Medical Student Research Fellowship for Summer 2009
Principal Investigator: Charles T. Quinn, MD
Title: Burden of Radiation Exposure in Children with Sickle Cell Disease
Sponsor/Funding Source: The University of Texas Southwestern Medical Center at Dallas
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?
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. 
Concise Summary of Project:
This retrospective chart review will study members of the Dallas Newborn Cohort. 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 ##).
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.
1. Member of Dallas Newborn Cohort (IRB #0302 173)
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.
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.
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
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.
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.
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.
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.