29
(adult) statures and weights, measured at age 21
or older, of subjects exposed to radiation at age
< 17 indicated that those exposed in Hiroshima
attained a mean height markedly lower than normal and that the degree of retardation diminished
with increasing age at exposure, being greatest in
those exposed at age <5. The effect was more
prominentin boys. The preliminary tabulations
of growth data in the Marshallese children16-45
showedsimilar trends. Subsequently, the extent of
the thyroid injury documented in the Marshailese
children providedthe basis for the present assumption that growth retardation reflected primarily
the results of impaired thyroid function.It is anticipated that when adult(final) anthropometric
measurements become available, further evaluation of the growth pattern of the Marshallese children (including further assessmentof the effect of
thyroid hormone administration) will be possible.
G. DEGENERATIVE DISEASES
The aging process is accompanied by an increased incidence of degenerative diseases, and irradiated animals have shown increases both in
general aging phenomenaand in such diseases;
therefore, in these studies careful consideration has
been givento signs of aging andto the incidence
of cardiovascular diseases, arthritis, and other de-
generative diseases.
1. Cardiovascular Diseases
dividuals >40 years old have revealed the cardiac
changes ex
ith aging: arteriosclerosisheart
disease withootasionaltatdiac de
Auricutaryg
ation.
lay has -beerSoeditbe
people; rheumatic“heart ditease j Eneiro.
Peripheral vasctlar diseases (thrdmBophtEBitis,
peripheral venous disease, hemorrhoids) appear te
be less commonthan in Americans. Oscillonmetaft
studies showed peripheral: pulses to be éxieptionally good, even in older people andin diabetics
(see below). No luetic, metabolic, or nutritional
~
form of heart disease has beenen
seen.
co,
i$.
2. Arthritis
Med war
=
Many Marfhaliése,>40 yeats of age-complain
ofjoint symptoms in the arms and legs and toa
lesser extent in the lower back=Many,particularly
the older anes, Have compl@ined also of vague
muscige-]pains in the arms and legs.*Someolder
women develop marked. kyphosis in*ghe tower
thoracic-lumb
cegign—vchich maybaggelated
partly to the bagegiee
dFffooping position necessary for cooking over openfires. X rays show many
of the above complaints to be associated with
osteoarthritic changes; but many people with complaints do not have definite bone changes. Arthritis
seems no more commonin the exposed than tn the
unexposed population, and its general incidence
does not differ greatly from that among Americans. Rheumatoid arthritis has rarely been seen.
tefacter”
Examination of sheserttiog,
gave positive results in only a
cages{3 of 184
Cardiovascular diseases appear to be no more
prevalent among the Marshallese than in Americans or other populations, and no difference was
found between their incidences in the exposed and
unexposed groups. Hypertension appears to be
somewhatless prevalent among the Marshallese
than among Americans. Blood pressures > 140/90
tested in 1959).8
and the increasing percentage of older people in
Radiation in sublethal doses may reduce longe¥
ity in animals and man. Induction of malignant
transformationis well documented and accounts
for most of the early deaths. However, déevelopment of premature senescence with associated degenerative diseases and immunodeficiency, as a
late effect of exposure,is also believed to accountfor
some degree oflife shortening in animals.*7-49 For
humans, definite proof of such effects is lacking,
the only documentedlife-shortening effect being
related to malignancies.5°-5! In the Japanese bomb
survivors, the correlation oflife-shortening with
have been recordedin only about 9% of the people,
the study groups does not seem to have raised the
incidence of hypertension. Manyof the younger
people, particularly females, have notably lower
blood pressures (90-100/55-65). The generally
lower blood pressures in the Marshallese have been
thought to be related to lower dietary salt intake,7:46 but the gradually increasing use of imported foods of greater salt content has caused no
apparentincrease in hypertension. Serum sodium
and potassium levels have usually been in the normal range. Routine chest x rays and ECG’s on in-
Be Ae.
~ 1 rugs
3. Nephrosclerosis
0 Sees
Primary kidney disease has noibeen noted fré:
quently, but nephrosclerosis has occasionally|been
seen complicating cardiovascular disease.
4. Aging
=
3