Adult Health Study (AHS)

The Adult Health Study (AHS) is a clinical research program based on biennial health examinations. Its major objective is to investigate the long-term effects of A-bomb radiation on health. About 20,000 subjects selected from the Life Span Study (LSS) cohort have been followed since 1958. Moreover, about 2,400 LSS participants and 1,000 in utero-exposed persons were added to the study in 1977. Then, about 2,000 LSS participants who were exposed when they were less than 10 years old were added in 2008. These additions brought the total number of LSS participants to approximately 25,400 persons. Of these individuals, health examinations for 5,000 persons who were not in the cities at the time of the bombings ended in 1977. Moreover, long-term observations of blood pressure readings, height and weight (BMI), and the like have been helpful for the study participants’ health management.

The major research elements of the AHS may be characterized as follows:

    1. 1.Relationship of radiation to non-cancer diseases (benign tumors, cardiovascular disease, and other chronic diseases)
    1. 2.Study of cancer mechanisms in relation to radiation and other risk factors
    1. 3.Aging and psychosocial changes associated with A-bomb radiation exposure
    1. 4.Radiation-related changes in physiological measurements
    1. 5.Medical dosimetry


In the AHS, the medical history of each individual (morbidity, treatment, examination, etc.) and information on lifestyle (exercise, nutrition, smoking, etc.) are collected. Therefore, an evaluation of radiation effects can take these factors into consideration. In addition to the general examination, special tests, such as measurement of bone mineral content and gynecological examinations, can also be conducted if warranted. Special emphasis is also placed on screening for skin, breast, and thyroid cancers, cataracts, and liver diseases. The results of each examination are reported to the individual.


The findings from this program are useful in other epidemiological studies as well. One is the Ni-Hon-San (Nippon [Japan], Honolulu, and San Francisco) cardiovascular disease study, in which the Adult Health Study participants are compared with persons of Japanese origin living in Honolulu and San Francisco to see how the differences in environment, diet, and lifestyle influence the incidence of cardiovascular diseases and mortality.