Upper respiratory infections as triggers of cardiovascular events

This research has been undertaken to study dynamics of mortality due to coronary heart disease (CHD) during 8-years period and its connection with morbidity of adults in St. Petersburg with influenza and acute respiratory diseases. The research was made on 34848 fatal cases of CHD from 1993 to 2000. Main statistical documents for choosing the reason of the death were the protocols of autopsy investigation and unified statistic chart of the sectioning that served together as a database. The mortality due to CHD was represented as a continuous time interval of 416 weeks corresponding to 8-years period. It has been revealed that CHD mortality increases in epidemic periods from November to April (6,8% of total mortality) and decreases in intervals May-October (2,1%). Relative medium risk of fatal outcome of CHD was increased 3,5-fold during epidemics of influenza and two-fold during period of increasing of morbidity due to respiratory diseases of unknown etiology. Weekly dynamics of fatal outcomes had no connection with main seasonal factors (temperature, atmosphere pressure, etc.).

CHD-based mortality increases during officially recognized influenza epidemics. Reliable connection with influenza epidemics is typical for aged people of both genders. Effect of infection on the mortality due to CHD may be notable during the period up to two weeks before fatal outcome, the period covering the active invasion of pathogen, receptor binding, colonization, action of exo- and endotoxins.