Seasonal variations in respiratory system in healthy inhabitants of west Siberia.

Abstract

The aim of this work was to investigate seasonal variations in oxygen consumption, ventilation, lung volumes and their relationships in healthy adult inhabitants of West Siberia. The investigations were performed in Novosibirsk. Thirty healthy male adult volunteers were studied 4 times during a year: in summer (mean monthly temperature +20 degrees C), autumn (+2 degrees C), winter (-18 degrees C), and spring (degrees C) under the same conditions in a room at rest. Oxyspirography, pneumotachography and the helium dilution method were used. Oxygen consumption (VO2), breathing frequency, vital capacity (VC) and inspiratory capacity were adjusted to be the same during the year. Minute ventilation (Ve), VO2-Ve ratio, residual volume (RV) and expiratory reserve volume (ERV) to RV ratio had dynamics concurrent with seasonal temperature dynamics. Tidal volume, ERV, functional residual capacity, forced 1-s expired volume (FEV1) and FEV1/VC also changed, but their dynamics were different from the previous parameters. The minimum value of these parameters was found in the spring and the maximum--in the autumn, or summer and autumn. Correlations between respiratory parameters also changed during the year. We conclude that oxygen consumption is provided by reorganisation of pulmonary tissue in winter.