Use of inflammatory markers as predictor for mechanical ventilation in COVID-19 patients with stages IIIb-V chronic kidney disease?

Table 1 Demographic information, n (%)

Variables	Invasive mechanical ventilation	Non-invasive mechanical ventilation	No mechanical ventilation	Total	P valuea	P valueb
Age > 60 yr	24	25	62	111	1.00	1.00
	92.3	96.2	93.9	94.1
Male sex	18	12	26	56	0.01	0.55
	69.2	46.2	39.4	47.5
Vaccinated against COVID-19	2	7	16	25	0.13	0.16
	7.7	26.9	24.2	21.2
Hypertension	25	21	59	105	0.43	0.31
	96.2	80.8	89.4	89.0
Diabetes mellitus	15	13	33	61	0.51	1.00
	57.7	50.0	50.0	51.7
Chronic liver disease	0	1	1	2	1.00	0.49
	0.0	3.8	1.5	1.7
Chronic obstructive pulmonary disease	8	11	13	32	0.26	0.26
	30.8	42.3	19.7	27.1
Coronary artery disease	11	8	21	40	0.34	0.92
	42.3	30.8	31.8	33.9
Congestive heart failure	10	11	17	38	0.23	0.12
	38.5	42.3	25.8	32.2
Remdesivir	12	16	32	60	0.84	0.26
	46.2	61.5	48.5	50.8
Steroids	24	22	44	90	0.01	0.12
	92.3	84.6	66.7	76.3

^aChi square test between non mechanical ventilation and non invasive mechanical ventilation.

^bChi square test between non mechanical ventilation and invasive mechanical ventilation. COVID-19: Coronavirus disease 2019.

Table 2 Inflammatory marker levels between invasive mechanical ventilation and no mechanical ventilation, n (%)

Variables	Invasive mechanical ventilation	No mechanical ventilation	Total	P valuea
CRP level (mg/L)	17	17	48	0.01
	65.4	25.8	40.7
Ferritin level (ng/mL)	16	24	57	0.01
	61.5	36.4	48.3
LDH level (U/L)	7	3	12	0.04
	26.9	4.5	10.2
Troponin (ng/mL)	11	15	38	0.03
	42.3	22.7	32.2
D-dimer (mg/L)	21	34	76	0.01
	80.8	51.5	64.4

^aChi square test between non mechanical ventilation and non invasive mechanical ventilation. CRP: C reactive protein; LDH: Lactate dehydrogenase.

Table 3 Univariate analysis-invasive mechanical ventilation

Variables	OR	95%CI
CRP level	5.444	2.047-14.483
Ferritin level	2.8	1.098-7.138
LDH level	7.737	1.821-32.87
Troponin level	2.493	0.947-6.56
D-dimer level	3.953	1.331-11.74

CRP: C reactive protein; LDH: Lactate dehydrogenase; OR: Odds ratio; CI: Confidence interval.

Table 4 Inflammatory marker levels between non-invasive mechanical ventilation and no mechanical ventilation, n (%)

Variables	Non-invasive mechanical ventilation	No mechanical ventilation	Total	P valuea
CRP level (mg/L)	14	17	48	0.001
	53.8	25.8	40.7
Ferritin level (ng/mL)	17	24	57	0.03
	65.4	36.4	48.3
LDH level (U/L)	2	3	12	0.001
	7.7	4.5	10.2
Troponin (ng/mL)	12	15	38	0.06
	46.2	22.7	32.2
D-dimer (mg/L)	21	34	76	0.01
	80.8	51.5	64.4

^aChi square test between non mechanical ventilation and non invasive mechanical ventilation.

CRP: C reactive protein; LDH: Lactate dehydrogenase.

Table 5 Univariate analysis-non-invasive mechanical ventilation

Variables	OR	95%CI
CRP level	3.363	1.303-8.679
Ferritin level	3.306	1.277-8.55
LDH level	1.750	0.275-11.129
Troponin level	2.914	1.113-7.628
D-dimer level	3.953	1.331-11.736

CRP: C reactive protein; LDH: Lactate dehydrogenase; OR: Odds ratio; CI: Confidence interval.

Table 6 Area under the curve-invasive mechanical ventilation

Variables on admission	AUC	P value	95% confidence interval		Sensitivity (%)	Specificity (%)
			Lower limit	Upper limit
CRP level	0.747	0.001	0.617	0.878	80.8	51
Ferritin level	0.658	0.019	0.528	0.788	73	53
LDH level	0.699	0.003	0.579	0.820	80.8	51
D-dimer level	0.751	0.001	0.625	0.876	76.9	52

CRP: C reactive protein; LDH: Lactate dehydrogenase; AUC: Area under curve.

Table 7 Area under the curve-non invasive mechanical ventilation

Variables on admission	AUC	P value	95% confidence interval		Sensitivity (%)	Specificity (%)
			Lower limit	Upper limit
CRP level	0.663	0.015	0.527	0.799	69.2	53
Ferritin level	0.667	0.013	0.555	0.778	80.8	53
LDH level	0.573	0.280	0.445	0.700	61.5	55
D-dimer level	0.740	0.0004	0.620	0.860	80.8	50

CRP: C reactive protein; LDH: Lactate dehydrogenase; AUC: Area under curve.