Attainment of smiling and walking in infancy associates with developmental delays at school entry in moderately-late preterm children: a community-based cohort study

Nienke H Van Dokkum,Arend F Bos,Marlou L A De Kroon,Sijmen A Reijneveld

doi:10.1186/s12887-021-02548-9

Nienke H Van Dokkum, Arend F Bos + Show 2 more

Open Access

https://doi.org/10.1186/s12887-021-02548-9

Copy DOI

Abstract

BackgroundModerately-late preterm (MLP) children (gestational age [GA] 32–36 weeks) are followed-up within community services, which often use developmental milestones as indicators of delay. We aimed to examine associations of parental report of smiling-age and walking-age with developmental delay upon school entry for MLP and full-term children.MethodsThis study regards a community-based cohort study, including 1241 children. Parent-reported smiling-age (n = 514) and walking-age (n = 1210) were recorded in preventive child healthcare. To determine developmental delay at school entry (at age 4) we used the Ages and Stages Questionnaire (ASQ) total and domain scores. We assessed the association of smiling-age and walking-age with dichotomized ASQ-scores, using logistic regression analyses.ResultsFor MLP children, each week later corrected smiling-age was associated with a relative increased likelihood of delays of 31, 43, 36 and 35% in the personal-social, problem-solving, gross motor and general developmental functioning, respectively. Each month later corrected walking-age was associated with a relative increased likelihood of delays of 10, 15 and 13% in the personal-social, gross motor and general developmental functioning, respectively. All corrected smiling-ages and walking-ages were within normal full-term ranges. For full-term children, we only found that later walking-age was associated with delays in the personal-social and gross motor domains.ConclusionsSmiling-age and walking-age are associated with developmental delay in several domains for MLP and full-term children. Professionals could use these milestones to identify children that may benefit from closer monitoring of their development.Trial registrationClinical Trial Registry name and registration number: controlled-trials.com, ISRCTN80622320.

Highlights

10% of all children are born preterm, of which a large majority (80–85%) are moderately-late preterm (MLP, gestational age [Gestational Age (GA)] 32–36 weeks) [1]
Associations of smiling-age and walking-age with developmental delay In Fig. 1 we present the distribution of smiling-age and walking-age for the two GA categories
Using corrected ages for Moderately-late preterm (MLP) children resulted in ages that were within the normal ranges for full-term children

Summary

Introduction

10% of all children are born preterm, of which a large majority (80–85%) are moderately-late preterm (MLP, gestational age [GA] 32–36 weeks) [1]. For full-term children smiling-age has been reported to be associated with cognitive development in later life [9]. Another important milestone is the attainment age of “walking independently” (hereafter: ‘walkingage’) [10,11,12,13]. MLP children have been shown to have a higher frequency of delayed attainment of most milestones using chronological age assessments [16] This delay is attributed to a shorter postconception age at birth as well as altered brain development outside the womb due to perinatal problems, [17, 18] and possibly an earlier influence of the environment [17]. We aimed to examine associations of parental report of smiling-age and walking-age with developmental delay upon school entry for MLP and full-term children

Objectives

Methods

Results

Discussion

Conclusion