Table 3. Subgroup analyses.
Hazard ratios for incidence of non-COVID-19 death stratified by age group, clinical vulnerability status, and prior infection status in the (A) two-dose analysis and (B) three-dose analysis.
| (A) Two-dose analysis | Two-dose cohort* | Unvaccinated cohort* |
|---|---|---|
| Age | ||
| <50 years of age | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.91 (0.73–1.12) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 0.89 (0.72–1.11) | |
| ≥50 years of age | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.59 (0.44–0.78) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 0.56 (0.42–0.75) | |
| Clinical vulnerability status | ||
| Less clinically vulnerable to severe COVID-19 | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.99 (0.80–1.23) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 0.98 (0.79–1.22) | |
| More clinically vulnerable to severe COVID-19 | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.53 (0.41–0.70) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 0.51 (0.39–0.68) | |
| Prior infection status | ||
| No prior infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.76 (0.64–0.90) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 0.74 (0.63–0.89) | |
| Prior pre-omicron infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 1.05 (0.48–2.30) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | 1.00 (0.45–2.20) | |
| Prior omicron infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | -- ‡ | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | -- ‡ | |
| Prior pre-omicron & omicron infections | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | -- ‡ | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)† | -- ‡ | |
| (B) Three-dose analysis | Three-dose cohort § | Two-dose cohort § |
| Age | ||
| <50 years of age | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.90 (0.67–1.21) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 0.90 (0.67–1.20) | |
| ≥50 years of age | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.80 (0.54–1.18) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 0.76 (0.51–1.13) | |
| Clinical vulnerability status | ||
| Less clinically vulnerable to severe COVID-19 | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.91 (0.68–1.23) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 0.91 (0.67–1.22) | |
| More clinically vulnerable to severe COVID-19 | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.78 (0.54–1.15) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 0.76 (0.52–1.12) | |
| Prior infection status | ||
| No prior infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 0.80 (0.63–1.03) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 0.79 (0.61–1.01) | |
| Prior pre-omicron infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 1.63 (0.71–3.73) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 1.63 (0.71–3.72) | |
| Prior omicron infection | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | 1.32 (0.30–5.90) | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | 1.32 (0.30–5.91) | |
| Prior pre-omicron & omicron infections | ||
| Unadjusted hazard ratio for non-COVID-19 death (95% CI) | -- ‡ | |
| Adjusted hazard ratio for non-COVID-19 death (95% CI)¶ | -- ‡ | |
CI, confidence interval; COVID-19, coronavirus disease 2019; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
Cohorts were matched exactly one-to-one by sex, 10-year age group, nationality, type of coexisting conditions, and prior infection status. Persons who received their second vaccine dose in a specific calendar week in the two-dose cohort were additionally matched to persons who had a record for a SARS-CoV-2-negative test in that same calendar week in the unvaccinated cohort, to ensure that matched pairs had presence in Qatar over the same time period.
Adjusted for sex, 10-year age group, nationality, number of coexisting conditions, prior infection status (where applicable), and calendar week of the second vaccine dose for the two-dose cohort or SARS-CoV-2-negative test for the unvaccinated cohort.
Could not be estimated because of no or small number of events.
Cohorts were matched exactly one-to-one by sex, 10-year age group, nationality, type of coexisting conditions, prior infection status, and calendar week of the second vaccine dose. Persons who received their third vaccine dose in a specific calendar week in the three-dose cohort were additionally matched to persons who had a record for a SARS-CoV-2-negative test in that same calendar week in the two-dose cohort, to ensure that matched pairs had presence in Qatar over the same time period.
Adjusted for sex, 10-year age group, nationality, number of coexisting conditions, prior infection status (where applicable), and calendar week of the second vaccine dose.