Table 4 Multivariable logistic regression analysis of the association between pertussis vaccination and the clinical course and treatment of pertussis, stratified for term and preterm infants (crude and adjusted OR and 95% CI)
From: Pertussis hospitalizations among term and preterm infants: clinical course and vaccine effectiveness
| Probable and certain term infants (n = 481)a | Preterm infants (n = 60) | |||||||
|---|---|---|---|---|---|---|---|---|
| Unvaccinated infants (n = 268) | Vaccinated infants (n = 213) | crude OR (95% CI) | adjusted OR (95% CI)b | Unvaccinated infants (n = 23) | Vaccinated infants (n = 37) | crude OR (95% CI) | adjusted OR (95% CI)b | |
| Symptoms at admission | ||||||||
| Coughing attacks | 197 (73.5%) | 151 (70.9%) | 0.9 (0.6–1.3) | 0.8 (0.4–1.3) | 17 (73.9%) | 26 (70.3%) | 0.8 (0.3–2.7) | 0.8 (0.1–5.6) |
| Apnea | 47 (17.5%) | 22 (10.3%) | 0.5 (0.3–0.9) | 0.6 (0.3–1.1) | 10 (43.5%) | 5 (13.5%) | 0.2 (0.06–0.7) | 0.2 (0.03–1.5) |
| Whooping | 6 (2.2%) | 12 (5.6%) | 2.6 (0.96–7.1) | 1.8 (0.5–6.8) | 1 (4.4%) | 0 | < 0.001 (< 0.001- > 999.9) | 0.4 (< 0.001- > 999.9) |
| Vomiting | 94 (35.1%) | 79 (37.1%) | 1.1 (0.8–1.6) | 0.9 (0.6–1.6) | 8 (34.8%) | 13 (35.1%) | 1.0 (0.3–3.0) | 0.6 (0.1–3.3) |
| prolonged inspiratory effort | 15 (5.6%) | 19 (8.9%) | 1.7 (0.8–3.3) | 1.0 (0.4–2.3) | 1 (4.4%) | 4 (10.8%) | 2.7 (0.3–25.4) | 1.6 (0.1–26.1) |
| Collapse | 2 (0.8%) | 2 (0.9%) | 1.3 (0.2–9.0) | 7.2 (0.2–226.7) | 1 (4.4%) | 1 (2.7%) | 0.6 (0.04–10.3) | 0.6 (< 0.001- > 999.9) |
| Cyanosis | 126 (47.0%) | 88 (41.3%) | 0.8 (0.6–1.1)c | 1.1 (0.7–1.8)c | 5 (21.7%) | 17 (45.9%) | 3.1 (0.9–10.0)c | 1.9 (0.3–11.6)c |
| Fever | 17 (6.3%) | 21 (9.9%) | 1.6 (0.8–3.1) | 0.7 (0.3–1.7) | 2 (8.7%) | 4 (10.8%) | 1.3 (0.2–7.6) | > 999.9 (< 0.001- > 999.9) |
| Feeding problems | 87 (32.5%) | 63 (29.6%) | 0.9 (0.6–1.3) | 0.9 (0.5–1.4) | 10 (43.5%) | 12 (32.4%) | 0.6 (0.2–1.8) | 0.8 (0.2–4.5) |
| Complications | ||||||||
| Any complication | 30 (11.2%) | 9 (4.2%) | 0.4 (0.2–0.8) | 0.9 (0.4–2.5) | 5 (21.7%) | 3 (8.1%) | 0.3 (0.07–1.5) | 0.2 (0.01–4.6) |
| Treatment | ||||||||
| Antibiotics before admission | 37 (14.2%) | 52 (25.1%) | 1.8 (1.2–2.8) | 1.2 (0.7–2.1) | 2 (9.5%) | 9 (24.3%) | 2.7 (0.6–11.4) | 12.3 (0.8–188.3) |
| Antibiotics during admission | 230 (87.5%) | 157 (74.4%) | 0.4 (0.3–0.7) | 0.7 (0.4–1.3) | 21 (95.5%) | 32 (86.5%) | 0.3 (0.03–2.8) | 1.7 (0.1–23.7) |
| Artificial respiration | 23 (8.9%) | 5 (2.4%) | 0.3 (0.1–0.7) | 0.8 (0.2–3.4) | 7 (31.8%) | 2 (5.6%) | 0.1 (0.02–0.7) | 0.4 (0.02–5.7) |
| Additional oxygen | 133 (50.4%) | 33 (15.9%) | 0.2 (0.1–0.3) | 0.3 (0.2–0.5) | 13 (59.1%) | 10 (27.8%) | 0.2 (0.08–0.8) | 0.6 (0.09–4.0) |
| Admission intensive care unit (ICU) | 42 (15.7%) | 5 (2.4%) | 0.1 (0.05–0.3) | 0.3 (0.1–1.1) | 6 (26.1%) | 2 (5.4%) | 0.2 (0.03–0.9) | 0.6 (0.04–7.6) |
| Discharge | ||||||||
| Symptoms remaining | 206 (76.9%) | 162 (76.1%) | 0.9 (0.6–1.3) | 0.7 (0.5–1.2) | 14 (60.9%) | 30 (81.1% | 1.9 (0.7–5.1) | 2.1 (0.7–6.7) |