Clinical characteristics, outcomes, and risk factors of SARS-CoV-2 breakthrough infections among 572 fully vaccinated (BBIBP-CorV) hospitalized patients

Yihuang Liu; Peilin Liu; Yuming Sun; Guangtong Deng

doi:10.1016/j.heliyon.2023.e21387

Clinical characteristics, outcomes, and risk factors of SARS-CoV-2 breakthrough infections among 572 fully vaccinated (BBIBP-CorV) hospitalized patients

Heliyon. 2023 Oct 21;9(11):e21387. doi: 10.1016/j.heliyon.2023.e21387. eCollection 2023 Nov.

Authors

Yihuang Liu^{1

2

3

4

5}, Peilin Liu⁶, Yuming Sun⁷, Guangtong Deng^{1

2

3

4

5}

Affiliations

¹ Department of Dermatology, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
² National Engineering Research Center of Personalized Diagnostic and Therapeutic Technology, Changsha, Hunan, 410008, China.
³ Furong Laboratory, Changsha, Hunan, 410008, China.
⁴ Hunan Key Laboratory of Skin Cancer and Psoriasis, Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
⁵ National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
⁶ Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, Hunan Province, 410008, China.
⁷ Department of Plastic and Cosmetic Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.

Abstract

Background: Breakthrough infections have been widely reported in vaccinated individuals. However, the clinical characteristics, outcomes, and risk factors of SARS-CoV-2 breakthrough infections among fully vaccinated (BBIBP-CorV) hospitalized patients have not yet been fully elucidated.

Methods: In the single-center cohort study conducted at Xiangya Hospital of Central South University, we enrolled the hospitalized COVID-19 patients who had received full (2 doses) vaccination with the BBIBP-CorV vaccine between December 5, 2022, and January 31, 2023. We collected and analyzed information related to clinical characteristics, laboratory results, treatments, outcomes and prognostic data. Univariate and multivariable Cox regression were performed to assess the impact of clinical characteristics and laboratory results on the composite outcome (including the initiation of endotracheal intubation, non-invasive respiratory support, intensive care unit admission, and all-cause death).

Results: A total of 572 COVID-19 hospitalized patients with fully vaccinated (BBIBP-CorV) were included. The median age of the patients was 66 years (IQR 53, 74). The most common symptoms included fever (347 [60.7 %]), dry cough (401 [70.1 %]), and expectoration (333 [58.2 %]). Among those with pre-existing chronic comorbidities, 44.2 % had hypertension and 20.5 % had diabetes. Laboratory tests revealed that the majority of patients (425/549 [77.4 %]) had normal white blood cell counts. Composite outcome occurred in 11.9 % of patients, with 96.7 % of patients discharged and 3.3 % of patients died. Multivariate Cox regression analyses suggested that the NLR >4 (adjusted HR, 5.50 [95%CI: 1.56-19.47]; P = 0.008), D-dimer >0.5 mg/ml (adjusted HR, 2.17 [95%CI: 1.03-4.59]; P = 0.042) and procalcitonin >0.1 ng/ml (adjusted HR, 3.22 [95%CI: 1.38-7.52]; P = 0.007) were independently associated with the composite outcome.

Conclusion: Breakthrough infection after being fully vaccinated (BBIBP-CorV) is more likely to occur in older patients and patients with pre-existing chronic comorbidities. NLR >4, D-dimer >0.5 mg/ml and procalcitonin >0.1 ng/ml were independent risk factors for composite outcome.

Keywords: BBIBP-CorV; Breakthrough infection; COVID-19; Clinical characteristics; Outcome; Prognosis.