Skip to main content

Table 4 RR for asthma hospitalization and medication in childhood according to birth weight, gestational age and fetal growth in Denmark, 1993-2005

From: Birth weight, gestational age, fetal growth and childhood asthma hospitalization

Fetal development variables Asthma hospitalization Asthma medication
  Cases Cumulative incidence (%) Crude RR Adjusted RR* (95% CI) Cases Cumulative incidence (%) Crude RR Adjusted RR* (95% CI)
Birth weight         
  <1000 g 94 13.58 2.64 2.82 (2.12-3.74) 306 34.06 2.00 1.94 (1.75-2.15)
  1000-1499 g 184 9.01 1.91 1.71 (1.42-2.06) 624 27.12 1.63 1.51 (1.39-1.65)
  1500-1999 g 318 7.76 1.64 1.41 (1.21-1.64) 1,107 24.23 1.45 1.37 (1.28-1.47)
  2000-2499 g 812 6.87 1.46 1.30 (1.17-1.44) 2,950 22.30 1.34 1.29 (1.22-1.36)
  2500-2999 g 2,919 5.29 1.12 1.10 (1.03-1.18) 11,142 18.79 1.13 1.11 (1.07-1.16)
  3000-3499 g 8,099 5.01 1.06 1.07 (1.02-1.13) 30,145 16.89 1.02 1.01 (0.98-1.04)
  3500-3999 g 8,500 4.72 1 1 (ref) 32,242 16.43 1 1 (ref)
  4000-4499 g 4,045 4.89 1.04 1.01 (0.95-1.08) 14,984 16.55 1.00 0.99 (0.95-1.02)
  4500-4999 g 869 4.74 1.01 1.02 (0.92-1.12) 3,165 16.59 1.00 1.00 (0.95-1.05)
  ≥5000 g 135 5.56 1.18 1.15 (0.91-1.45) 463 16.48 1.01 0.99 (0.89-1.08)
Birth weight per 1000-g decrease - - 1.17 1.15 (1.11-1.19) - - 1.13 1.11 (1.10-1.13)
Gestational age         
  22-28 weeks 129 11.72 2.34 2.37 (1.87-2.99) 412 30.69 1.86 1.78 (1.64-1.94)
  29-32 weeks 301 8.65 1.79 1.49 (1.29-1.72) 1,084 25.67 1.56 1.45 (1.36-1.54)
  33-36 weeks 1,318 6.36 1.32 1.20 (1.10-1.30) 5,021 21.90 1.33 1.26 (1.22-1.30)
  37-38 weeks 4,464 5.67 1.17 1.14 (1.08-1.21) 16,967 18.69 1.13 1.10 (1.08-1.13)
  39-41 weeks 17,616 4.79 1 1 (ref) 65,682 16.44 1 1 (ref)
  42-45 weeks 2,147 4.61 0.96 0.94 (0.88-1.01) 7,962 17.40 1.05 1.05 (0.95-1.16)
GA per reduced week - - 1.06 1.05 (1.04-1.06) - - 1.04 1.04 (1.03-1.05)
Birth weight for gestational age         
  SGA 1,055 6.36 1.29 1.20 (1.10-1.31) 3,776 21.15 1.25 1.19 (1.14-1.24)
  AGA 23,784 4.94 1 1 (ref) 89,263 17.02 1 1 (ref)
  LGA 1,136 5.32 1.07 1.11 (0.99-1.24) 4,089 17.34 1.02 1.04 (0.99-1.09)
Z-score per decreased of SD - - 1.03 1.01 (0.99-1.03) - - 1.03 1.02 (1.01-1.03)
  1. *Adjusted for maternal age at delivery, maternal social status, parity, mode of delivery, sex of the child, calendar year of birth and family history of asthma.