Table 1.
Very preterm, n = 216 | Full-term, n = 45 | |
---|---|---|
Gestational age at birth in weeks, mean (SD), min to max | 27.5 (1.9), 22–32 | 39.0 (1.2), 37–41 |
Birthweight in grams, mean (SD), min to max | 959 (223), 414–1425 | 3307 (485), 2390–4290 |
Birthweight SD scorea, mean (SD) | −0.6 (0.9) | 0.1 (0.9) |
Small for gestational agea, n (%) | 19 (9) | 1 (2) |
Multiple birth, n (%) | 91 (42) | 2 (4) |
Male sex, n (%) | 112 (52) | 24 (53) |
Administered postnatal corticosteroids, n (%) | 21 (10)b | 0 (0) |
Bronchopulmonary dysplasiac, n (%) | 73 (34) | 0 (0) |
Infectiond, n (%) | 79 (37) | 0 (0) |
Moderate/Severe brain abnormalitye, n (%) | 58 (27)f | 0 (0) |
Cystic periventricular leucomalaciag, n (%) | 9 (4) | 0 (0) |
Intraventricular haemorrhage grade 3 or 4g, n (%) | 8 (4) | 0 (0)h |
Higher social risk at 2-year assessment, n (%) | 115 (61)i | 7 (17)j |
Postmenstrual age at neonatal MRI in weeks, mean (SD), min to max | 40.6 (1.0), 38–43k | 41.1 (0.9), 39–43l |
Age at 0-year MRI in years, mean (SD), min to max | 0.01 (0.03), −0.18–0.05k | 0.02 (0.02), −0.02–0.05l |
Weight at neonatal MRI in grams, mean (SD), min to max | 3024 (511), 1945–4678k | 3470 (472), 2530–4500m |
Age at 7-year MRI in years, mean (SD), min to max | 7.5 (0.3), 6.6–8.1n | 7.6 (0.2), 7.2–8.0l |
Weight at 7-year MRI in kg, mean (SD), min to max | 25 (5), 17–55o | 27 (5), 20–43l |
Age at 13-year MRI in years, mean (SD), min to max | 13.3 (0.4), 11.8–14.9p | 13.4 (0.6), 12.4–15.2q |
Weight at 13-year MRI in kg, mean (SD), min to max | 50 (12), 30–89r | 52 (14), 14–82s |
IQ at 13 years, mean (SD), min to max | 100 (18), 49–138t | 112 (13), 72–136l |
Higher social risk at 13-year assessment, n (%) | 98 (58)u | 5 (15)l |
All ages for the very preterm group have been corrected for prematurity.
SD standard deviation.
aBirthweight SD score was calculated relative to the British Growth Reference dataset. Small for gestational age was defined as birthweight more than two SDs below the mean. bn = 215. cBronchopulmonary dysplasia was defined as requirement for supplemental oxygen at 36 weeks. dInfection was defined as sepsis and/or proven necrotising enterocolitis. eScored on term-equivalent age MRI using the Kidokoro et al.25 qualitative reporting system. fn = 214. gCystic periventricular leucomalacia and intraventricular haemorrhage were recorded from cranial ultrasound; intraventricular haemorrhage was graded according to Papile et al.64. hn = 44. in = 188. jn = 41. kn = 193. ln = 34. mn = 33. nn = 152. on = 150. pn = 140. qn = 26. rn = 137. sn = 25. tn = 175. un = 168.