RP 2-99

Thyroid Diseases in Hiroshima and Nagasaki Atomic-Bomb Survivors


The effect of atomic-bomb radiation on thyroid diseases will be analyzed in 5,489 Adult Health Study (AHS) participants in Hiroshima and Nagasaki to elucidate thyroid disease incidence. All subjects will undergo thyroid gland palpation, function testing, autoantibodies testing, and ultrasound examination. The previous thyroid study conducted in Nagasaki from 1984 to 1987 demonstrated increased thyroid tumor prevalence and a radiation-dose-response relationship in autoimmune hypothyroidism among atomic-bomb survivors. This study will assess whether there is a closer relationship between these diseases and radiation dose after more than ten years. This is the first thyroid disease prevalence study of the Hiroshima AHS since1971. Previously detected solitary thyroid nodules will be investigated by precise ultrasound nodule-volume measurement.