In this epidemiological study we have studied during 1997 in Emilia-Romagna (population about four million) Italy, mortality from ischaemic heart disease, hypertension, cerebrovascular and respiratory disease in 50-89 year-olds. The data were collected from "Ufficio Risorse Informative" and "servizio Meteorologico" of the Emilia-Romagna region. The results show high indices of deaths in the elderly, the highest being those of the 80-89 year-olds, during the winter with a maximum in January. There were some differences between males and females with regard to cold-related mortality of the different diseases. Comparing mortality rates of persons living in the North (Piacenza) and in the South (Rimini) of Emilia-Romagna, a consistent lower mortality was found in the people of Rimini. These results confirm the close relationship between advanced age, cold and excess mortality in Emilia-Romagna. The results suggest that at least two factors may be involved in explaining excess winter mortality: the sympathetic system changes in the elderly and the effects of cold on some haemostatic factors.