Table 4.

Crude and fully adjusted HR for mortality, respiratory failure, and ICU admission comparing patients by age group

Characteristic	HR	95% CI	p value
Mortality
Crude HR mortality	2.33	1.11, 2.57	<0.001
Fully adjusted HR for mortality
COVID-19 severitya
Mild	3.93	2.81, 5.50	<0.001
Severe	1.81	1.43, 2.93	<0.001
Critical	1.10	0.98, 1.24	0.106
Confounders
Hypertension	0.87	0.79, 0.96	0.006
Sex (male)	0.95	0.86, 1.05	0.304
Respiratory failure
Crude HR for respiratory failure	2.73	2.47, 3.01	<0.001
Fully adjusted HR for respiratory failure
COVID-19 severitya
Mild	2.65	1.92, 3.68	<0.001
Severe	1.27	1.01, 1.59	0.042
Critical	0.83	0.74, 0.94	0.003
Confounders
Smoker	1.31	1.14, 1.50	<0.001
Hypertension	1.93	1.72, 2.16	<0.001
Diabetes mellitus	1.30	1.16, 1.45	<0.001
Sex (male)	0.89	0.80, 0.99	0.026
ICU admission
Crude HR for ICU admission	2.56	2.33, 2.82	<0.001
Fully adjusted HR for respiratory failure
COVID-19 severitya
Mild	1.95	1.47, 2.59	<0.001
Severe	0.97	0.81, 1.17	0.770
Critical	0.84	0.74, 0.95	0.007
Confounders
Smoker	1.38	1.22, 1.58	<0.001
Hypertension	2.23	1.99, 2.49	<0.001
Diabetes mellitus	1.38	1.24, 1.53	<0.001
Sex (male)	0.92	0.83, 1.02	0.111

HR, hazard ratio; 95% CI, 95% confidence interval; COVID-19, coronavirus disease 2019; ICU, intensive care unit.

^aInteraction term/effect-measure modification: likelihood ratio test p value <0.001.