Table 1.
Association between covariates and infection during childhood
| No infection | Any infection | p value | ||
|---|---|---|---|---|
| N | 274,137 | 282,595 | ||
| Sex | Male | 137,874 (50.3%) | 147,580 (52.2%) | <0.001 |
| Female | 136,263 (49.7%) | 135,015 (47.8%) | ||
| Birth order | First | 120,946 (44.1%) | 130,474 (46.2%) | <0.001 |
| Second | 100,348 (36.6%) | 100,812 (35.7%) | ||
| ≥Third | 52,843 (19.3%) | 51,309 (18.2%) | ||
| Season of birth | Dec–Feb | 63,102 (23.0%) | 67,535 (23.9%) | <0.001 |
| Mar–May | 76,236 (27.8%) | 74,189 (26.3%) | ||
| Jun–Aug | 71,724 (26.2%) | 72,737 (25.7%) | ||
| Sep–Nov | 63,075 (23.0%) | 68,134 (24.1%) | ||
| GA | Preterm | 12,538 (4.6%) | 18,647 (6.6%) | <0.001 |
| Term | 259,245 (94.6%) | 261,986 (92.7%) | ||
| Post term | 1868 (0.7%) | 1507 (0.5%) | ||
| Missing | 486 (0.2%) | 455 (0.2%) | ||
| Size for GA | Small | 5955 (2.2%) | 7154 (2.5%) | <0.001 |
| Normal | 252,060 (91.9%) | 256,864 (90.9%) | ||
| Large | 7756 (2.8%) | 8866 (3.1%) | ||
| Missing | 8366 (3.1%) | 9711 (3.4%) | ||
| Cesarean delivery | No | 250,805 (91.5%) | 250,794 (88.7%) | <0.001 |
| Yes | 14,966 (5.5%) | 22,090 (7.8%) | ||
| Missing | 8366 (3.1%) | 9711 (3.4%) | ||
| Low Apgar score (<7) | No | 268,435 (97.9%) | 276,398 (97.8%) | <0.001 |
| Yes | 2069 (0.8%) | 3010 (1.1%) | ||
| Missing | 3633 (1.3%) | 3187 (1.1%) | ||
| Pre-eclampsia | No | 267,511 (97.6%) | 274,246 (97.0%) | <0.001 |
| Yes | 6626 (2.4%) | 8349 (3.0%) | ||
| Maternal BMI | Underweight | 7742 (2.8%) | 7358 (2.6%) | <0.001 |
| Normal weight | 136,642 (49.8%) | 145,232 (51.4%) | ||
| Overweight | 35,625 (13.0%) | 45,130 (16.0%) | ||
| Obese | 10,994 (4.0%) | 16,576 (5.9%) | ||
| Missing | 83,134 (30.3%) | 68,299 (24.2%) | ||
| Maternal age | <25 | 39,398 (14.4%) | 43,294 (15.3%) | <0.001 |
| 25–29 | 81,387 (29.7%) | 82,534 (29.2%) | ||
| 30–34 | 95,776 (34.9%) | 97,574 (34.5%) | ||
| 35–39 | 47,716 (17.4%) | 48,881 (17.3%) | ||
| >39 | 9860 (3.6%) | 10,312 (3.6%) | ||
| Paternal age | <25 | 18,213 (6.7%) | 19,849 (7.1%) | <0.001 |
| 25–29 | 59,360 (21.9%) | 61,309 (21.9%) | ||
| 30–34 | 91,088 (33.6%) | 93,622 (33.5%) | ||
| 35–39 | 63,265 (23.3%) | 64,659 (23.1%) | ||
| >39 | 39,336 (14.5%) | 40,240 (14.4%) | ||
| Mother’s region of origin | Sweden | 205,870 (75.1%) | 202,203 (71.6%) | <0.001 |
| Nordic | 8595 (3.1%) | 6840 (2.4%) | ||
| West Eu and NA | 12,282 (4.5%) | 12,224 (4.3%) | ||
| Africa | 11,013 (4.0%) | 14,602 (5.2%) | ||
| Asia and Oceania | 5423 (2.0%) | 6239 (2.2%) | ||
| Middle-East | 19,195 (7.0%) | 27,227 (9.6%) | ||
| East Eu and Russia | 3640 (1.3%) | 3822 (1.4%) | ||
| South America | 5230 (1.9%) | 6502 (2.3%) | ||
| Unknown/missing | 2889 (1.1%) | 2936 (1.0%) | ||
| Father’s region of origin | Sweden | 209,664 (76.5%) | 208,152 (73.7%) | <0.001 |
| Nordic | 11,306 (4.1%) | 8510 (3.0%) | ||
| West Eu and NA | 8137 (3.0%) | 8203 (2.9%) | ||
| Africa | 9342 (3.4%) | 12,877 (4.6%) | ||
| Asia and Oceania | 8740 (3.2%) | 8820 (3.1%) | ||
| Middle-East | 16,377 (6.0%) | 23,586 (8.3%) | ||
| East Eu and Russia | 5821 (2.1%) | 6307 (2.2%) | ||
| South America | 4738 (1.7%) | 6135 (2.2%) | ||
| Unknown/missing | 12 (<1%) | 5 (<1%) | ||
| Maternal psychiatric diagnosis | No | 165,792 (60.5%) | 148,803 (52.7%) | <0.001 |
| Yes | 108,345 (39.5%) | 133,792 (47.3%) | ||
| Paternal psychiatric diagnosis | No | 203,417 (74.2%) | 200,609 (71.0%) | <0.001 |
| Yes | 70720 (25.8%) | 81,986 (29.0%) | ||
| Maternal infection | No | 129,656 (47.3%) | 92,021 (32.6%) | <0.001 |
| Yes | 144,481 (52.7%) | 190,574 (67.4%) | ||
| Paternal infection | No | 171,631 (62.6%) | 150,049 (53.1%) | <0.001 |
| Yes | 102,506 (37.4%) | 132,546 (46.9%) | ||
| Family income | Low (0–20%) | 39,139 (14.3%) | 40,758 (14.4%) | <0.001 |
| 20–40% | 55,086 (20.1%) | 62,326 (22.1%) | ||
| 40–60% | 58,526 (21.3%) | 62,289 (22.0%) | ||
| 60–80% | 59,933 (21.9%) | 59,787 (21.2%) | ||
| High (80–100%) | 61,126 (22.3%) | 57,027 (20.2%) | ||
| Missing | 327 (0.1%) | 408 (0.1%) | ||
| Parental education | <10 years | 15,585 (5.7%) | 18,908 (6.7%) | <0.001 |
| 10–12 | 103,202 (37.6%) | 109,598 (38.8%) | ||
| >12 | 154,608 (56.4%) | 153,380 (54.3%) | ||
| Missing | 742 (0.3%) | 709 (0.3%) | ||
| ASD | No ASD | 268,334 (97.9%) | 273,793 (96.9%) | <0.001 |
| 0–<6 years | 1132 (0.4%) | 2572 (0.9%) | ||
| 6–<12 years | 2257 (0.8%) | 3588 (1.3%) | ||
| 12–18 years | 2414 (0.9%) | 2642 (0.9%) | ||
| ID | No ID | 272,086 (99.3%) | 278,130 (98.4%) | <0.001 |
| 0–<6 years | 524 (0.2%) | 1886 (0.7%) | ||
| 6–<12 years | 908 (0.3%) | 1802 (0.6%) | ||
| 12–18 years | 619 (0.2%) | 777 (0.3%) |
GA gestational age, NA North America, Eu Europe, ASD autism spectrum disorder, ID intellectual disability