Determination of factors associated with severity of COVID-19 patients in Naresuan University Hospital


  • Jidabha Jedpiyawongse Faculty of medicine, Naresuan University
  • Piyarat Lauvahutanon Faculty of Medicine, Naresuan University
  • Piyatida Saengon Faculty of Medicine, Naresuan University
  • Poonchoke Pongsanum Faculty of Medicine, Naresuan University
  • Thanatsada Khamchu Faculty of Medicine, Naresuan University
  • Sakchai Chaimahapreuk Faculty of Medicine, Naresuan University
  • Rawisut Deoisares Faculty of Medicine, Naresuan University
  • Thanyasiri Jindayok Faculty of Medicine, Naresuan University



COVID-19, risk factor, severity, progression


COVID-19 patients may have different disease progression depending on certain factors such as age and underlying medical conditions, which also affect the severity and progression of COVID-19. Our study objective is to study the relationship between SARS-CoV-2 cycle threshold (Ct) and other factors associated with the severity of COVID-19. The data were collected from a total of 196 COVID-19 patients aged >18 years, who were hospitalized between 1 August and 31 December 2021 at Naresuan University Hospital. Of the 196 patients, 54 (27.5%) were suffering from severe covid. Based on multivariate analysis, Ct of N gene (p-value=0.721) and Ct of ORF1ab gene (p-value=0.490) were not associated with severe illness. Nonetheless, risk factors contributing to severity and progression of COVID-19 are age >60 years (aOR=6.81 (2.79-16.62), p-value<0.001) and having any one of comorbidities, e.g. obesity, chronic kidney disease, chronic obstructive pulmonary disease (COPD), cardiovascular disease, cerebrovascular disease, uncontrolled diabetes, and cirrhosis (aOR=2.30 (1.03-5.11), p-value=0.042). The protective factor against severe covid is having received >2 doses of vaccination (aOR=0.22 (0.08-0.64), p-value=0.005). It is therefore important to closely monitor potential severe illness among the elderly population and those with underlying medical conditions, as well as encouraging these high-risk groups to receive at least two doses of vaccine to reduce the risk of severe COVID-19 infections.


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How to Cite

Jedpiyawongse J, Lauvahutanon P, Saengon P, Pongsanum P, Khamchu T, Chaimahapreuk S, Deoisares R, Jindayok T. Determination of factors associated with severity of COVID-19 patients in Naresuan University Hospital. Dis Control J [Internet]. 2023 Dec. 29 [cited 2024 Apr. 15];49(4):733-41. Available from:



Original Article