Weight Status in the First 2 Years of Life and Neurodevelopmental Impairment in Extremely Low Gestational Age Newborns

Abstract

Objective To examine the extent to which weight gain and weight status in the first 2 years of life relate to the risk of neurodevelopmental impairment in extremely preterm infants. Study Design In a cohort of 1070 infants born between 23 and 27 weeks’ gestation, we examined weight gain from 7-28 days of life (in quartiles) and weight z-score at 12 and 24 months corrected age (in categories: <−2; ≥−2, <−1; ≥1, <1; ≥1) in relation to these adverse neurodevelopmental outcomes: Bayley-II mental development index <55, Bayley-II psychomotor development index <55, cerebral palsy, Gross Motor Function Classification System (GMFCS) ≥1 (cannot walk without assistance), microcephaly. We adjusted for confounders in logistic regression, stratified by sex, and performed separate analyses including the entire sample, and excluding children unable to walk without assistance (motor impairment). Results Weight gain in the lowest quartile from 7-28 days was not associated with higher risk of adverse outcomes. Children with a 12-month weight z-score <−2 were at increased risk for all adverse outcomes in girls, and for microcephaly and GMFCS ≥1 in boys. However, excluding children with motor impairment attenuated all associations except that of weight z-score <−2 with microcephaly in girls. Similarly, most associations of low weight z-score at 24 months with adverse outcomes were attenuated with exclusion of children with motor impairment. Conclusion Excluding children who have gross motor impairment appears to eliminate the association of low weight status with neurodevelopmental impairments at 2 years in extremely preterm infants.

Two-Year Follow-Up Outcomes of Premature Infants Enrolled in the Phase I Trial of Mesenchymal Stem Cells Transplantation for Bronchopulmonary Dysplasia

“…Further studies will be necessary to clarify the associations of later weight gain with better long-term neurodevelopmental outcomes. 27 BPD has been identified as an independent risk factor for the development of long-term neurodevelopmental impairments, including cerebral palsy and developmental delays, even in the absence of catastrophic brain injury. [28][29][30] In preclinical studies in newborn rats, 31 the intratracheal transplantation of MSCs simultaneously attenuated both hyperoxic lung and brain injuries, and the extent of neuroprotection was closely linked with that of pulmo-protection.…”

Should the Gross Motor Function Classification System be used for children who do not have cerebral palsy?

“…Among the 118 papers, 76 did not mention that the GMFCS was developed specifically for use with children with CP or discuss its measurement properties . Twenty noted that the GMFCS was created for children with CP but did not justify its application to their condition/clinical description .…”

“…In 38 studies, the five GMFCS levels were collapsed into two or three broader groups (e.g. levels I, II, and III combined under the title of ‘ambulatory’ participants and levels IV and V combined under the title of ‘non‐ambulatory’ participants) . In one study involving children with CP, closed‐head injury, learning disability, or developmental delay, merging of levels (i.e.…”

“…This was to accommodate a lack of spontaneous running or jumping in people with visual deficits. Another study described GMFCS level I as representing ‘normal’ mobility, while 15 studies used a GMFCS level of less than I or GMFCS level ‘0’ to reflect ‘normal’ development or no gross motor dysfunction. One retrospective study used a ‘possible level I’ when they could not decide between ‘level 0’ and level I …”

Biases Inherent in Studies of Coffee Consumption in Early Pregnancy and the Risks of Subsequent Events

“…This is an example of "reverse causation," which refers to situations where an antecedent is a consequence rather than a cause of illness. [51,[112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127][128][129] Another example has occurred in some studies that have found that people whose weight (or body mass index) is low were at heightened risk of death. [130] Low weight can be a consequence of disease that results in a loss of appetite.…”