Global prevalence of long-term neurodevelopmental impairment following extremely preterm birth: a systematic literature review

Abstract

Objective: Neurodevelopmental impairment (NDI) is a major complication of extreme prematurity. This systematic review was conducted to summarize the worldwide long-term prevalence of NDI associated with extreme prematurity.

Methods: Embase and MEDLINE databases were searched for epidemiologic and observational/real-world studies, published in English between 2011 and 2016, reporting long-term prevalence of NDI (occurring from 1 year) among extremely preterm infants born at gestational age (GA) ≤28 weeks.

Results: Of 2406 articles identified through searches, 69 met the protocol NDI definition (24 North America, 25 Europe, 20 Rest of World). Prevalence of any severity NDI in North America was 8%-59% at 18 months to 2 years, and 11%-37% at 2-5 years; prevalence of moderate NDI in Europe was 10%-13% at 18 months to 2 years, 3% at 2-5 years, and 9%-19% at ≥5 years; prevalence of any NDI in Rest of World was 15%-61% at 18 months to 2 years, and 42% at 2-5 years (no North America/Rest of World studies reported any NDI at ≥5 years). A trend toward higher prevalence of NDI with lower GA at birth was observed.

Conclusions: Extreme prematurity has a significant long-term worldwide impact on neurodevelopmental outcomes.

Keywords: Premature birth; developmental disabilities; long-term outcome; neurodevelopment; prevalence; systematic review.

Figure 1.

Study selection process for publications reporting on the prevalence of NDI (PRISMA flowchart). CLD, chronic lung disease; NAm, North America; NDI, neurodevelopmental impairment; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RoW, Rest of World. (A total of 4 articles were identified relevant to CLD; these were excluded from the present SLR as not relevant to NDI).

Figure 2.

Reported prevalence of NDI in included studies by length of follow-up, in (left to right) North America, Europe, and Rest of World. ^aIshii 2013 reports ‘profound’ CP. CP, cerebral palsy; NDI, neurodevelopmental impairment.