Bibian van der Voorn

130 CHAPTER 9 FIGURE 2. Serum cortisol (means): SGA vs. AGA infants (A), growth birth-6 mo. corrected age (AGA GR–, AGA GR+, SGA CUG–, and SGA CUG+) (B). Abbreviations: AGA GR+/GR–, appropriate for gestational age with or without growth restriction at 6 mo. corrected age; SGA CUG+/CUG–, small for gestational age with or without catch-up growth at 6 mo. corrected age a SGA vs. AGA p=0.08, b SGA CUG– vs. AGA GR– p=0.02, c SGA CUG+ vs. AGA GR– p=0.08, d SGA CUG– vs. AGA GR– p=0.08. All P-values represent unadjusted cross-sectional analyses. TABLE 3. Serum cortisol (nmol/L), mean ± SD at every sampling moment n Term age n 3 mo. corrected age n 6 mo. corrected age n 8 y Birth weight SDS, continuous 150 367.3 ± 175.4 145 328.1 ± 148.9 144 319.8 ± 127.1 59 241.2 ± 113.5 SGA AGA 108 367.3 ± 175.6 103 337.7 ± 143.1 a 103 323.0 ± 126.1 43 233.7 ± 114.8 SGA 35 339.0 ± 166.2 34 287.9 ± 143.6 34 291.1 ± 120.5 14 265.2 ± 117.5 Early postnatal growth AGA GR– 95 372.0 ± 179.1 95 343.6 ± 146.2 95 326.5 ± 129.5 38 229.2 ± 106.8 AGA GR+ 8 296.0 ± 117.6 8 268.5 ± 73.8 8 268.7 ± 64.3 5 267.6 ± 177.1 SGA CUG– 14 256.3 ± 157.3 b 14 313.4 ± 110.5 14 262.4 ± 119.8 d 6 236.7 ± 84.8 SGA CUG+ 20 384.2 ± 148.2 19 281.2 ± 159.8 c 20 311.2 ± 119.8 8 286.6 ± 138.8 Abbreviations: AGA, appropriate for gestational age (birth weight and birth length >–2SDS); CUG, catch-up growth; GR, growth restriction; SGA, small for gestational age (birth weight and/or birth length ≤–2SDS). a SGA vs. AGA p =0.08, b SGA CUG– vs. AGA GR– p =0.02, c SGA CUG+ vs. AGA GR– p =0.08, d SGA CUG– vs. AGA GR– p =0.08. All P-values represent unadjusted cross-sectional analyses. LONGITUDINAL ANALYSES GEE The results of the longitudinal analyses are presented in Table 4 . A birthweight <0 SDSwas associatedwith lower cortisol as compared to a birthweight ≥0 SDS. (–17.33 [ –30.96 to –3.69], P=0.01). A birth weight ≤–2 SDS was associated with a lower cortisol over time, compared to a birth weight >–2 SDS (–50.69 [–94.27 to –7.11], P=0.02). Being born SGA was associated with lower cortisol over time, as compared to being born AGA (–29.70 [ –60.58 to 1.19], P=0.05). At 6 mo. corrected age, AGA GR+ and SGA CUG – infants had lower cortisol over time compared to AGA GR– infants (–55.10 [–106.02 to –4.17], P = 0.03, and –61.91 [ –104.73 to –19.10], P = 0.01, respectively). No differences in cortisol over time were found between SGA CUG+ and AGA GR– infants.