Además del artículo aparecido en el "British Medical Journal", que atribuye el aumento de muertes en invierno al frío y no a la gripe, otro estudio publicado en el "American Journal of Epidemiology", firmado por investigadores de la Universidad Johns Hopkins, indica que la población del sur de Estados Unidos es más vulnerable a los efectos del frío, que provoca un incremento de la mortalidad, mientras que la del norte sufre más los efectos del calor.
Analizaron la relación entre la latitud y la temperatura sobre la mortalidad en 11 grandes ciudades entre 1973 y 1994 para comprobar que las temperaturas extremas, tanto por calor como por frío, elevan los índices de mortalidad, especialmente en ancianos, indigentes y afectados por enfermedad respiratoria.
Webs Relacionadas
The Johns Hopkins University
http://www.jhu.edu/
American Journal of Epidemiology
http://aje.oupjournals.org/
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