TABLE 2.

Characteristics of Follow-up Cohort by Weight Gain Quartile

VariableaQuartile 1 (n = 124)Quartile 2 (n = 122)Quartile 3 (n = 123)Quartile 4 (n = 121)Pb
Weight gain, mean (SD), g/kg per d12.0 (2.1)15.6 (0.8)17.8 (0.8)21.2 (2.0)
Length growth, cm/wk0.82 (0.3)0.91 (0.2)1.00 (0.2)1.11 (0.3)
Head circumference growth, cm/wk0.77 (0.2)0.90 (0.2)0.96 (0.1)1.07 (0.2)
Birth weight, g799 (132)804 (128)795 (128)804 (130).92
Weight at status, gc1855 (305)1974 (206)1976 (218)1978 (207).0006
Length at status, cm41.5 (2.4)41.8 (1.7)41.6 (1.7)41.7 (1.7).83
Head circumference at status, cm31.2 (1.9)31.6 (1.4)31.6 (1.3)31.4 (1.3).64
Gestational age, wk26.3 (1.9)26.3 (1.9)26.2 (1.8)26.7 (2.4).56
Postmenstrual age at status, wk38.3 (3.7)37.4 (2.4)36.5 (2.0)36.0 (2.0)<.0001
Postnatal age at status, d86.3 (25.1)80.4 (18.2)74.7 (17.0)68.2 (17.0)<.0001
Age at regaining birth weight, d15.9 (11.0)17.3 (9.9)18.8 (8.5)19.5 (9.1).0031
Regained birth weight >18 days, %35405049<.01
Time from regaining birth weight to status, d72.0 (21.9)63.6 (16.5)56.9 (16.0)50.9 (14.0)<.0001
Female, %48484860.097
Race, %.64
    Black44485550
    White (and other)44423338
    Hispanic12101212
SGA, %18161321.61
Education less than high school, %32343632.87
IVH >3, %233223261.00
PVL, %5683.81
NEC, proven, %20754<.001
Late-onset sepsis, %83745255<.001
BPD, %56413031<.001
Postnatal steroid therapy, %64564330<.001
  • HC indicates head circumference.

  • a Missing data: length growth, 1 infant quartile 1; head circumference growth, 1 infant quartile 1; for quartiles 1 to 4, respectively: length at status: 3, 0, 1, 0; head circumference at status: 2, 0, 1, 0; mother’s education: 5, 11, 5, 7; PVL: 2, 1, 1, 1; BPD: 1, 2, 0,2.

  • b Kruskal-Wallis test for continuous variables; Mantel-Haenszel χ2 or Pearson χ2 for categorical variables, as appropriate.

  • c Status refers to the date/time point that an infant was discharged, transferred, was age 120 days, or reached a body weight of 2000 g.