Table 2.

Factors associated with the risk of severe COVID-19, Mexico 2023.

Characteristic	$\mathbf{RR}(95\%\mathbf{CI}),\mathit{p}$
	Bivariate Analysis	Multivariate Analysis
Gender
Female	1.00	1.00
Male	1.05 (1.01–1.09), 0.008	1.03 (0.99–1.07), 0.082
Age (per each additional year)	1.003 (1.001–1.004), <0.001	1.002 (1.001–1.003), <0.001
COVID-19 vaccination status
Not vaccinated	1.00	1.00
One dose	0.96 (0.87–1.06), 0.437	0.95 (0.87–1.05), 0.342
Two doses	1.04 (0.98–1.09), 0.220	1.02 (0.97–1.08), 0.345
Three doses	1.23 (1.14–1.33), <0.001	1.19 (1.11–1.28), <0.001
Personal history of:
Obesity (BMI ≥ 30)
No	1.00	1.00
Yes	1.05 (0.99–1.10), 0.101	1.04 (0.99–1.09), 0.135
Smoking (current)
No	1.00	1.00
Yes	1.12 (1.02–1.22), 0.014	1.08 (0.99–1.17), 0.076
Type 2 diabetes mellitus
No	1.00	1.00
Yes	1.11 (1.05–1.16), <0.001	1.02 (0.97–1.07), 0.404
Cardiovascular disease
No	1.00	1.00
Yes	1.37 (1.22–1.53), <0.001	1.19 (1.06–1.33), 0.004
COPD
No	1.00	1.00
Yes	1.36 (1.23–1.51), <0.001	1.23 (1.11–1.37), <0.001
Asthma
No	1.00	1.00
Yes	1.02 (1.01–1.03), <0.001	1.04 (0.92–1.18), 0.556
CKD
No	1.00	1.00
Yes	1.20 (1.09–1.32), <0.001	1.12 (1.02–1.23), 0.020
Immunosuppression (any cause)
No	1.00	1.00
Yes	1.22 (1.08–1.39), 0.002	1.09 (0.96–1.23), 0.185

Abbreviations: COVID-19, coronavirus disease 2019; RR, risk ratio; CI, confidence interval; BMI, body mass index; COPD, chronic pulmonary obstructive disease; chronic kidney disease. Notes: (1) Generalized linear regression models were used to obtain the reported estimates; (2) The estimates from the multiple regression model were adjusted for all the variables presented in the table; (3) In the context of COVID-19 vaccination status, the unvaccinated group was selected as the reference to quantify the change in risk associated with receiving the vaccine.