Relative risk (RR) for wheeze and related outcomes at age 5 years with prenatal acetaminophen exposure (n=297*)
| Reported days of acetaminophen use in pregnancy | p Value for trend | |||||
| 0 (n=198) | 1 (n=37) | 2–4 (n=37) | ≥5 (n=25) | |||
| Current wheeze | No (%) | 41 (21) | 11 (30) | 14 (38) | 13 (52) | <0.001 |
| Crude RR (95% CI) | 1 (reference) | 1.44 (0.82 to 2.53) | 1.83 (1.11 to 3.00) | 2.51 (1.58 to 4.00) | ||
| Adjusted† RR (95% CI) | 1 (reference) | 1.06 (0.55 to 2.03) | 1.95 (1.29 to 2.96) | 2.26 (1.40 to 3.63) | <0.001 | |
| Persistent wheeze‡ | No (%) | 34 (17) | 9 (24) | 12 (32) | 9 (36) | 0.008 |
| Crude RR (95% CI) | 1 (reference) | 1.42 (0.74 to 2.70) | 1.89 (1.10 to 3.30) | 2.10 (1.14 to 3.84) | ||
| Adjusted RR (95% CI) | 1 (reference) | 1.29 (0.72 to 2.32) | 1.94 (1.22 to 3.08) | 1.90 (1.15 to 3.15) | 0.009 | |
| Sleep disturbed by wheeze | No (%) | 30 (15) | 4 (11) | 10 (27) | 9 (36) | 0.005 |
| Crude RR (95% CI) | 1 (reference) | 0.71 (0.27 to 1.91) | 1.78 (0.96 to 3.32) | 2.38 (1.28 to 4.41) | ||
| Adjusted RR (95% CI) | 1 (reference) | 0.48 (0.14 to 1.62) | 2.05 (1.21 to 3.47) | 2.39 (1.31 to 4.34) | 0.005 | |
| Took medication for wheeze or difficulty breathing | No (%) | 46 (23) | 13 (35) | 15 (41) | 13 (52) | 0.001 |
| Crude RR (95% CI) | 1 (reference) | 1.51 (0.91 to 2.51) | 1.74 (1.10 to 2.78) | 2.24 (1.42 to 3.52) | ||
| Adjusted RR (95% CI) | 1 (reference) | 1.24 (0.72 to 2.11) | 1.97 (1.34 to 2.89) | 2.18 (1.40 to 3.42) | <0.001 | |
| Emergency department or emergency visit to a physician for asthma, wheeze or other breathing problem | No (%) | 31 (16) | 10 (27) | 12 (32) | 7 (28) | 0.034 |
| Crude RR (95% CI) | 1 (reference) | 1.73 (0.93 to 3.21) | 2.07 (1.17 to 3.64) | 1.79 (0.88 to 3.63) | ||
| Adjusted RR (95% CI) | 1 (reference) | 1.69 (0.93 to 3.09) | 3.03 (1.89 to 4.87) | 2.16 (1.14 to 4.10) | 0.014 | |
| Seroatopy§ | No (%) | 37/143¶(26) | 11/30 (37) | 9/27 (33) | 11/21 (52) | 0.013 |
| Crude RR (95% CI) | 1 (reference) | 1.42 (0.82 to 2.45) | 1.29 (0.71 to 2.35) | 2.02 (1.24 to 3.32) | ||
| Adjusted RR (95% CI) | 1 (reference) | 1.21 (0.68 to 2.36) | 1.32 (0.81 to 2.16) | 1.99 (1.36 to 2.91) | <0.001 | |
↵* The four mothers who reported acetaminophen use during pregnancy but did not report the number of days of use were excluded from this table.
↵† Relative risks were adjusted for sex, ethnicity, birth order, maternal asthma, maternal hardship, exposure to environmental tobacco smoke and postnatal acetaminophen use.
↵‡ Wheeze was reported at least once between birth, age 3 years AND in the past 12 months at age 5 years.
↵§ Child had specific IgE (>0.35 IU/ml) to at least one allergen tested: dust mite (Dermatophagoides farinae), cockroach, mouse, cat or dog.
↵¶ The number of children on whom IgE was measured was lower (n=221) than those with symptom data at age 5.