A Medico-Climatological Study in the Seasonal Variation of Mortality in the United States of America (I)

Features of Seasonal Variation of Mortality

Abstract

In the United States of America, the seasonal fluctuation of the death index by age is found to be rather moderate for all the age groups, and little variation is seen particularly for infants. On the other hand, the death index curve rises for old age groups, though much less sharp than in the United Kingdom and Japan, in the cold season. Generally speaking, the moderate curve of the death index is ascribed to the wider use of the effective room heating system: that is, protected by the artificial weather thus brought about, the American people do not appear to be affected by the seasonal change so markedly as other nations.
It is worth mentioning however, that the death index curve behaves differently for the Whites and Nonwhites. Two peaks appear for the latter, one in summer and the other in winter, whereas only one summit appears in winter for the former. Based upon the extensive study of mortality statistics in Japan and other countries, this can be said to have resulted from the lower standard of living granted to the Nonwhites in the United States.
As the r e sult of our study in the seasonal variation of mortality, particularly that by age group, in the United States, it has become clear that the death index curve in that country widely differs from that in England (including Wales) and Japan. This is a preliminary report, which will be followed by additional analyses.