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Aplastic Anemia Epidemiology: Incidence and Case-control

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: May 26, 2000
Last Update Posted: February 18, 2016
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
To conduct incidence and case-control studies of aplastic anemia in metropolitan Bangkok, Thailand

Blood Disease Anemia, Aplastic

Study Type: Observational

Resource links provided by NLM:

Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: September 1988
Study Completion Date: August 1994
Detailed Description:


Aplastic anemia, a form of bone marrow failure, is a disease of largely unknown cause, except for the rare situations involving high doses of radiation. Many agents have been mentioned in case reports to be associated with the development of aplastic anemia and include drugs, chemicals, pesticides, radiation, and viral infection. Of these, chloramphenicol, phenylbutazone, and insecticides are most frequently reported. In the United States and other developed countries the disease prevalence is so low that too few cases occur to make an epidemiological study in a single city logistically feasible. The Bangkok hospitalization rate for aplastic anemia was sufficient to conduct a case-control study. Also, a study conducted in this locale provided information on drugs and chemicals not commonly used in developed countries.


All aplastic anemia cases in metropolitan Bangkok were located and verified in the forty hospitals that agreed to participate in the study. Incidence rates were calculated by age group and sex. In the case-control study, interviews were used to obtain comprehensive histories of drug, chemical, pesticide, radiation, viral infections, and other exposures, along with relevant demographic and medical history information in order to examine the association between and test hypotheses regarding suspected hazards and to estimate the risks of developing aplastic anemia. The basic epidemiologic features of aplastic anemia were described by characterizing these patients in terms of standard demographic variables, age, race, sex, and medical history. The degree of association between viral hepatitis and the development of aplastic anemia was estimated.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.


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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00005682

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: Paul Leaverton
OverallOfficial: Samuel Shapiro
  More Information


ClinicalTrials.gov Identifier: NCT00005682     History of Changes
Other Study ID Numbers: 3008
R01HL035068 ( U.S. NIH Grant/Contract )
First Submitted: May 25, 2000
First Posted: May 26, 2000
Last Update Posted: February 18, 2016
Last Verified: May 2000

Additional relevant MeSH terms:
Hematologic Diseases
Anemia, Aplastic
Bone Marrow Diseases