ARTICLE
Psychosocial Outcomes of Young Adults Born Very
Low Birth Weight
AUTHORS: Brian A. Darlow, MD, FRACP,a L. John Horwood,
MSc,b Huia M. Pere-Bracken, MA,a and Lianne J.
Woodward, PhDc
aDepartment of Pediatrics, and bChristchurch Health and
Development Study, University of Otago Christchurch,
Christchurch, New Zealand; and cDepartment of Pediatrics and
Psychology, Washington University School of Medicine, St Louis,
Missouri
KEY WORDS
infant, very low birth weight, young adults, long-term outcome,
New Zealand/epidemiology, health status, educational status,
quality of life, questionnaire
ABBREVIATIONS
SGA—small for gestational age
VLBW—very low birth weight
VP—very preterm
Dr Darlow conceptualized and designed the study and drafted
the initial manuscript; Mr Horwood contributed to the study
concept and design, carried out the initial analyses, and
reviewed and revised the manuscript; Ms Pere-Bracken
contributed to the study design, was responsible for all the data
collection, and critically reviewed the manuscript; Dr Woodward
contributed to the study design and reviewed and revised the
manuscript; and all authors approved the final manuscript as
submitted.
www.pediatrics.org/cgi/doi/10.1542/peds.2013-2024
WHAT’S KNOWN ON THIS SUBJECT: Several studies have
suggested that very low birth weight young adults have increased
risks of physical and health problems, educational
underachievement, and poorer social functioning than their
peers, but there are limited population-based and longitudinal
data.
WHAT THIS STUDY ADDS: Former VLBW young adults in this
national cohort scored as well as term controls on many
measures of health and social functioning, including quality-of-life
scores, with some differences largely confined to those with
disability at age 7 to 8 years.
abstract
OBJECTIVE: To assess the early adult health, education, and social
functioning of a national cohort of very low birth weight (VLBW) infants
born in 1986 in New Zealand compared with a control group of young
adults born the same year. The impact of neurodevelopmental disability
at age 7 to 8 years on young adult outcomes was examined.
METHODS: Participants underwent a comprehensive face-to-face interview
that included standardized assessment tools and previously used custom
written survey items.
doi:10.1542/peds.2013-2024
Accepted for publication Sep 19, 2013
Address correspondence to Brian A. Darlow, MD, FRACP,
Department of Pediatrics, University of Otago Christchurch, PO
Box 4345, Christchurch 8140, New Zealand. E-mail: brian.
[email protected]
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2013 by the American Academy of Pediatrics
FINANCIAL DISCLOSURE: The authors have indicated they have
no financial relationships relevant to this article to disclose.
FUNDING: All phases of this study were supported by a project
grant from the New Zealand Child Health Research Foundation
(Cure Kids).
POTENTIAL CONFLICT OF INTEREST: The authors have indicated
they have no potential conflicts of interest to disclose.
RESULTS: We interviewed 230 VLBW young adults (71% of survivors) and
69 controls at age 22 to 23 years. VLBW young adults were 5.6 kg lighter
and 4.2 cm shorter than controls, had lower rates of tertiary education/
training (percentage difference [95% confidence interval]: 213.1 [221.6
to 21.8]) and university degree completion (215.6 [228.0 to 24.8]),
had more often been welfare dependent (23.5 [10.2 to 35.0]), had few or
no friends (20.5 [7.2 to 32.2]), and more often had wheeze in the past
year (20.1 [9.0 to 28.6]). However, in many areas there were no differences between the VLBW cohort and controls, and VLBW adults rated
their overall quality of life and behavioral functioning similarly to their
peers. Those with previous disability had poorer social, occupational,
and physical functioning than other VLBW young adults.
CONCLUSIONS: Despite some evidence of health, educational, and social difficulties, former VLBW young adults obtained similar scores
across many aspects of health and social functioning as their same
age peers, with some differences largely confined to those with previous disability. Pediatrics 2013;132:e1521–e1528
PEDIATRICS Volume 132, Number 6, December 2013
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e1521
Infants born very low birth weight
(VLBW; ,1500 g) or very preterm (VP;
,32 wk gestation) account for 1% to
2% of live births but between 50% and
75% of the workload of NICUs.1 Although survival rates for these infants
now exceed 90%,2 what is most important for the individual, their families, and society is the quality of that
survival in the longer term. Knowledge
of longer term outcomes is also crucial
to inform current neonatal care.
There is now clear evidence demonstrating increased rates of health
problems among surviving VLBW infants
compared with those born at term in
their early years.3 During childhood,
VLBW infants are more likely to experience poor growth, whereas neurosensory impairments, including cerebral
palsy, are seen in up to 10%. Even more
common are neurobehavioral impairments, with up to 40% of school-aged
children born VP experiencing cognitive delay, learning problems, executive
deficits, educational underachievement,
and clinically significant emotional and
behavioral adjustment problems, especially attention-deficit/hyperactivity disorder.4–10 Data are now emerging from
a growing body of cohort and crosssectional studies, particularly during
adolescence but also early adulthood,
showing that these impairments may
persist and in turn impact the preterm
survivor’s longer term functioning and
life-course opportunities.11–17
In 1986, we enrolled all New Zealand VLBW
infants admitted for neonatal intensive
care in a prospective study of retinopathy
of prematurity,18 and surviving children
were followed up at ages 7 to 8 years.8,9
This cohort is unique in being populationbased, characterized by high rates of
antenatal steroid exposure, and with
comprehensive information on child
health and development during middle
childhood. The aim of the current study
was to retrace the cohort at 23 years and
to assess their health, educational and
e1522
occupational achievement, and social
functioning relative to a comparison group
of young adults born at term in the
same year.
METHODS
Participants
The 1986 cohort comprised all 413 VLBW
infants who were live born and admitted
for NICU care in New Zealand, 338 (82%)
of whom survived to discharge.18 At
birth, 58% had received antenatal steroids, 132 (32%) weighed ,1000 g, 126
(31%) were ,28 wk gestation, 103
(25%) were small for gestational age
(SGA), and 95 (23%) were born to
mothers who identified as Maori. Survival for those born ,1000 g and at ,28
wk was 64%. At follow-up at age 7 to 8
years, an additional 12 children had
died, and we assessed 298 children
(96% of survivors who resided in New
Zealand; 91% of all survivors). Of these,
5% had severe disability, 5% had moderate disability, and 15% had mild disability, which was principally an IQ
between 1 and 2 SDs below the mean.8
Compared with the Christchurch Health
and Development Study cohort studied
at the same age, the VLBW cohort had
higher rates of behavioral problems
(conduct disorders, attention problems,
anxiety/withdrawal) and poorer school
achievement.9,19
In the current study, the cohort was
traced through their addresses at age 7
to 8 years, grandparents’ addresses,
general practitioners, National Health
Index codes (a unique person identifier
used within the New Zealand health
system since 1993) via the electoral
rolls and, in a limited number of cases,
by local advertisements. Checks were
made with Statistics New Zealand to see
if any individuals had died since the last
follow-up. A comparison group of individuals who were born at term in New
Zealand and who were not admitted for
NICU care was recruited, initially through
peer nomination by cohort members
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(total of 40) and, because of time constraints, subsequently also via random
sampling from electoral rolls (total of
29), ensuring balance with respect to
the gender, ethnicity, and regional distribution of the sample. There were no
substantive differences between those
recruited by either method in terms of
characteristics or outcome.
Assessment Measures
After written informed consent, all participants underwent a face-to-face interview conducted by 1 researcher,
which lasted ∼2 hours. This interview
examined individual functioning across
a range of domains including the following: current living arrangements;
education, income, and employment;
physical and mental health; family, peer,
and partner relationships; individual
behavior and everyday executive difficulties; and quality of life, self-esteem,
and overall life satisfaction. The interview incorporated a series of standardized assessment tools including
the following: the Short Form 36 Health
Survey, version 2,20 which allows
quality-of-life scores to be derived; the
Behavior Rating Inventory of Executive
Function–Adult Version21; the Barkley
adult self-report scales of attentiondeficit/hyperactivity disorder and oppositional defiant disorder symptoms22;
components of the Composite International
Diagnostic Interview23 for assessment
of mental disorders; the Inventory of
Parent and Peer Attachments24; and the
Rosenberg self-esteem scale.25 This
information was supplemented by
custom written survey items used
previously in the Christchurch Health
and Development Study26 to assess
education, employment, income, health
history, social and partner relationships, and life satisfaction. In addition,
participants were assessed for height,
weight, waist circumference, and body
mass index (BMI). A more detailed description of the measures used in the
ARTICLE
present analysis is provided in Supplemental Table 7.
Statistical Analysis
Between-group comparisons were tested
for statistical significance by using the
x2 test of independence for comparison of percentages, Poisson regression for analysis of count outcomes,
and the t test for independent samples
or analysis of variance for differences
in means of other continuous outcomes. Effect size estimates were
summarized by the mean or percentage difference in outcome between
groups and the associated 95% confidence interval. In supplementary analyses, the VLBW group was further
stratified to test for variation in outcome by previous neurosensory disability at age 7 to 8 (none, mild,
moderate/severe). Analyses were also
conducted to compare outcomes for
those in the VLBW cohort who were
SGA at birth (birth weight ,10th percentile) relative to those who were
normally grown. Finally, to examine
whether effect size differences were
influenced by between-group differences in participant characteristics
(age at assessment, gender, ethnicity,
parental education, socioeconomic status), the observed outcome comparisons were adjusted by using multiple
regression methods (logistic regression for dichotomous outcomes, Poisson regression for count outcomes,
and multiple linear regression for
other continuous outcomes).
The study had 80% power at a = 0.05 to
detect a mean or percentage difference
in outcome between groups with effect
sizes (Cohen’s d) in the range of d = 0.3 to
0.5, depending on the nature of the outcome being assessed. These calculations
suggest the study had adequate power
to detect small to moderate effect sizes.
Where the case group is further stratified (eg, by previous disability), power is
reduced for subgroup analyses. In these
cases, the design has adequate power to
detect moderate to large effect sizes
(d = 0.5–0.8).
The study was approved by the Multiregion Ethics Committee of the Ministry of Health (New Zealand).
RESULTS
Of the national VLBW cohort born in 1986,
324 were believed tobe alivein2008,with
2 known deaths since 7 to 8 years of age
(of unknown causes), and 251 were
traced and approached to take part in
this study. This report concerns the 230
who consented to participate (92% of
those approached; 71% of the surviving
cohort), together with 69 controls.
Table 1 describes the characteristics of
the sample. VLBW participants were
interviewed at a mean age that was 3
months younger than the controls (P ,
.001). There were no significant differences between the proportion of the
230 survivors assessed and the 94
survivors not assessed who weighed
,1000 g at birth; were born at ,28 wk
gestation; were born SGA; were male,
Maori, or Pacific Islander; or who had
moderate/severe disability at 7 to 8
years of age (Supplemental Table 8).
There was no effect of receipt of antenatal steroids related to any of the
outcomes reported below.
Education, employment and income, or
welfare dependence are shown in Table 2.
The VLBW cohort had lower overall educational attainment, with half as many
gaining a university degree. The trend
was most marked for those with previous disability at age 7 to 8 years (34.4%,
no qualifications; 19%, high school completion; 56.9%, tertiary enrollment; 3.4%,
university degree). VLBW graduates were
more likely to have ever been welfare
dependent. There was a clear trend (P ,
.01) on all measures toward lower income, hours worked, and greater welfare dependence with increasing
previous disability at age 7 to 8 years.
(Further information on outcomes for
the VLBW cohort stratified by variation in
previous neurosensory disability at age
7–8 years is provided in the Supplemental Information and Supplemental
Tables 9–13.)
Family, peer, and sexual/partner relationships are shown in Table 3. The VLBW
cohort reported being closer to their
parents/grandparents but had fewer
friends. There were significant trends
for fewer friends and poorer quality
peer relationships as assessed by the
Inventory of Parent and Peer Attachments scale with increasing disability at
age 7 to 8 years (P , .05). In terms of
current living arrangements, the VLBW
cohort was more likely to be still living
TABLE 1 Characteristics of Study Participants
Characteristic
VLBW Cohort
(n = 230)
Term Controls
(n = 69)
Mean/Percentage
Difference (95% CI)
P
Birth weight, mean (SD), g
Male gender, %
Maori/Pacific Island ethnicity, %
Age of mother at birth of
child, mean (SD), y
Mother with tertiary
qualifications, %
Father with tertiary
qualifications, %
Family of professional/
managerial SES, %
Age at assessment,
mean (SD), y
Antenatal steroids, %
1145 (238)
45.2
31.7
26.6 (6.1)
3607 (651)
47.8
23.2
27.8 (4.4)
22462 (22617 to 22307)
22.6 (215.8 to 10.5)
8.6 (24.0 to 19.0)
21.2 (22.8 to 0.4)
,.001
.70
.17
.16
40.8
45.0
24.2 (218.4 to 9.7)
.57
46.4
50.0
23.6 (218.3 to 11.2)
.65
45.1
54.8
29.3 (222.3 to 3.9)
.18
22.4 (0.5)
22.7 (0.7)
20.27 (20.42 to 20.12)
,.001
58.3
—
—
—
CI, confidence interval; SES, socioeconomic status; —, not assessed.
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e1523
TABLE 2 Education, Employment, and Income/Welfare Dependence
Measure
VLBW Cohort Term Controls
(n = 230)
(n = 69)
Educational attainment, %
No formal educational
qualifications
High school completiona
Enrolled in tertiary education/training
Attained a university degree
Employment
Working in paid employment, %
Hours worked per week, mean (SD)
Income/welfare dependence
After-tax income, mean (SD), NZD/wk
Welfare dependent (ever), %
Welfare dependent (past 12 months), %
Mean/Percentage
Difference (95% CI)
P
14.4
5.8
8.6 (20.1 to 14.8)
.06
33.9
73.9
14.8
44.9
87.0
30.4
211.0 (224.1 to 1.8)
213.1 (221.6 to 21.8)
215.6 (228.0 to 24.8)
.10
.024
.003
66.5
25.4 (21.2)
73.9
26.4 (19.9)
27.4 (218.3 to 5.4)
21.0 (26.6 to 4.6)
.25
.73
438 (270)
53.9
31.3
480 (236)
30.4
21.7
242 (2113 to 29)
23.5 (10.2 to 35.0)
9.6 (22.9 to 19.8)
.26
,.001
.13
CI, confidence interval; NZD, New Zealand dollars.
a Completed 5 years of high school education and attained Higher School Certificate, University Entrance or an equivalent
qualification.
TABLE 3 Family, Peer, and Sexual/Partner Relationships
Measure
Family relationships, %
Close/very close relationship
with mother
Close/very close relationship
with father
Close/very close relationship
with grandparents
Peer relationships, %
Has few/no friends
Sexual/partner relationships, %
Had sex (ever)
Had sex (past 12 months)
Had romantic partner
(past 12 months)
Ever cohabited with partner
Ever pregnant/got partner pregnant
Became a parent
VLBW Cohort
(n = 230)
Term Controls
(n = 69)
Mean/Percentage
Difference (95% CI)
P
85.2
88.2
23.0 (210.7 to 7.5)
.53
78.0
63.1
14.9 (2.7 to 28.0)
.014
78.2
61.1
17.1 (3.7 to 31.4)
.011
52.4
31.9
20.5 (7.2 to 32.2)
,.001
76.5
61.7
59.1
89.9
81.2
75.4
213.4 (221.2 to 22.7)
219.5 (229.3 to 27.1)
216.3 (227.0 to 23.4)
.016
.005
.014
50.9
28.7
18.7
59.4
34.8
21.7
28.5 (221.1 to 4.9)
26.1 (219.1 to 5.8)
23.0 (215.0 to 6.8)
.21
.33
.58
CI, confidence interval.
with their parents and less likely to be
rooming with their peers (P , .05; data
not shown). In addition, those with
moderate/severe disability were more
likely to be living with parents (56% vs
36% of those with no/mild disability vs
25% of controls) or in residential care
(22% [5 individuals] vs none in the other
groups) (P , .001). There was an overall
trend toward lesser engagement by the
VLBW cohort in sexual/partner relationships, and rates of engagement
were all substantially lower for those
with moderate/severe disability at age 7
to 8 years (P , .05).
e1524
Substance abuse, criminality, and mental
health are shown in Table 4. The VLBW
cohort had similar rates of tobacco, alcohol, and cannabis use compared with
controls but lesser involvement with
other illicit drugs. There was a consistent trend for those with moderate/
severe disability at age 7 to 8 years to
be much less likely to have any involvement with drugs, both legal and illicit (P , .05). There were no differences
in the rates of Diagnostic and Statistical
Manual of Mental Disorders, 4th edition,
disorders or suicidal behaviors between
the cohort and controls, and there was
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no apparent variability in previous disability.
Physical health and growth variables are
shown in Table 5. As well as an overall
higher incidence of hospital attendance
in the past year and lifetime chronic
illness and wheeze among the VLBW
cohort, there were also higher lifetime
incidences of cardiac (P = .02), vision
(P = .04), and hearing (P = .03) problems
(data not shown). Lifetime hospital
admissions and severe or chronic illness was greatest for those with
moderate/severe disability at age 7 to 8
years. The cohort was, on average, 5.6
kg lighter and 4.2 cm shorter than
controls. The average weight/height
differentials between the cohort and
controls did not vary with gender. There
was also no significant between-group
variability in mean BMI or waist circumference by gender.
Executive functioning, behavior, quality
of life, and overall functioning are shown
in Table 6. The 2 groups had similar
scores on all measures. There was
a trend for poorer behavioral regulation
composite scores (P = .03) on the Behavior Rating Inventory of Executive
Function–Adult Version with increasing
disability at age 7 to 8 years.
Compared with others in the VLBW cohort, those born SGA were, on average,
8.5 (95% CI: 3.2–12.8) kg lighter and 6.3
(95% CI: 3.6–9.0) cm shorter (P , .001).
They were also more likely to have
a lifetime diagnosis of asthma (46.2% vs
30.3%; P = .02) and wheeze in the past 12
months (36.9% vs 29.7%), but this difference was not significant (P = .29).
Finally, analyses were extended by using regression methods to include
control for possible between-group
differences in personal and family
background characteristics (age at
assessment, gender, ethnicity, parental
education, family socioeconomic status). Control for these factors did not
materially affect any of the observed
ARTICLE
TABLE 4 Substance Use, Criminality, and Mental Health
Measure
Substance use, %
Daily smoker
Weekly alcohol use
Cannabis use (ever)
Cannabis use (past 12 months)
Other illicit drug use (ever)
Other illicit drug use
(past 12 months)
Criminality, %
Arrested/convicted (ever)
Mental health, %
Major depression (past 12 months)
Anxiety disorder (ever)
Anxiety disorder (past 12 months)
Suicidal ideation/attempt (ever)
Suicidal ideation/attempt
(past 12 months)
VLBW Cohort
(n = 230)
Term Controls
(n = 69)
Mean/Percentage
Difference (95% CI)
P
28.3
37.4
67.8
30.4
40.4
10.0
26.1
37.7
68.1
36.2
58.0
15.9
2.2 (210.5 to 13.0)
20.3 (213.5 to 12.0)
20.3 (211.9 to 12.0)
25.8 (218.8 to 6.3)
217.6 (230.0 to 24.1)
25.9 (216.8 to 2.2)
.72
.96
.96
.36
.01
.17
18.7
26.1
27.4 (219.7 to 3.1)
.18
20.8
35.2
19.1
27.8
8.7
18.8
37.7
18.8
26.1
8.7
2.0 (29.7 to 11.4)
22.5 (215.7 to 9.8)
0.3 (211.4 to 9.6)
1.7 (210.9 to 12.5)
0.0 (26.4 to 9.5)
.71
.71
.96
.76
1.00
Term Controls
(n = 69)
Mean/Percentage
Difference (95% CI)
P
3.9 (18.1)
2.0 (3.7)
1.9 (20.6 to 4.4)
.07
1.0 (3.2)
0.4 (0.9)
0.54 (0.07 to 1.01)
.015
3.4 (5.2)
2.0 (1.5)
3.7 (5.1)
1.4 (1.3)
20.3 (21.7 to 1.1)
0.54 (0.20 to 0.89)
.59
.005
1.1 (1.2)
0.9 (0.9)
0.22 (20.04 to 0.47)
.12
34.8
13.9
31.7
26.1
11.6
11.6
8.7 (24.1 to 19.6)
2.3 (28.1 to 9.9)
20.1 (9.0 to 28.6)
.18
.62
.018
72.1 (17.0)
166.4 (9.7)
88.7 (14.1)
25.9 (5.7)
77.7 (16.4)
170.6 (10.5)
89.9 (12.9)
26.5 (4.9)
25.6 (210.2 to 21.0)
24.2 (26.9 to 21.5)
21.2 (24.9 to 2.5)
20.6 (22.1 to 0.9)
CI, confidence interval.
TABLE 5 Physical Health and Growth
Measure
Physical health
Lifetime number of hospital
admissions, mean (SD)
Number of hospital attendances
(past 12 months) , mean (SD)
GP visits (past 12 months) , mean (SD)
Lifetime number of severe/chronic
illnesses, mean (SD)
Number of severe/chronic illnesses
(past 12 months), mean (SD)
Asthma (lifetime), %
Asthma (past 12 months), %
Any wheeze (past 12 months), %
Growth, mean (SD)
Weight, kg
Height, cm
Waist circumference, cm
BMI, kg/m2
VLBW Cohort
(n = 230)
.016
,.001
.54
.44
CI, confidence interval; GP, general practice.
differences in outcome between VLBW
and controls.
DISCUSSION
New Zealand VLBW young adults show
clear differences in health, educational
achievement, welfare dependency, and
social engagement compared with controls. VLBW young adults were, on average, 5.6 kg lighter and 4.2 cm shorter
than controls. The VLBW young adults
less often had a university degree and
were more likely to have either no
qualifications or high school qualifications only. They were less likely to be
living independently. Approximately onequarter of the VLBW cohort and controls
were daily smokers, and one-third of
both groups used alcohol weekly and
had used cannabis in the past year, but
fewer VLBW graduates had ever used
other illicit drugs or been arrested. In
addition, they had a higher lifetime
number of severe or chronic illnesses
and were almost 3 times more likely to
have been admitted to a hospital in the
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past year. However, in many areas, there
were no differences between the VLBW
young adults and controls, and VLBW
graduates rated their overall quality of
life and behavioral functioning in a similar way to their term peers.
Several reports have shown that former
VLBW/VP young adults do have lower
median IQ scores than their peers, even
after excluding those with neurosensory
impairments and controlling for confounding factors; and fewer graduate
from high school or enter tertiary education.11,12,27 We did not formally measure IQ in this study, but differences in
educational outcomes between the
VLBW young adults and controls were
more marked in those with previous
disability at 7 to 8 years. Similarly, there
were clear trends for those with previous disability, and particularly those
with moderate or severe disability at
age 7 to 8, to have poorer social, occupational, and physical functioning, and
to exhibit poorer behavioral regulation
than other VLBW young adults.
There are a number of studies that have
reported respiratory outcomes in former VLBW/VP late-adolescents,12,28,29 although few in young adults.30–33 In
general, the evidence suggests that
VLBW/VP survivors, particularly if they
had chronic neonatal lung disease, have
reduced forced expiratory volume in 1
second, lower forced vital capacity, and
decreased diffusing capacity. In our cohort at 7 to 8 years of age, we found that
32% had a diagnosis of asthma at the
time of follow-up, with a significant
trend (P , .05) of greater risk of
asthma with decreasing gestation.34 At
23 years the VLBW young adults were
almost 3 times more likely than the
controls to have experienced wheeze in
the past 12 months (32% vs 12%; P =
.02), with a greater proportion having
a lifetime diagnosis of asthma, although
this difference was now not significant.
An important finding for the VLBW young
adults themselves was that relative to
e1525
TABLE 6 Executive Functioning, Behavior, Quality of Life, and Overall Functioning
Measure
BRIEF-A index, mean (SD)
Behavioral regulation index T score
Metacognition index T score
Global executive composite T score
ADHD/ODD symptoms, mean (SD)
ADHD score
ODD score
SF-36 component scores (relative
to 18–24-year norms), %
.1 SD below mean, physical
component score
.1 SD below mean, mental
component score
Overall functioning, mean (SD)
Self-esteem
Life satisfaction
VLBW Cohort
(n = 230)
Term Controls
(n = 69)
Mean/Percentage
Difference (95% CI)
P
52.9 (12.5)
51.0 (10.5)
52.0 (11.4)
51.7 (9.3)
50.1 (8.0)
50.8 (8.2)
1.2 (22.0 to 4.4)
0.9 (21.8 to 3.6)
1.2 (21.7 to 4.1)
.45
.49
.40
8.4 (6.7)
3.1 (3.2)
7.8 (5.3)
2.7 (2.8)
0.6 (21.1 to 2.3)
0.4 (20.4 to 1.2)
.55
.45
15.7
13.2
2.5 (28.1 to 10.6)
.62
6.5
4.4
2.1 (25.9 to 7.1)
.52
20.1 (21.5 to 1.3)
20.5 (21.9 to 0.9)
.88
.52
31.7 (5.1)
41.6 (5.2)
31.8 (4.6)
42.1 (5.1)
ADHD, attention-deficit/hyperactivity disorder; BRIEF-A, Behavior Rating Inventory of Executive Function–Adult Version; ODD,
oppositional defiant disorder; SF-36, Short Form 36 Health Survey, version 2.
their term peers, there were no significant differences on the Short Form 36
physical or mental component scores or
on measures of perceived overall functioning, self-esteem, or life satisfaction.
Similar findings have been reported
previously for self-reported quality-of-life
scores, even when scores obtained from
parents or other observers have been
lower than those for controls.16,35–39
Our report is the first, to our knowledge,
from New Zealand to document outcomes
for former VLBW infants in young adulthood. Those of Maori descent, the indigenous population in New Zealand,
were overrepresented in the cohort with
23% of mothers recording Maori ethnicity
compared with 13% of all births in 1986.
At follow-up, 26.5% of the cohort identified
themselves as Maori and 5.7% as of Pacific Island descent. Overall, consistent
with national data, Maori participants
had poorer educational qualifications,
higher welfare dependence, higher suicidal ideation/attempt, arrest/conviction,
cannabis use, daily smoking, higher rates
of pregnancy/parenthood, and higher
BMI scores. However the number of
Maori participants in the control group
was too small to draw useful conclusions
regarding the size of VLBW/control differences for Maori and non-Maori participants.
e1526
Strengths of our study include that it is
a national cohort, more than half of
whom received antenatal steroids, and
that an assessment had been made in
middle childhood. Data from other
countries are now revealing a range of
functional and health-related challenges faced by former VLBW infants in
late adolescence and early adulthood.11,12
However, most cohorts were born in the
1970s or early 1980s when few infants
received antenatal steroids and so may
be less representative of modern neonatal intensive care than our study.
Whereas antenatal steroids reduce
mortality by ∼40%,40 it is interesting
that in this study receipt of antenatal
steroids had no effect on any long-term
outcomes. In addition, in New Zealand
few infants of #23 wk gestation were
offered NICU care in 1986, which largely
remains the case with contemporary
care. Many studies in other countries
have been hospital based and so may
be subject to a degree of bias. Of the
few population-based studies, most
are regional or rely on constrained
national registry data.41–44 The study
that is most similar to ours is the
Netherlands Project on Preterm and
Small for Gestational Age Infants study in
VLBW/VP infants born in 1983.45,46 As in
our study, Hille et al,46 reporting from the
DARLOW et al
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POPS study cohort at age 19 years, found
that VLBW survivors had greater difficulty establishing social contacts but did
not have elevated risks of psychopathology compared with their term-born
peers.
A limitation of our study is that we
assessed both the VLBW cohort and
controls by face-to-face interview only.
Our follow-up included 71% of those
known to be alive at 23 years. Young
adulthood is a time of high mobility, and
many members of our cohort are
known to be overseas, such trips still
being a “right of passage” for many
young New Zealanders. There were,
however, no differences in the basic
demographic characteristics of those
who did and did not participate in our
study. Our follow-up rate is comparable
to that reported in most international
studies. For example, in the highly informative Helsinki Study32,47–49 there
were 474 consecutive VLBW admissions
to the regional NICU from January 1978
to December 1985; 335 were discharged alive, 95% survivors were
traced, 255 residing in the Helsinki
area were invited to participate, and
166 did so (50% overall). The Netherlands
POPS study at 19 years achieved 62%
follow-up,45 and studies of pulmonary
function in late adolescence in VP
infants from Melbourne, Australia, included 74% of survivors.29
Despite the relatively positive findings,
it will be important to objectively assess
health and neuropsychological functioning in the cohort, and we are currently undertaking a battery of medical
and neuropsychological investigations
at age 26 to 27 years. Knowledge of the
range of health issues faced by VLBW
young adults will inform future neonatal
care in general and in New Zealand and
will guide multidisciplinary intervention
and provision of medical care and social
support in childhood and adolescence.
ARTICLE
CONCLUSIONS
We have shown that, whereas New
Zealand VLBW young adults do experience
lower levels of educational achievement
and greater social isolation, there are no
differences on many measures of health
and social functioning, and the young
people themselves report similar overall
life functioning and quality of life to their
same age peers.
ACKNOWLEDGMENTS
We thank Mrs Nina Mogridge and Mrs
Nicki McNeill for assistance in tracing
the cohort. We also thank the young
adults who participated in the study.
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Psychosocial Outcomes of Young Adults Born Very Low Birth Weight
Brian A. Darlow, L. John Horwood, Huia M. Pere-Bracken and Lianne J. Woodward
Pediatrics; originally published online November 18, 2013;
DOI: 10.1542/peds.2013-2024
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PEDIATRICS is the official journal of the American Academy of Pediatrics. A monthly
publication, it has been published continuously since 1948. PEDIATRICS is owned, published,
and trademarked by the American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk
Grove Village, Illinois, 60007. Copyright © 2013 by the American Academy of Pediatrics. All
rights reserved. Print ISSN: 0031-4005. Online ISSN: 1098-4275.
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Psychosocial Outcomes of Young Adults Born Very Low Birth Weight
Brian A. Darlow, L. John Horwood, Huia M. Pere-Bracken and Lianne J. Woodward
Pediatrics; originally published online November 18, 2013;
DOI: 10.1542/peds.2013-2024
The online version of this article, along with updated information and services, is
located on the World Wide Web at:
/content/early/2013/11/12/peds.2013-2024
PEDIATRICS is the official journal of the American Academy of Pediatrics. A monthly
publication, it has been published continuously since 1948. PEDIATRICS is owned,
published, and trademarked by the American Academy of Pediatrics, 141 Northwest Point
Boulevard, Elk Grove Village, Illinois, 60007. Copyright © 2013 by the American Academy
of Pediatrics. All rights reserved. Print ISSN: 0031-4005. Online ISSN: 1098-4275.
Downloaded from by guest on June 17, 2017