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Etiology of Blood Dyscrasias: Analysis of the International Agranulocytosis and Aplastic Anemia Study Data

This study has been completed.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI) Identifier:
First received: May 25, 2000
Last updated: May 12, 2016
Last verified: May 2000
To quantify the role of drugs and other factors in the etiology of agranulocytosis and aplastic anemia.

Anemia, Aplastic Blood Disease Agranulocytosis

Study Type: Observational

Resource links provided by NLM:

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

Study Start Date: April 1989
Study Completion Date: March 1991
Detailed Description:


Agranulocytosis and aplastic anemia are rare but serious blood diseases that can be caused by drugs and other environmental factors. In 1980, there were only limited quantitative estimates of the risk between various exposures, particularly drugs, and the two dyscrasias. The data were collected in the IAAAS, a multicenter population-based case-control study conducted from 1980 to 1986 in eight regions. The study was funded by a pharmaceutical company to investigate a single hypothesis, but information was obtained on all drugs and on other factors, enabling a general investigation of the dyscrasias.


The study was for retrospective data analysis only. Standard case-control methods were used. In most instances, multivariate analysis was used to control confounding, especially by simultaneous use of other causal drugs. Adverse effects and the relative safety of drugs in relation to the two dyscrasias were documented. Because the IAAAS was population-based, incidence rates were provided directly, and excess risks were estimated for associated drugs. Such quantitative measures of association were generally unavailable. Among the drugs that were analyzed were various categories such as psychotropics, antihistamines, and cardiovascular drugs, and individual drugs such as allopurinol. Factors other than drugs were also evaluated, including exposure to radiation and chemicals such as benzene and insecticides, history of viral infection, and history of allergy and other conditions.

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


Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria
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  More Information

Publications: Identifier: NCT00005307     History of Changes
Other Study ID Numbers: 3009
R01HL042524 ( U.S. NIH Grant/Contract )
Study First Received: May 25, 2000
Last Updated: May 12, 2016

Additional relevant MeSH terms:
Hematologic Diseases
Anemia, Aplastic
Bone Marrow Diseases
Leukocyte Disorders processed this record on September 21, 2017