NAS-NRC Twin Registry

BACKGROUND: The registry of World War II veteran twins came into existence in the late 1960's through a search and link effort of state vital statistics records and Veterans Administration files through the Medical Follow-up Agency of NAS-NRC. Since that time, the registry has served as a data resource for investigators in a variety of scientific fields who want to study genetic and environmental aspects of various human characteristics. Because of the size and geographic coverage throughout the United States, the registry offers a method of recruiting sizeable numbers of twins for study even under geographic restrictions. Of special value to medical researchers is the built-in medical follow-up for morbidity and mortality through Veterans Administration insurance and benefits records. This allows researchers to gather baseline data which may be related prospectively to morbidity and mortality events. The NHLBI has made extensive use of the World War II veteran twin registry beginning in 1969, when the NHLBI Twin Study was initiated. At that time, NHLBI used the World War II veteran twin registry to recruit a group of 514 pairs of twins in five geographic areas to participate in a study which included a battery of questionnaires and a physical examination. Since that time, a second examination and third examination of the cohort have been completed and the registry has been used to maintain contact with the twins and provide surveillance for morbidity and mortality events of the participants in the study. DESIGN NARRATIVE: Maintenance of the existing registry continued as addresses of all members were updated annually as well as morbidity and mortality data through surveillance of Veterans Administration insurance and death benefit records or through the National Death Index. All morbid events and deaths were coded by ICD codes. Support activities were provided for the NHLBI Twin Study including providing death certificates for events occurring among the 1,028 twins participating in the study and mailed questionnaire follow-up. Although contract support ended in September, 1988, analyses of the survey and mortality data are continuing.