Journal of Perinatology (2009) 29, 343–351 r 2009 Nature Publishing Group All rights reserved. 0743-8346/09 $32 www.nature.com/jp
ORIGINAL ARTICLE
Early interventions involving parents to improve neurodevelopmental outcomes of premature infants: a meta-analysis JA Vanderveen1,2, D Bassler3, CMT Robertson4 and H Kirpalani1,5 1
Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada; 2Department of Medicine, University of Ottawa, Ottawa, ON, Canada; 3Department of Neonatology, University Children’s Hospital Tuebingen, Tuebingen, Germany; 4Section of Neurosciences, Department of Pediatrics, University of Alberta, Edmonton, AB, Canada and 5Division of Neonatology, Department of Pediatrics, Children’s Hospital of Philadelphia, PA, USA
Objective: To determine in a systematic review, whether interventions for infant development that involve parents, improve neurodevelopment at 12 months corrected age or older.
Study Design: Randomized trials were identified where an infant intervention was aimed to improve development and involved parents of preterms; and long-term neurodevelopment using standardized tests at 12 months (or longer) was reported. Result: Identified studies (n ¼ 25) used a variety of interventions including parent education, infant stimulation, home visits or individualized developmental care. Meta-analysis at 12 months (N ¼ 2198 infants) found significantly higher mental (N ¼ 2198) and physical (N ¼ 1319) performance scores favoring the intervention group. At 24 months, the mental (N ¼ 1490) performance scores were improved, but physical (N ¼ 1025) performance scores were not statistically significant. The improvement in neurodevelopmental outcome was not sustained at 36 months (N ¼ 961) and 5 years (N ¼ 1017). Conclusion: Positive clinically meaningful effects (>5 points) are seen to an age of 36 months, but are no longer present at 5 years. Journal of Perinatology (2009) 29, 343–351; doi:10.1038/jp.2008.229; published online 15 January 2009 Keywords: preterm infants; low birth weight; early intervention; systematic review
Introduction Although survival among premature infants has improved over the past two decades,1 the long-term morbidity of survivors remains of Correspondence: Dr H Kirpalani, Division of Neonatology, Department of Pediatrics, Children’s Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA 19104, USA. E-Mail:
[email protected] Received 22 June 2008; revised 20 October 2008; accepted 3 December 2008; published online 15 January 2009
serious concern. Follow-up studies of preterm survivors into the school years, consistently find reduced cognitive performance and increased behavioral problems in these children.2,3 Although the etiological pathway of this is uncertain, it is most likely to be of multiple origin. Organic pathology from neonatal sequelae (including bronchopulmonary dysplasia, brain injury and severe retinopathy of prematurity) can predict later neurodevelopmental impairment.4 Environmental factors at any time may also contribute, whether during neonatal intensive care unit (NICU) care,5 subsequent home environment (stemming from maternal age, ethnicity, socioeconomic status),6–9 and parent– infant interactions. Interactions with parents may be compromised for premature infants for several reasons: the emotional response of parents to preterm birth, an altered parental role as a noncaregiver in the nursery, the infant’s characteristics, the NICU environment and the prolonged parent–infant separation.10–19 Early experience can modify the anatomy of the rapidly developing brain,20 which implies that early intervention may alter developmental paths and improve health, educational and social outcomes.21,22 This has prompted the use of early interventions for preterms, aimed at different targets in the complex interplay of biology and environment influencing development. Historically, initial interventions were purely sensory based and focused on providing external stimuli;23 while in contrast, later interventions aimed to minimize the stress of the NICU environment (developmental care). Later still, the recognition of the importance of the caregiving environment was broadened to target interventions including parents. There remains no clear consensus on the efficacy of any of these interventions for preterm children.21,24 A recent review assessed post-discharge early developmental intervention for preterm infants.25 However, this review did not focus on interventions involving parents. This review aims to determine whether early interventions aimed at either teaching parenting skills, and/or involving parents in the hospital care of the preterm, improve either short-term and school-age
Early interventions for premature infants JA Vanderveen et al
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neurodevelopmental outcomes of premature infants. By this definition, developmental care and kangaroo care were included in this review if they clearly stated that the intervention directly involved the parents.
Methods Selection of studies and primary outcomes MEDLINE (1966 to June 2008), EMBASE (1980 to August 2006), CINAHL (1982 to July 2006), PsychINFO (1972 to June 2006) and the Cochrane Central Register of Controlled Trials (Cochrane Library, Issue 2, 2006) were searched using the following MeSH headings: infant, premature; or infant, low birth weight (BW); or neonatal intensive care unit; and early intervention, child development, follow-up studies, parent–child relations, maternal behavior, visitors to patients, family, parenting, family-centered nursing and family-centered care (textword). No language restrictions were applied. All potentially relevant titles and abstracts were retrieved and assessed independently by two observers for eligibility. The reference lists of relevant articles were reviewed, and reference articles were retrieved if these were not obtained by the primary search. In addition, each article was examined for its keywords, which were re-entered into a new search. An expert in neonatal follow-up reviewed the study list for completeness. Studies were selected for inclusion based on the following a priori inclusion criteria; (a) the participants were preterm infants (less than 37 weeks gestational age) or
