Objective. To examine the health status, functioning, and special health care needs of children 10 to 14 years old weighing <750 g at birth.
Methods. We compared outcomes of a regional cohort of 59 children born from 1982 through 1986 weighing <750 g at birth (mean: 665 g; gestational age: 26 weeks) to matched groups of 54 children weighing 750 to 1499 g at birth and 49 children born at term. Assessments of limitations in functioning, compensatory dependence and needs for services above routine, at a mean age of 11 years, were based on responses to maternal questionnaires. Rates of these outcomes were compared between groups using logistic regression analyses that controlled for gender and social risk.
Results. Children weighing <750 g at birth had significantly higher rates of functional limitations, greater compensatory dependence, and need for services above routine than the other 2 groups. Compared with children born at term, the odds ratio for mental or emotional delay was 4.7 (95% confidence interval [CI]: 2.0–11.0), for restrictions in activity, 5.1 (CI: 1.6–16.3) and for blindness or difficulty seeing 3.9 (CI:1.3–11.4). With the exception of 3% of children who were severely impaired, the only compensatory aid that differentiated the children weighing <750 g at birth from the children born at term was the greater need for glasses (odds ratio [OR]: 2.8 [CI: 1.3–6.3]). Increased services above routine included special education (OR: 5.0 [CI: 2.1–11.7]), counseling (OR: 4.8 [CI: 1.0–23.1]) and special arrangements in school (OR: 9.5 [C.I. 2.1–43.6]).
Conclusion. Parents and educators need to be informed of the potential for disability and special health care needs of children weighing <750 g at birth.
The potential for survival of extremely low birth weight infants (<750 g) has increased in the 1990s.1 The school age outcomes of this population have been well-described and include high rates of cognitive and neurosensory impairment, as well as learning and behavioral difficulties even among children without severe impairments.2–7 However, the overall rates of disability resulting from health problems and educational difficulties, and the associated special health care needs of this population of children have not been reported. During the 1990s approximately 10 000 live born infants weighing <750 g at birth were delivered annually in the United States, of whom 50% or more survived to early childhood.1,8,9 The federal mandate for individual states to provide services for children with special health care needs necessitates examination of this aspect of extremely low birth weight survival.10
Children with special health care needs are defined as those who have, or are at increased risk for a chronic physical, developmental, behavioral, or emotional condition and who also require health and related services of a type or amount beyond that required for children generally.11 Extremely low birth weight children are, by virtue of their biologic risk, included in the category of children at risk for special health care needs.
As part of an ongoing longitudinal study of extremely low birth weight outcomes, we sought to examine general health status and rates of disability and special health care needs of a regional cohort of children born weighing <750 g at 10 to 14 years of age.12,13 We hypothesized that children weighing <750 g at birth would have significantly more functional limitations, need more compensatory accommodations, and require more services beyond routine care as compared with children weighing between 750 and 1499 g at birth and controls born at term.
POPULATION AND METHODS
The study participants included the survivors of a regional cohort of 243 children weighing <750 g at birth who were born from 1982 through 1986 in the greater Cleveland area. Seventy-three (30%) children survived to discharge home. At early school age (mean age: 7 years), 68 (93%) of the survivors were studied. Their outcomes were compared with 2 comparison groups, a group of children born weighing between 750 and 1499 g and a group born at full term.12 For each child weighing <750 g, we selected the next survivor who was born weighing between 750 and 1499 g treated at the same perinatal center and of the same race and sex. Three children were not tested because of missed appointments. Thus the initial comparison group with birth weights between 750 and 1499 g included 65 children. The comparison group, born at term gestation, was formed by randomly selecting a full-term child from the same classroom as the child born weighing <750 g who was of the same sex, race, and birth date within 3 months. Matches could not be selected for 7 children. Thus the original term born control group included 61 children.
The present study was performed at middle school age, 4 years after the initial study. At this time, 60 children weighing <750 g at birth, 55 children weighing between 750 and 1499 g at birth, and 49 children born at term were available for study. Reasons for exclusion from the study included the following: moving out of the region (4 children), inability to locate (7 children), and lack of follow-through (19 children). One child weighing <750 g and 1 child weighing between 750 and 1499 g at birth had incomplete maternal questionnaire data. The present study thus included 59 children who weighed <750 g at birth, 54 children who weighed between 750 and 1499 g at birth, and 49 controls born at term. These children constitute 88%, 85%, and 80%, respectively of those who participated in the early school age study. The 59 children weighing <750 g at birth comprise 81% of their birth cohort.
Table 1 presents the maternal demographic risk factors and child descriptors of the children weighing <750 g at birth, children weighing between 750 and 1499 g at birth, and term gestation at a mean age of 11 years (range: 10–14 years). The group weighing <750 g at birth was of significantly lower birth weight and gestational age by study design. Significantly more of these children were small for gestational age (SGA) resulting from intrauterine growth failure. Sixty-eight percent of the sample was female because of the greater survival of girls in the group born weighing <750 g. Nine children (15%) weighing <750 g at birth had major neurosensory abnormality including 5 with cerebral palsy, 1 of whom was also blind. Three additional children had unilateral or bilateral blindness and 1 was deaf. Within the <750-g birth weight group of children, the 26 SGA children had similar rates of neurosensory abnormality compared with those born appropriate for gestational age (3 [12%] vs 6 [18%]). Three children (6%) weighing between 750 and 1499 g at birth had cerebral palsy, 1 of whom was unilaterally deaf. The mothers of the children weighing <750 g at birth, compared with those of children weighing between 750 and 1499 at birth had a lower social risk index. This index includes maternal race (with scores of 0 for white and 1 for black), current maternal education (0 for high school or above and 1 for less than high school education), and marital status (0 for married and 1 for unmarried).12 The composite scale ranges from 0 for lowest social risk to 3 for highest social risk. Four children (7%) weighing <750 g at birth and 2 children (4%) weighing between 750 and 1499 g at birth were adopted, and 2 (3%) and 1 (2%), respectively, were in foster care.
The 59 children weighing <750 g at birth, when compared with the 14 children lost to follow-up did not differ significantly in birth weight or gestational age. When compared with the 9 children who participated in the early school age study but were not included in this investigation, the 59 children studied had a lower mean birth weight (665 ± 69 g vs 704 ± 29 g; P < .01) but did not differ significantly in gestational age, intrauterine growth, maternal education or marital status, race, sex, or neurocognitive status at early school age.
As part of an overall assessment of health, growth, functioning and neuropsychologic performance, the parent was interviewed and the child tested during a single half-day session. The measures of neuropsychologic and psychosocial functioning have been described.14 Two additional questionnaires, the Family and Health Questionnaire and the Report of the Child's Educational Progress, were administered to the parent. The Family and Health Questionnaire included sociodemographic information and questions from the Physical Health Scale of the Rand Health Insurance Study and from the 1988 Child Health Supplement of the National Health Interview Survey.15,16 The Report of the Child's Educational Progress included questions with regard to special help and adjustments in school and whether the child had an Individual Educational Plan. Additional questions pertained to involvement in counseling or psychotherapy, social skills training, behavior modification, speech therapy, occupational or physical therapy or any other types of help the child was receiving.
We used the noncategorical or generic approach, which uses consequence-based criteria, rather than symptoms or diagnoses of specific conditions or diseases.17–19 For this purpose responses to the questionnaires were categorized according to the items listed in the Questionnaire for Identifying Children With Chronic Conditions (QuICCC) developed by Stein.19,20 Although we used the algorithm of the QuICCC, we examined overall functioning and special health care needs rather than those related specifically to chronic conditions. Limitation in functioning was assessed by items pertaining to activity restrictions, inability to play with other children, difficulty feeding, dressing, washing or toileting, and difficulty hearing, seeing, or communicating. Compensatory dependency was assessed by questions on medication use, special diet, and use of special equipment or personal assistance. Service use beyond routine included doctor visits, nursing care or treatment, physical or speech therapy, psychological services and the need for special arrangements at school.19,20 The individual items pertained to the previous 12 months, with the exception of growth delay that pertained to whether the child had ever had this problem. Of the functional limitations, a learning problem was coded as mental delay. An emotional or behavioral problem was coded as emotional delay. Impaired socialization was coded if the parent noted on the Child Behavior Checklist that the child got along worse with other children compared with children of the same age.21 The majority of items from the QuICCC were considered, with the exception of 3 of 15 items in the domain of “Functional Limitation” and 3 of 12 items in the domain of “Service Use Above Routine” that were not applicable or addressed in our population.20
χ2 analysis was used to compare the 3 groups of children with regard to outcomes at middle school age. Overall differences on continuous measures were examined by analysis of variance. The <750-g birth weight group was also compared with each of the 2 comparison groups using logistic regression with gender and social risk index included as covariates. The α level for significance was P < .05.
Functional Limitations (Table 2)
The children weighing <750 g at birth, when compared with the children born at term, had significantly higher rates of physical growth delay, mental or emotional delay, restriction in activity, inability to participate in sports or physical activities and blindness or difficulty seeing. The 2 groups of very low birth weight children had similar high rates of mental or emotional delay and deafness or difficulty with hearing but differed significantly with regard to growth delay and visual difficulty. The most severe functional limitations, such as difficulty with feeding, washing and using the toilet, were restricted to children with severe neurosensory deficits, including 2 children weighing <750 g at birth and 1 child weighing between 750 and 1499 g at birth. The mean number of functional limitations per child (2.4 ± 2, 1.6 ± 2, and .7 ± 1 for the 3 groups, respectively) were significantly different (P = .000).
Compensatory Dependence (Table 3)
Children weighing <750 g at birth had a significantly greater need for glasses in comparison to children born weighing between 750 and 1499 g at birth and to children born at term. The need for special equipment or help for walking, feeding, dressing, washing or toileting was restricted to the 3 neurologically abnormal children who had severe functional limitations. The mean number of compensatory needs per child (1.2 ± 1 standard deviation, .6 ± 1 and 0.6 ± 0.6, respectively) were significantly different (P = .009).
Service Use Above Routine (Table 4)
The children weighing <750 g at birth when compared with the children born at term had a significantly greater need for services above routine, including going to a counselor, psychologist, or social worker, receiving physical or occupational therapy, and requiring separate or special class instruction, special arrangements in school or an Individualized Educational Plan (IEP). The children weighing <750 g at birth when compared with children weighing between 750 and 1499 g at birth had significantly higher rates of physical or occupational therapy use, separate or special class instruction, special arrangements in school, and an IEP. The mean number of services received per child (2.1 ± 2, 1.1 ± 1, and .7 ± 1, respectively) were significantly different (P = .000).
The differences between groups on all measures of functional limitations, compensatory dependence and services above routine were similar when adjusted for gender and social disadvantage (see Tables 2,3, and 4). In these analyses social risk was significantly related to only 4 outcomes (mental or emotional delay, any compensatory dependence, separate or special class instruction, and having an IEP).
Rates of Problems in Multiple Domains
Thirty-one (53%) children born weighing <750 g were identified in all 3 domains (functional limitations, compensatory dependence, and needs for services above routine), compared with 12 (22%) of the children born weighing between 750 and 1499 g and 7 (14%) of the children born at term. Only 3 (5%), 11 (20%), and 9 (18%) children in these 3 groups respectively were free of any functional limitations, need for aids or special health care needs, as defined in this study.
Chronic conditions, which included asthma, arthritis, cerebral palsy, seizures, and chronic constipation occurred in 41%, 30% and 8% of the 3 groups, respectively. Chronic constipation was the only condition that occurred significantly more often among the children born weighing <750 g compared with each of the other 2 groups (Table 5). This occurred mainly among children with neurologic impairment or subnormal cognition. When chronic constipation was excluded, the rates of chronic conditions decreased to 25%, 28%, and 8%, respectively. The mean number of physician visits per year were 3.1 ± 3, 2.5 ± 2, and 2.9 ± 3 for the 3 groups, respectively, and were in part for follow-up treatment of various accidents and injuries. Six (10%), 7 (13%), and 2 (4%) of the 3 groups, respectively, reported accidents during the previous year.
This is the first report of the impact of extremely low birth weight on childhood health, defined broadly as the ability to participate fully in developmentally appropriate physical, psychological and social tasks, and on the need for special aids and services at school age. We used the noncategorical or generic approach, which focuses on the consequences of various diverse medical, behavioral, and cognitive disorders rather than using diagnostic labels. This method has been suggested as the best means for the identification and planning of federal aid and services for children with special health care needs.11,18,19 Additional strengths of this study are the regional composition of the cohort, the excellent return rate, and inclusion of matched comparison groups of children.
The results of this study of extremely low birth weight children at middle school age confirm our hypothesis of high rates of functional limitations and special health care needs for these children. Major functional limitations include physical growth and mental or emotional deficiencies, restriction in physical activities, inability to participate in sports, and visual difficulties. With the exception of a very small percentage (3%) of children with severe neurologic impairments who needed extra help, the only compensatory aid that differentiates children weighing <750 g at birth from others is the need to wear glasses. They do, however, have an excessive need for services above routine, mainly for special education, counseling, and occupational and physical therapy. For most outcomes there is a birth weight gradation with the highest rates of functional disability and special health care needs found in children weighing <750 g at birth and the lowest rates for children born at term. Exceptions to this trend are chronic medical conditions that did not distinguish the <750-g and the 750- to 1499-g birth weight groups and overall rates of recurrent and chronic medical conditions, doctor visits, medication usage, and accidents that were similar across all 3 groups of children.
Prevalence rates of health and functioning are dependent on the population studied, method of collection, definitions used, and consideration of duration and severity of conditions.22,23Higher rates of disability, chronic illness, and special health care needs are reported with increasing age during childhood and among children of single parents and poor families.20,24 The relatively high prevalence of social disadvantage in our study population compared with the national cohort may partly account for our high rates of functional disability and health care needs.25 Furthermore, because of the difficulty in ascribing functioning and needs to certain conditions, in contrast to the QuICCC, we considered the child's overall functioning and special health care needs rather than specifically examining disability and health care needs resulting from chronic conditions. We also expanded the scope of certain items included in the QuICCC.19 For example, all children who required corrective vision were included rather than only those who did not achieve functional vision with glasses. In fact when corrected with glasses, only 8 children who weighed <750 g at birth did not have vision of 40/200 or better. We also added the item “Excessive Visits to Doctors” to the services above routine domain. Furthermore, the interviews were administered by research assistants who knew the families from the early school age study, at which time a comprehensive medical and neuropsychologic assessment had been performed and the parents informed of these results.12 The children weighing <750 g at birth and those children weighing between 750 and 1499 g at birth had also had repeated assessments during early childhood and many were receiving help in school. These experiences may have increased the parents' knowledge of their childrens' problems and influenced their responses. Our results, which represent a synthesis of the parent's perceptions of the child's health and information received from objective assessments, probably represent the true state of the child's overall functioning and health care needs.22,23
With the exception of chronic constipation, our overall rates of chronic illness, accidents, physician visits and medication usage, and special education for the groups of children weighing <750 g at birth and those weighing between 750 and 1499 g at birth are in agreement with reports of children weighing <1000 g at birth.26–32 McCormick et al26 reported that only 22% of children weighing <1000 g at birth were without a specified condition and/or limitation in activity of daily living at 8 years of age. Our rates of chronic and recurrent medical conditions, behavior problems requiring psychological help, and physician utilization among the term born cohort are also similar to North American, Canadian, and British reports.22,33–38
Childhood chronic illness and disability has increased nationally resulting from improved survival of preterm infants and infants with congenital malformations, as well as increased survival of children with cancer and the enhanced identification of children with disabilities.24 The improved survival of children weighing <750 g at birth in the 1990s has resulted from improvements in neonatal intensive care including introduction of surfactant therapy and increased use of respiratory support.39 But the rates of neonatal and early childhood morbidity of children born weighing <750 g have not changed, despite the improved survival.1,9,40,41 We thus predict that current survivors will have functional limitations and health care needs similar to those described in this study.1,39,40 However, because children born weighing <750 g constitute only .3% of all live births, they will represent a very small fraction of all children with special health care needs nationally. Furthermore, although their needs for special educational arrangements in school are high, very few children have severe impairments that curtail major activities of daily living, such as eating, bathing and dressing, and prevent school attendance. Recent reports by Saigal42 and others43indicate an acceptable quality of life for the majority of adolescent and young adult preterm children, even for those with disabilities.
The reality that the majority of infants born at or above 24 weeks gestation and/or weighing 600 g at birth are currently surviving necessitates a renewed consideration of the causes of the enormous morbidity and the implications for their school age and later educational needs. The relative lack of effect of social risk on the functional outcomes and special health care needs described in this article are in agreement with our previous findings that neonatal risk factors have a greater effect on neuropsychologic outcomes than social risk factors.13 McCormick et al26 similarly found no relationship between maternal education and the health status or IQ of children weighing <1000 g at birth. Research into therapies to prevent or treat neonatal complications of prematurity, rather than early intervention strategies after discharge, will thus probably have the greatest impact on improving the future outcomes of this extremely high-risk population of children.44
Stevenson estimated that for British children weighing <2000 g at birth, of whom 7.7% were disabled, special education for the disabled children accounted for 52% of their total expenditure to age 8 to 9 years and neonatal care for only 35%.45 Such data are unavailable in the United States.46 Federal law mandates that states provide services for children with special health care needs but usually only for those with severe disability and family income restrictions. Thus many families are burdened with excessive expenses to cover special medical and educational costs. The results of this study indicate that both parents and educational providers need to be informed of the potential for functional disability among extremely low birth weight children and to plan for their special health care needs. Furthermore, ongoing assessment and support with proactive programs need to be provided from infancy and into the school years.
This work was supported by Grant HD 26554 from the National Institutes of Child Health and Human Development.
We thank Drs Ruth E. K. Stein, Dennis Drotar, and Avroy A. Fanaroff for their critical review of the manuscript; Kathy Winter, Anne Birnbaum, Diane Pacella, Jennifer Angelopoulos, and Elizabeth Kennedy Hart for data collection; and Cecily Lewis for assistance in the preparation of the manuscript.
- Received September 20, 1999.
- Accepted December 23, 1999.
Reprint requests to (M.H.) Rainbow Babies and Children's Hospital, 11100 Euclid Ave, Cleveland, OH 44106. E-mail:
- SGA =
- small for gestational age •
- QuICCC =
- Questionnaire for Identifying Children With Chronic Conditions •
- IEP =
- Individualized Educational Plan
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- Copyright © 2000 American Academy of Pediatrics