Abstract: Journal of the Chinese Medical Association Publish Ahead of Print
DOI: 10.1097/JCMA.0000000000001294
Association between vitamin D and COVID-19 infection and mortality in
ED
Taiwanese patients
Ching-Ching Shenga,b, Shuan-Yi Sua, Ying Lianga, Hui-Chuan Chenga, Hsin-Yi
Huangc,*, Hsiao-Hui Chiua,d,e,*
Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
b
Department of Nursing, Chang Jung Christian University, Tainan, Taiwan, ROC
EP
T
a
c
Department of Information Management, Taipei Veterans General Hospital, Taipei, Taiwan,
ROC
d
Department of Nursing, National Taipei University of Nursing and Health Sciences,
Taipei, Taiwan, ROC
e
School of Nursing, National Defense Medical Center, Taipei, Taiwan, ROC
C
Received date: September 24, 2024. Accepted date: August 22, 2025.
Author contributions: Rn Ching-Ching Sheng and Rn Shuan-Yi Su contributed equally to this
A
C
manuscript.
Conflicts of interest: The authors declare that they have no conflicts of interest related to the
subject matter or materials discussed in this article.
*Address correspondence. Rn. Hsiao-Hui Chiu, Department of Nursing, Taipei
Veterans General Hospital, 201, Section 2, Shi-Pai Road, Taipei 112 ,Taiwan, ROC.
Tel: +886-2871-12121 ext. 82398 Fax: +886-2875-7664 E-mail:
shchiu2@vghtpe.gov.tw
1
Ms. Hsin-Yi Huang, Department of Information Management, Taipei Veterans
General Hospital, 201, Section 2, Shi-Pai Road, Taipei 112, Taiwan, ROC. E-mail:
hyhuang21@vghtpe.gov.tw
Ching-Ching Sheng
ED
ORCID: 0009-0004-9324-0448
Shuan-Yi Su
ORCID: 0009-0009-6729-6989
Hsin-Yi Huang
Hsiao-Hui Chiu
EP
T
ORCID: 0000-0001-5073-3323
ORCID: 0000-0002-4889-3982
This is an open access article under the CC BY-NC-ND license
A
C
C
(http://creativecommons.org/licenses/by-nc-nd/4.0/).
2
Abstract
Background: Vitamin D plays a role in immune regulation and may influence COVID-19
outcomes. This study examined the association between serum vitamin D levels with COVID-19
infection and mortality in symptomatic patients in Taiwan.
ED
Methods: This retrospective cohort study included symptomatic patients who underwent
COVID-19 real-time polymerase chain reaction (RT-PCR) assay between 2020 and 2023. Serum
25-hydroxyvitamin D (25(OH)D) levels were categorized as deficient (<20 ng/mL), insufficient
(20–30 ng/mL), or sufficient (≥30 ng/mL). Logistic regression models were used to evaluate the
EP
T
impact of vitamin D levels on COVID-19 infection and mortality, adjusting for potential
confounders including age, sex, and comorbidities.
Results: Among the 481 participants (mean age 58.2 years; 66.7% female), 96 (19.96%) tested
positive for COVID-19. Vitamin D level was not associated with COVID-19 infection
(OR=1.00, 95% CI: 0.99–1.02, p=0.687), however vitamin D deficiency significantly increased
the risk of COVID-19-related mortality (OR=10.68, 95% CI: 1.18–96.45; p=0.035). The
C
mortality rate in patients aged 65–74 years was higher compared to those aged 19–44 years
(OR=12.91, 95% CI: 1.29–128.83; p=0.029).
A
C
Conclusions: Vitamin D levels were not associated with susceptibility to COVID-19 infection.
However, vitamin D deficiency, particularly in older patients, was associated with an increased
risk of mortality among those diagnosed with COVID-19. These findings support the role of
vitamin D in reducing COVID-19 mortality, and emphasize the importance of maintaining
sufficient levels in high-risk populations.
Keywords: COVID-19 infection;..
DOI record:
{
"DOI": "10.1097/jcma.0000000000001294",
"ISSN": [
"1726-4901"
],
"URL": "http://dx.doi.org/10.1097/JCMA.0000000000001294",
"abstract": "<jats:sec>\n <jats:title>Background:</jats:title>\n <jats:p>Vitamin D plays a role in immune regulation and may influence COVID-19 outcomes. This study examined the association between serum vitamin D levels with COVID-19 infection and mortality in symptomatic patients in Taiwan.</jats:p>\n </jats:sec>\n <jats:sec>\n <jats:title>Methods:</jats:title>\n <jats:p>This retrospective cohort study included symptomatic patients who underwent COVID-19 real-time polymerase chain reaction (RT-PCR) assay between 2020 and 2023. Serum 25-hydroxyvitamin D (25(OH)D) levels were categorized as deficient (<20 ng/mL), insufficient (20–30 ng/mL), or sufficient (≥30 ng/mL). Logistic regression models were used to evaluate the impact of vitamin D levels on COVID-19 infection and mortality, adjusting for potential confounders including age, sex, and comorbidities.</jats:p>\n </jats:sec>\n <jats:sec>\n <jats:title>Results:</jats:title>\n <jats:p>Among the 481 participants (mean age 58.2 years; 66.7% female), 96 (19.96%) tested positive for COVID-19. Vitamin D level was not associated with COVID-19 infection (OR=1.00, 95% CI: 0.99–1.02, <jats:italic toggle=\"yes\">p</jats:italic>=0.687), however vitamin D deficiency significantly increased the risk of COVID-19-related mortality (OR=10.68, 95% CI: 1.18–96.45; <jats:italic toggle=\"yes\">p</jats:italic>=0.035). The mortality rate in patients aged 65–74 years was higher compared to those aged 19–44 years (OR=12.91, 95% CI: 1.29–128.83; <jats:italic toggle=\"yes\">p</jats:italic>=0.029).</jats:p>\n </jats:sec>\n <jats:sec>\n <jats:title>Conclusions:</jats:title>\n <jats:p>Vitamin D levels were not associated with susceptibility to COVID-19 infection. However, vitamin D deficiency, particularly in older patients, was associated with an increased risk of mortality among those diagnosed with COVID-19. These findings support the role of vitamin D in reducing COVID-19 mortality, and emphasize the importance of maintaining sufficient levels in high-risk populations.</jats:p>\n </jats:sec>",
"author": [
{
"affiliation": [
{
"name": "Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
},
{
"name": "Department of Nursing, Chang Jung Christian University, Tainan, Taiwan, ROC"
}
],
"family": "Sheng",
"given": "Ching-Ching",
"sequence": "first"
},
{
"affiliation": [
{
"name": "Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
}
],
"family": "Su",
"given": "Shuan-Yi",
"sequence": "additional"
},
{
"affiliation": [
{
"name": "Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
}
],
"family": "Liang",
"given": "Ying",
"sequence": "additional"
},
{
"affiliation": [
{
"name": "Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
}
],
"family": "Cheng",
"given": "Hui-Chuan",
"sequence": "additional"
},
{
"affiliation": [
{
"name": "Department of Information Management, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
}
],
"family": "Huang",
"given": "Hsin-Yi",
"sequence": "additional"
},
{
"affiliation": [
{
"name": "Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan, ROC"
},
{
"name": "Department of Nursing, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan, ROC"
},
{
"name": "School of Nursing, National Defense Medical Center, Taipei, Taiwan, ROC"
}
],
"family": "Chiu",
"given": "Hsiao-Hui",
"sequence": "additional"
}
],
"container-title": "Journal of the Chinese Medical Association",
"content-domain": {
"crossmark-restriction": true,
"domain": [
"lww.com",
"ovid.com"
]
},
"created": {
"date-parts": [
[
2025,
9,
12
]
],
"date-time": "2025-09-12T11:01:19Z",
"timestamp": 1757674879000
},
"deposited": {
"date-parts": [
[
2025,
9,
12
]
],
"date-time": "2025-09-12T11:01:20Z",
"timestamp": 1757674880000
},
"indexed": {
"date-parts": [
[
2025,
9,
12
]
],
"date-time": "2025-09-12T15:44:09Z",
"timestamp": 1757691849531,
"version": "3.44.0"
},
"is-referenced-by-count": 0,
"issued": {
"date-parts": [
[
2025,
9,
12
]
]
},
"language": "en",
"link": [
{
"URL": "https://journals.lww.com/10.1097/JCMA.0000000000001294",
"content-type": "unspecified",
"content-version": "vor",
"intended-application": "similarity-checking"
}
],
"member": "276",
"original-title": [],
"prefix": "10.1097",
"published": {
"date-parts": [
[
2025,
9,
12
]
]
},
"published-online": {
"date-parts": [
[
2025,
9,
12
]
]
},
"publisher": "Ovid Technologies (Wolters Kluwer Health)",
"reference-count": 0,
"references-count": 0,
"relation": {},
"resource": {
"primary": {
"URL": "https://journals.lww.com/10.1097/JCMA.0000000000001294"
}
},
"score": 1,
"short-title": [],
"source": "Crossref",
"subject": [],
"subtitle": [],
"title": "Association between vitamin D and COVID-19 infection and mortality in Taiwanese patients",
"type": "journal-article",
"update-policy": "https://doi.org/10.1097/lww.0000000000001000"
}
