Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00005438 |
| Other study ID # |
4366 |
| Secondary ID |
R29HL047872 |
| Status |
Completed |
| Phase |
N/A
|
| First received |
May 25, 2000 |
| Last updated |
May 12, 2016 |
| Start date |
February 1993 |
| Est. completion date |
January 1998 |
Study information
| Verified date |
November 2001 |
| Source |
National Heart, Lung, and Blood Institute (NHLBI) |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
United States: Federal Government |
| Study type |
Observational
|
Clinical Trial Summary
To identify those factors that contributed to cognitive deficiencies in children with sickle
cell disease (SCD) who had not demonstrated any overt or clinically apparent neurological
abnormalities.
Description:
BACKGROUND:
Although there has been evidence for a relationship between sickle cell disease and
pathology of the central nervous system since 1923, there has been a tendency in the
psychosocial literature to attribute any decreased cognitive performance in children with
sickle cell disease to illness-related or demographic factors (e.g., school absenteeism,
socioeconomic status) rather than to the disease process of SCD (e.g., chronic microvascular
insults to the central nervous system). Cerebral infarction is the most common neurological
complication that occurs in children with SCD, but clinically it presents itself in only
five to ten percent of children with this chronic illness. The majority of children with SCD
are also at high risk of demonstrating learning deficits and poor school performance.
Studies suggest that a significant number of children with SCD who do not display any overt
symptomatology of neurologic disease often exhibit decreased academic performance in
comparison to healthy matched peers. Given the pathophysiology of SCD, it is reasonable to
hypothesize that the insidious onset of impaired cognitive functioning is the result of
multiple microinfarcts, small hemorrhages, and progressive vascular disease. Therefore, the
disease process of SCD could be a primary contributing factor to long-term decreased
cognitive performance often demonstrated by the adult SCD population. It is thus critical to
examine young children with SCD who do not exhibit gross manifestations of neurological
insult in order to determine the cause of these cognitive deficits.
DESIGN NARRATIVE:
A total of 60 infants and toddlers with SCD and 60 matched normally-developing peers between
the ages of birth and three years served as subjects in a five-year longitudinal design in
order to permit between-group comparisons. Subjects were assessed at regularly scheduled
intervals with a variety of developmental (e.g., Bayley), cognitive (e.g., Stanford-Binet),
neuropsychological (e.g., Purdue Pegboard), family functioning, and physiological indices in
order to delineate those factors in the SCD group that were associated with decreased
cognitive and academic performance. A unique and important feature of this research was the
inclusion of magnetic resonance imaging technology. These techniques made it possible to
study in a comprehensive and componential manner the neuroanatomical effects of SCD instead
of relying on any single instrument or assessment to document this phenomenon. Goals of this
study included the identification of: (a) specific areas of learning deficiencies in
children with SCD; (b) the period in which these deficiencies began to occur; and (c) the
relationship between types of learning deficits and various outcome measures. In sum, this
study helped to determine how these factors interacted and changed over time as the child
with SCD matured, the disease fluctuated, and the family and/or the environmental context
changed in relation to cognitive development.
The study completion date listed in this record was obtained from the "End Date" entered in
the Protocol Registration and Results System (PRS) record.
