[Seasonal variations and trends in cardiovascular disease mortality in Naples, 1974-1978].

Death certificates of people who died from cardiovascular diseases in the City of Naples from 1974 through 1978 were reviewed. Data were classified according to three different groups of causes of death: 1. from all cardiovascular diseases (codes of the International Classification of Diseases-ICD-, VIII Revision from 393.0 through 458.9), 2. from ischaemic heart diseases (ICD from 410.0 through 411.9) and 3. from acute ischaemic heart diseases (ICD from 410.0 through 411.9). The monthly number of deaths in each group was analyzed using time series techniques to assess the seasonal pattern and the secular trend. A clear seasonal pattern was found in all groups, though in group 3 it was less evident. The maximum number of deaths per month was found to occur during the cold season and the minimum during the summer. The secular trend was found to be stable for groups 1 and 2. Group 3 showed an evident increase over the five years under study.