Table 6. Multivariate analysis of clinical and immunogenetic factors associated with the severity of the SARS-CoV-2 disease course.

Characteristics of Sardinian COVID-19 patients	Total patients (N = 396)		Group A (N = 240)		Group S (N = 156)		Comparisons of Group S vs Group A
							Univariate Analysis			Multivariate analysis
	n	%	n	%	n	%	OR	95% CI	PU*	ORM#	95% CIM§	PM*	PMC*
Age ≥ 65 yr	120	30.3	48	20.0	72	46.2	3.4	2.1–5.5	5.5·10−8	5.0	3.0–8.5	1.2·10−9	1.2·10−8
Male gender	195	49.2	84	35.0	111	71.2	4.6	2.9–7.3	1.6·10−12	6.2	3.8–10.3	4.1·10−13	4.1·10−12
FLU vaccine 2019	52	13.1	39	16.3	13	8.3	0.5	0.2–0.9	0.023	0.5	0.2–0.9	0.037
Autoimmune disease&	75	18.9	33	13.7	42	26.9	2.3	1.3–4.0	0.002	3.2	1.7–6.1	4.0·10−4	4.0·10−3
KIR haplotype AA	111	28.0	57	23.8	54	34.6	1.7	1.1–2.7	0.02	1.5	0.9–2.5	0.110
KIR2DS2+/HLA C1+	172	43.4	120	50.0	52	33.3	0.5	0.3–0.8	0.001	0.4	0.3–0.7	4.6·10−4	4.6·10−3
KIR2DL2+/HLA C1+	177	44.7	120	50.0	57	36.5	0.6	0.4–0.9	0.01	0.5	0.3–0.9	0.011
KIR2DS2	244	61.6	162	67.5	82	52.6	0.5	0.3–0.8	0.003	0.6	0.4–0.9	0.03
KIR2DL2	249	62.9	162	67.5	87	55.8	0.6	0.4–0.9	0.02	0.7	0.4–1.2	0.170
cA01/cA01	144	36.4	75	31.3	69	44.2	1.7	1.1–2.7	0.01	1.5	0.9–2.4	0.092

In the comparisons between Group S and Group A, age and gender were the most relevant factors. Therefore, the odds ratios of all variables were adjusted accordingly. The Table shows the adjusted odds ratios of the variables which in univariate analysis resulted to be significantly different in the two groups of patients.

*P_U = P value in univariate analysis; P_M = P value in multivariate regression analysis. P_MC = P value in multivariate analysis after correction for multiple tests.

^#OR_M = Odds ratio adjusted for age and gender; ^§95% CI_M = 95% confidence interval calculated using the logistic regression model

^&rheumatoid arthritis, type I diabetes mellitus and autoimmune hepatitis; + = present.