTERNAL","Score":null,"Total":0}

引用次数: 0

Abstract

Background

Long COVID is defined by persistent symptoms following COVID-19 infection. Approximately 71% of individuals with long COVID experience ongoing fatigue, postexertional malaise, and cognitive impairments, which share pathological similarities with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). This similarity has prompted studies to explore the characteristics of long COVID to gain a better understanding of ME/CFS. To gain insights, we investigated the clinical and laboratory characteristics of individuals with fatigue-dominant long COVID.

Methods

We enrolled 100 subjects (36 males, 64 females) with long COVID who had a higher score than 60 in the modified Korean version of the Chalder Fatigue Scale (mKCFQ11) and higher than 5 in a fatigue-focused visual analogue scale. To investigate fatigue symptoms, the mKCFQ11, the Multidimensional Fatigue Inventory, a visual analogue scale for fatigue and brain fog, along with the Short-Form survey, were employed. We also measured 3 cytokines and cortisol levels for immunological and endocrinological indicators. As a cross-sectional observational study, the data were collected at a single point in time.

Results

The mean scores on the measurements showed severe fatigue, and these scores were significantly correlated, with no differences based on sex, the post-COVID period, or age. Among the laboratory tests, plasma cortisol levels had a significant negative correlation with fatigue scores and a positive correlation with living quality. The negative correlation between cortisol levels and mKCFQ11 scores appeared to be more specific to mental fatigue than physical, which conflicted with other measurements.

Conclusion

Our findings provide the first insights into the characteristics of fatigue in individuals with long COVID, particularly in terms of fatigue severity and cortisol levels. These results serve as valuable reference data for clinicians dealing with fatigue symptoms in long-COVID patients and for researchers exploring postviral fatigue symptoms, including ME/CFS, in the future.

查看原文本刊更多论文

以疲劳为主的长期 COVID 患者的临床和实验室特征：一项横断面研究

背景：长COVID是指感染COVID-19后出现的持续症状。约 71% 的长期 COVID 患者会出现持续疲劳、劳累后乏力和认知障碍，其病理特征与肌痛性脑脊髓炎/慢性疲劳综合征（ME/CFS）相似。这种相似性促使研究人员探索长COVID的特征，以便更好地理解ME/CFS。为了加深理解，我们调查了以疲劳为主的长COVID患者的临床和实验室特征：我们招募了 100 名患有长COVID的受试者（36 名男性，64 名女性），这些受试者的改良版韩国查尔德疲劳量表（mKCFQ11）得分高于 60 分，以疲劳为重点的视觉模拟量表（VAS）得分高于 5 分。为了调查疲劳症状，我们采用了 mKCFQ11、多维疲劳量表 (MFI-20)、疲劳和脑雾 VAS 以及短表调查 (SF-12)。我们还测量了三种细胞因子和皮质醇水平，以了解免疫学和内分泌学指标。作为一项横断面观察研究，数据是在一个时间点收集的：结果：测量结果的平均分显示出严重的疲劳感，而且这些分数与性别、COVID 后时期或年龄无显著相关性。在实验室检测中，血浆皮质醇水平与疲劳评分呈显著负相关，与生活质量呈正相关。皮质醇水平与 mKCFQ11 分数之间的负相关似乎更多的是针对精神疲劳，而不是身体疲劳，这与其他测量结果相矛盾：我们的研究结果首次揭示了长期 COVID 患者的疲劳特征，尤其是疲劳严重程度和皮质醇水平。这些结果为临床医生处理长期 COVID 患者的疲劳症状提供了宝贵的参考数据，也为研究人员今后探索病毒后疲劳症状（包括 ME/CFS ）提供了宝贵的参考数据。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

American Journal of Medicine 医学-医学：内科

CiteScore

6.30

自引率

3.40%

发文量

449

审稿时长

9 days

期刊介绍： The American Journal of Medicine - "The Green Journal" - publishes original clinical research of interest to physicians in internal medicine, both in academia and community-based practice. AJM is the official journal of the Alliance for Academic Internal Medicine, a prestigious group comprising internal medicine department chairs at more than 125 medical schools across the U.S. Each issue carries useful reviews as well as seminal articles of immediate interest to the practicing physician, including peer-reviewed, original scientific studies that have direct clinical significance and position papers on health care issues, medical education, and public policy.