Medical Student Research Fellowship for Summer 2009
Principal Investigator: Charles T. Quinn, MD
Phone: 214-648-3896
Location: F03.228
Email: Charles.Quinn@UTSouthwestern.edu
Title: Burden of Radiation Exposure in Children with Sickle Cell Disease
Sponsor/Funding Source: The University of Texas Southwestern Medical Center
at Dallas
Purpose:
The purpose of this study is to quantify the exposure to radiation from diagnostic
studies that children with sickle cell disease received during the course of
their standard clinical care. Medical records will be reviewed to determine
the type and number of each patient's radiographic studies from January 1, 1996
to the present (April 1, 2009)??? (the electronic medical record era). From
these data, we can calculate patients' cumulative radiation exposure. The additional
burden of radiation as compared to ……, or increase risk in latter
decades, will we potentially change how we do business? If the burden is huge?
Background:
Children with sickle cell disease may present to medical attention repeatedly
throughout childhood for complications of their disease. Chest radiographs are
obtained for fever and respiratory symptoms. Plain radiographs are often ordered
because of bone pain. Computed tomography and nuclear medicine studies may also
be obtained for other complications. Because children with sickle cell disease
have the potential to be exposed to so much radiation throughout their lifetime,
it is important to determine the risk of this exposure. [WHY??] We will quantify
for the first time this radiation exposure. Exposure to medical irradiation
may increase the risk of radiation-related morbidity. [1]
Concise Summary of Project:
This retrospective chart review will study members of the Dallas Newborn Cohort.[2]
Epidemiologic studies of this cohort are approved by The UT Southwestern IRB
(IRB #0302 173). The electronic sickle cell disease database will be queried
to identify subjects. The electronic medical record system of Children's Medical
Center Dallas will be reviewed for each patient to determine the number and
type of radiographic studies each patient received from January 1, 1996 to the
present. Paper-based and archived medical records will be reviewed if necessary
for confirmation of irregular data and to obtain any missing data. All data
is pre-existing in the subject's medical record and was collected for clinical
purposes at the time of the encounter. For each patient identified we will obtain
general demographic information to use during the data extraction only. Additional
data to be collected includes: date of radiation exposure, type, # of views,
# of locations, specific location, current treatments, reason for exposure,
expected information obtained. Specific information can be found on the attached
data collection sheets (see Appendix ##).
Study Procedures:
1. Review of medical records. There will be no direct contact with patients
or families and no treatment of any kind given as part of this study.
2. Statistical analysis of the data.
Inclusion Criteria:
1. Member of Dallas Newborn Cohort (IRB #0302 173)[2]
2. Diagnosis of sickle cell anemia (SS), sickle-hemoglobin C disease (SC), sickle-
+-thalassemia, or sickle- 0-thalassemia.
Exclusion Criteria: None
Sources of Research Material:
Medical records (electronic records at Children's, sickle cell database, sickle
cell clinic shadow charts, and paper copies of records and microfilm in selected
cases) will be used to identify the information which will be gathered on the
data collection sheets.
Recruitment:
There will be no direct patient contact as part of this study. The Sickle Cell
database will be queried for all patients meeting the criteria between January
1, 1996 and April 1, 2009. Obtaining informed consent is not practical because
this is a retrospective review.
Potential Risk:
There is a possible risk of the loss of confidentiality by inadvertent release
of protected health information. Patient information will be stored in a password
protected database. Only members of the research team will review charts and
have access to the database. Statisticians involved in the project will have
access to de-identified data for the purposes of analysis
Special Precautions:
Data will initially have identifiers including name and medical record number
for collection and organizational purposes only. For analysis, all names and
identifiable links will be removed. For publication and presentation, no identifiable
information of any kind, including name, date of birth, individual health care
history, or medical record number will be used.
Procedures to maintain confidentiality:
Any information that is obtained in connection with this research that can be
identified with a subject will remain confidential. Patient information will
also be stored in a local (Children's Medical Center Dallas) password-protected
database on a password-protected computer. Any paper records will be kept in
a locked, badge-accessed file room in the Center for Cancer and Blood Disorders
at Children's Medical Center Dallas. Access to local research files will be
limited to the immediate research team listed in the NR1 and the Institutional
Review Board at UT Southwestern. Confidentiality of all medical records will
be maintained by assignment of passwords and electronic badge access privileges.
The IRB may need to view data for quality assurance and data management purposes.
Confidentiality of all medical records will be maintained by correct identification
of the appropriate person before viewing the medical record and ascertaining
the reason for the viewing of the medical records. Statisticians who might assist
in analyzing data will only see the de-identified data. Specific information
will not be shared with individual patients, but the collective data set after
analysis may be of interest to all patients.
Potential Benefits:
This study will increase our knowledge of the magnitude of exposure to radiation
that children with sickle cell disease receive during routine clinical care.
If we find this exposure to be associated with increased risk of radiation-related
morbidity (extrapolated from prior research), then future clinical practices
might be changed to improve patient safety.
Statistics:
This is a descriptive study. Standard radiation doses (e.g., estimated organ
doses) will be assigned to each type of radiographic study. The total radiation
dose will be calculated for each patient for the entire length of follow-up
(1996-2009). Summary statistics will be calculated for the entire cohort. The
cumulative incidence of radiation exposure (yes/no) will be determined for the
cohort. We will also explore whether there are differences in radiation exposure
by age.
References:
1. Brenner DJ, Hall EJ. Computed tomography--an increasing source of radiation
exposure. N Engl J Med 2007:357(22):2277-2284.
2. Quinn CT, Rogers ZR, Buchanan GR. Survival of children with sickle cell disease.
Blood 2004:103(11):4023-4027.