Latent class growth analysis identified different trajectories in cognitive development of extremely low birthweight children

Anu Haavisto; Liisa Klenberg; Viena Tommiska; Aulikki Lano; Kaija Mikkola; Vineta Fellman; Finnish ELBW Cohort Study Group (FinELBW)

doi:10.1136/bmjpo-2021-001361

Latent class growth analysis identified different trajectories in cognitive development of extremely low birthweight children

BMJ Paediatr Open. 2022 Apr;6(1):e001361. doi: 10.1136/bmjpo-2021-001361.

Authors

Anu Haavisto^{1

2}, Liisa Klenberg³, Viena Tommiska⁴, Aulikki Lano⁵, Kaija Mikkola⁴, Vineta Fellman^{5

6

7}; Finnish ELBW Cohort Study Group (FinELBW)

Collaborators

Finnish ELBW Cohort Study Group (FinELBW):
Annika Koivisto, Marit Korkman, Liisa Lehtonen, Tuija Löppönen, Päivi Olsén, Outi Tammela

Affiliations

¹ Department of Psychology and Logopedics, University of Helsinki, Helsinki, Finland anu.haavisto@helsinki.fi.
² Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
³ Niilo Mäki Institute, Jyväskylä, Finland.
⁴ New Children's Hospital, Pediatric Research Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
⁵ Children's Hospital, University of Helsinki, Helsinki, Finland.
⁶ Department of Clinical Sciences, Pediatrics, Lund University, Lund, Sweden.
⁷ Folkhälsan Research Center, Helsinki, Finland.

Abstract

Background: Recent longitudinal studies suggest stable cognitive development in preterm children, although with great individual variation. This prospective neurocognitive follow-up study of extremely low birthweight (ELBW, <1000 g) children aimed to characterise groups with different developmental trajectories from preschool to preteen age.

Methods: ELBW children (n=115) born in Finland in 1996-1997 participated in cognitive assessments at a median age of 5.0 years and 11.3 years. A standardised test of intelligence (Wechsler Preschool and Primary Scale of Intelligence-Revised or Wechsler Intelligence Scale for Children-third edition) was administered at both ages.

Results: Three ELBW groups with different developmental trajectories over time were identified with latent class growth analysis. Children with average (Full-Scale IQ (FSIQ): 85-115) and below average (FSIQ: <85) intelligence at 5 years of age had significant decreases in intelligence scores by 11 years of age (-11.7 points and -14.9 points, respectively, both p<0.001), while those with above average intelligence (FSIQ: >115) showed stable development (-3.2 points, p=0.250). Multiple linear regression showed that neonatal complications (intraventricular haemorrhage grade 3-4 and blood culture positive sepsis) and maternal education significantly predicted lower intelligence at the second assessment (F(3,106)=7.27, p<0.001, adjusted R²=0.147).

Conclusions: ELBW children represent a heterogeneous patient population in which groups with different cognitive trajectories can be detected. Deterioration may occur particularly in children with initial average or below average cognitive performance at 5 years of age, with neonatal complications and lower maternal education presenting as risk factors. Catch-up in cognitive functions seems more uncommon in the ELBW population, which should be noted in clinical work.

Keywords: Neonatology; Neurology; Psychology.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Child
Child, Preschool
Cognition
Follow-Up Studies
Humans
Infant, Extremely Low Birth Weight*
Infant, Newborn
Intelligence*
Prospective Studies