Table 1.
Characteristics of adults aged ≥70 years in São Paulo state, Brazil, who were eligible for matching and selected into case test negative pairs. Values are numbers (percentages) unless stated otherwise
| Characteristics | Eligible cases and controls | Matched sets | |||
|---|---|---|---|---|---|
| Test negative (n=17 622)* | Test positive (n=26 433)* | Controls (n=42 236)* | Cases (n=13 283)* | ||
| Mean (SD) age (years) | 77.53 (6.8) | 76.71 (6.2) | 75.69 (5.44) | 75.90 (5.64) | |
| Age groups (years): | |||||
| 70-79 | 12 123 (68.8) | 19 673 (74.4) | 34134 (80.8) | 10543 (79.4) | |
| 80-89 | 4301 (24.4) | 5437 (20.6) | 7045 (16.7) | 2311 (17.4) | |
| ≥90 | 1198 (6.8) | 1323 (5.0) | 1057 (2.5) | 429 (3.2) | |
| Men | 7689 (43.6) | 12 431 (47.0) | 18610 (44.1) | 5919 (44.6) | |
| Self-reported race†: | |||||
| White/branca | 13 415 (76.1) | 19 796 (74.9) | 34603 (81.9) | 10803 (81.3) | |
| Brown/pardo | 3192 (18.1) | 4983 (18.9) | 6797 (16.1) | 2115 (15.9) | |
| Black/preta | 785 (4.5) | 1258 (4.8) | 727 (1.7) | 287 (2.2) | |
| Yellow/amarela | 226 (1.3) | 390 (1.5) | 109 (0.3) | 78 (0.6) | |
| Indigenous/Indígena | 4 (0.0) | 6 (0.0) | - | - | |
| Residence in Grande São Paul health region | 12 381 (70.3) | 16 538 (62.6) | 14368 (34.0) | 6113 (46.0) | |
| Reported No of comorbidities‡: | |||||
| 0 | 10 027 (56.9) | 12 668 (47.9) | 23961 (56.7) | 5886 (44.3) | |
| 1 or 2 | 6984 (39.6) | 12 548 (47.5) | 16626 (39.4) | 6713 (50.5) | |
| ≥3 | 611 (3.5) | 1217 (4.6) | 1649 (3.9) | 684 (5.1) | |
| Cardiovascular disease | 5293 (30.0) | 10 079 (38.1) | 12563 (29.7) | 5482 (41.3) | |
| Diabetes | 3233 (18.3) | 6533 (24.7) | 8269 (19.6) | 3578 (26.9) | |
| Past exposure to SARS-CoV-2§ | |||||
| Previous symptomatic events notified to surveillance systems¶ | 685 (3.9) | 354 (1.3) | 47 (0.1) | 37 (0.3) | |
| Positive SARS-CoV-2 test result** | 66 (0.4) | 13 (0.0) | 1 (0.0) | 4 (0.0) | |
| Median (interquartile range) interval between symptoms onset and RT-PCR testing (days) | 3 (2-5) | 4 (2-6) | 3 (1-5) | 4 (2-6) | |
| Hospital admissions | 4524/17 484 (25.9) | 12 987/26 221 (49.5) | 11 020/41 980 (26.3) | 7043/13 175 (53.5) | |
| Deaths | 1594/16 710 (9.5) | 7054/24 508 (28.8) | 4072/40 134 (10.1) | 3549/12 251 (29.0) | |
| Median (interquartile range) interval between symptoms onset and hospital admission (days) | 3 (2-6) | 7 (4-10) | 4 (2-7) | 7 (4-10) | |
| Median (interquartile range) interval between symptoms onset and deaths (days) | 8 (4-13) | 14 (9-21) | 8 (4-16) | 15 (10-22) | |
| Vaccination status: | |||||
| Not vaccinated | 11 986 (68.0) | 17 233 (65.2) | 27994 (66.3) | 8989 (67.7) | |
| Single dose, within 0-13 days | 1446 (8.2) | 2976 (11.3) | 4873 (11.5) | 1565 (11.8) | |
| Single dose, ≥14 days | 1797 (10.2) | 3312 (12.5) | 4631 (11.0) | 1489 (11.2) | |
| Two doses, within 0-13 days | 1041 (5.9) | 1533 (5.8) | 2445 (5.8) | 700 (5.3) | |
| Two doses, ≥14 days | 1352 (7.7) | 1379 (5.2) | 2293 (5.4) | 540 (4.1) | |
| Mean (SD) interval between 1st and 2nd dose (days) | 25 (6) | 30 (12) | 25 (6) | 30 (12) | |
| Mean (SD) interval between 1st dose and RT-PCR testing (days) | 28 (19) | 23 (16) | 22 (17) | 21 (16) | |
| Mean (SD) interval between second dose and RT-PCR testing (days) | 20 (15) | 17 (14) | 17 (14) | 16 (14) | |
RT-PCR=reverse transcription polymerase chain reaction.
Numbers refer to RT-PCR tests and represent 43 774 people for the eligible cases and controls and 22 177 people in matched cases and controls.
Race/skin colour as defined by the Brazilian national census bureau (Instituto Nacional de Geografia e Estatísticas).32
Comorbidities included cardiovascular, renal, neurological, haematological, or hepatic conditions, diabetes, chronic respiratory disorder, obesity, or immunosuppression.
Before start of study on 17 January 2021 and after systematic surveillance was implemented on 1 February 2020.
Reported illness with covid-19 associated symptoms in eSUS and SIVEP-Gripe databases.
Defined as a positive SARS-CoV-2 RT-PCR or antigen detection test result.