AUTHOR=Li Ziqi , Hou Pengwei , Mu Shuwen , Wang Renzhi , Miao Hui , Feng Ming , Wang He , Zhang Wentai , Chen Yihao , Feng Tianshun , Wang Shousen , Fang Yi 

TITLE=Thyroxine changes in COVID-19 pandemic: A systematic review and meta-analysis

JOURNAL=Frontiers in Endocrinology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2023.1089190

DOI=10.3389/fendo.2023.1089190

ISSN=1664-2392

ABSTRACT=<sec><title>Objective</title><p>COVID-19 infection may affect thyroid function. However, changes in thyroid function in COVID-19 patients have not been well described. This systematic review and meta-analysis assess thyroxine levels in COVID-19 patients, compared with non-COVID-19 pneumonia and healthy cohorts during the COVID-19 epidemic.</p></sec><sec><title>Methods</title><p>A search was performed in English and Chinese databases from inception to August 1, 2022. The primary analysis assessed thyroid function in COVID-19 patients, comparing non-COVID-19 pneumonia and healthy cohorts. Secondary outcomes included different severity and prognoses of COVID-19 patients.</p></sec><sec><title>Results</title><p>A total of 5873 patients were enrolled in the study. The pooled estimates of TSH and FT3 were significantly lower in patients with COVID-19 and non-COVID-19 pneumonia than in the healthy cohort (P &lt; 0.001), whereas FT4 were significantly higher (P &lt; 0.001). Patients with the non-severe COVID-19 showed significant higher in TSH levels than the severe (I<sup>2</sup> = 89.9%, <italic>P</italic> = 0.002) and FT3 (I<sup>2</sup> = 91.9%, <italic>P</italic> &lt; 0.001). Standard mean differences (SMD) of TSH, FT3, and FT4 levels of survivors and non-survivors were 0.29 (<italic>P</italic>= 0.006), 1.11 (<italic>P</italic> &lt; 0.001), and 0.22 (<italic>P</italic> &lt; 0.001). For ICU patients, the survivors had significantly higher FT4 (SMD=0.47, <italic>P</italic>=0.003) and FT3 (SMD=0.51, P=0.001) than non-survivors.</p></sec><sec><title>Conclusions</title><p>Compared with the healthy cohort, COVID-19 patients showed decreased TSH and FT3 and increased FT4, similar to non-COVID-19 pneumonia. Thyroid function changes were related to the severity of COVID-19. Thyroxine levels have clinical significance for prognosis evaluation, especially FT3.</p></sec>