Dose-response relationship between risk factors and incidence of COVID-19 in 325 hospitalized patients: A multicenter retrospective cohort study

Table 5 Associations of risk factors with incident mortality risk of coronavirus disease 2019

Variable	HR (95%CI)		P for overall association	P for nonlinear association
	Model 1	Model 2
Age (per year increase)	1.06 (1.03, 1.10)	1.04 (1.01, 1.09)	0.080	0.805
CRP (per 1 mg/L increase)	1.15 (1.06, 1.24)	1.10 (1.01, 1.23)	0.062	0.715
DD (per 1 μg/mL increase of NLT	1.89 (1.34, 2.69)	1.63 (1.03, 2.58)	0.012	0.711
LDH (per 10 U/L increase)	1.06 (1.02, 1.09)	1.04 (1.01, 1.10)	0.080	0.805
Procalcitonin (per 1 ng/mL increase of NLT)	2.15 (1.59, 2.90)	1.88 (1.22, 2.88)	0.011	0.721

Hazard ratios are reported per 1-SD increase in loge D-dimer (DD) and Procalcitonin levels; 1-SD higher loge DD and Procalcitonin was approximately equivalent to 2-fold higher DD and Procalcitonin levels.

Model 1: adjusted age, sex.

Model 2: adjusted model 1 plus smoking status, history of hypertension, diabetes, cancers, cardiac disease, and chronic pulmonary disease, systolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, white blood cell count, C-reactive protein, creatinine, DD, LDH, procalcitonin. CRP: C-reactive protein; DD: D-dimer; LDH: Lactate dehydrogenase; NLT: Natural log-transformation; CI: Confidence interval.