Numerous studies in high-risk populations established that variations in infant neuromotor development predict poor cognitive function. It is unclear whether this association is found in the general population. Moreover, previous population-based studies mostly focused on motor milestone achievement.
This study was embedded in the Generation R Study, a population-based cohort in Rotterdam, the Netherlands. Neuromotor development was assessed with an adapted version of Touwen's Neurodevelopmental Examination when infants (1205 males, 1278 females) were on average 12 weeks old (standard deviation 1, range, 9–15 weeks). To measure language function at age 1.5 years, the MacArthur Short Form Vocabulary Checklist was used. At 2.5 years, mothers completed the Language Development Survey and the Parent Report of Children's Abilities measuring language and nonverbal cognitive functioning, respectively.
After adjustment for confounders, less optimal neuromotor development, that is, more low tone symptoms, was associated with a delay in receptive language at 1.5 years (odds ratio [OR], 1.18; 95% confidence interval [CI], 1.05–1.34) and in expressive language at multiple time points (OR, 1.11; 95% CI, 1.02–1.21). Higher scores on overall neuromotor development, indicating a less optimal neuromotor development, was associated with an increased risk of a delay in nonverbal cognitive function at 2.5 years (OR, 1.19; 95% CI, 1.05–1.35).
The results of this study suggest that infants with more low tone symptoms, indicating minor deviances from normal neuromotor development, are somewhat more vulnerable to language delays than those infants who do not have these symptoms.
*The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands;
†Department of Child and Adolescent Psychiatry, Erasmus Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands;
‡Department of Educational Neuroscience, VU Amsterdam, Amsterdam, The Netherlands;
§Institute of Psychology, Erasmus University Rotterdam, Rotterdam, The Netherlands;
‖School of Pedagogical and Educational Sciences, Faculty of Social Sciences, Erasmus University Rotterdam, Rotterdam, The Netherlands;
¶Department of Neonatology, VU Medical Center Amsterdam, Amsterdam, The Netherlands;
**Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands;
††Department of Pediatrics, Erasmus Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands;
§§Department of Psychiatry, Erasmus Medical Center, Rotterdam, The Netherlands.
Address for reprints: Henning Tiemeier, MD, Department of Child and Adolescent Psychiatry, Erasmus Medical Center—Sophia Children's Hospital, P.O. Box 2060, 3000 CB Rotterdam, The Netherlands; e-mail: firstname.lastname@example.org.
The first phase of the Generation R Study is made possible by financial support from the Erasmus Medical Center, Rotterdam, the Erasmus University Rotterdam, and the Netherlands Organization for Health Research and Development (ZonMw No. 10.000.1003). The work of Tamara van Batenburg-Eddes was supported by a grant from the Sophia Children's Hospital Foundation (project number SSWO 443).
Disclosure: The authors declare no conflict of interest.
Received July , 2012
Accepted April , 2013