Estimated associations between influenza vaccination status and COVID-19-related mortality
| Outcome | Patient death | ||||
| (1) | (2) | (3) | (4) | (5)† | |
| Influenza vaccine | 0.640*** | 0.822*** | 0.822*** | 0.840*** | 0.838*** |
| (0.578 to 0.710) | (0.762 to 0.887) | (0.761 to 0.887) | (0.779 to 0.906) | (0.773 to 0.910) | |
| Cardiovascular condition | 0.960 | 0.963 | 0.954 | ||
| (0.894 to 1.030) | (0.897 to 1.034) | (0.882 to 1.033) | |||
| Haematological condition | 1.041 | 1.042 | 1.034 | ||
| (0.812 to 1.335) | (0.811 to 1.338) | (0.786 to 1.361) | |||
| Liver condition | 1.287** | 1.234* | 1.250* | ||
| (1.015 to 1.633) | (0.970 to 1.569) | (0.966 to 1.618) | |||
| Asthma | 0.802*** | 0.845** | 0.844** | ||
| (0.700 to 0.919) | (0.736 to 0.970) | (0.726 to 0.980) | |||
| Diabetes | 1.055 | 1.061* | 1.050 | ||
| (0.984 to 1.130) | (0.989 to 1.137) | (0.974 to 1.132) | |||
| Neurological disorders | 1.224*** | 1.226*** | 1.256*** | ||
| (1.075 to 1.395) | (1.077 to 1.396) | (1.087 to 1.452) | |||
| Respiratory conditions | 1.154** | 1.149** | 1.155** | ||
| (1.014 to 1.313) | (1.010 to 1.307) | (1.002 to 1.331) | |||
| Immunosuppressed | 1.211*** | 1.232*** | 1.223** | ||
| (1.051 to 1.396) | (1.069 to 1.421) | (1.040 to 1.439) | |||
| Renal condition | 1.282*** | 1.262*** | 1.267*** | ||
| (1.136 to 1.446) | (1.119 to 1.424) | (1.112 to 1.443) | |||
| Obese | 1.276*** | 1.301*** | 1.348*** | ||
| (1.121 to 1.454) | (1.142 to 1.483) | (1.172 to 1.551) | |||
| Observations | 40 394 | 36 543 | 36 543 | 36 543 | 29 572 |
Table 2 compares patient mortality among vaccinated and non-vaccinated patients, conditioning on an increasing number of covariates. Estimates are based on multivariable logistic regression models. Estimated numbers displayed are ORs with 95% CIs in parentheses. SEs are adjusted for clustering at the facility level using the Huber-White cluster-robust variance estimator. Survival status was not available for 13 358 cases. Column 1 controls for age only. Column 2 controls for age and treatment facility. Three thousand eight hundred fifty-one observations were dropped in columns 2–5 because either all patients in a given facility survived or died (insufficient variation). Column 3 controls for age, facility and comorbidities. Column 4 controls for age, facility, comorbidities and patient’s SES. Age controls correspond to separate binary indicator variables for each 10-year age group. SES controls include gender, race and educational attainment group. Missing data on comorbidities and SES were imputed using multiple imputations using chained equations.
*p<0.10; **p<0.05; ***p<0.01.
†Restricted to observations with confirmed positive RT-qPCR result for SARS-CoV-2.
SES, socioeconomic status.