Meteorological parameters and severity of acute pulmonary embolism episodes

Frequency of acute pulmonary embolism episodes has been previously shown to correlate significantly with meteorological factors in the period preceding their occurrence. The purpose of the study was to analyze the relation of meteorological factors and the severity of acute pulmonary embolism, expressed by the CT-based pulmonary obstruction score. A retrospective analysis of medical data of 182 consecutive patients with acute pulmonary embolism diagnosed with CT pulmonary angiography was performed. Severity of pulmonary obstruction was assessed by analysis of CT pulmonary angiography examinations, and defined with pulmonary obstruction score by Qanadli et al. The study group was divided into low (L group, 95 patients) and high PE severity (H group, 87 patients), with a cutoff value of 50% of maximum pulmonary obstruction score. Meteorological data collected for the relevant time period were: air temperature, humidity, atmospheric pressure, visibility, wind speed and precipitation. No significant differences in seasonal distribution of pulmonary embolism episodes were observed. Episodes of more severe pulmonary embolism were preceded by periods of lower atmospheric pressure (1,016.35 hPA for group H, vs. 1,016.35 hPa for group L, p = 0.022). No significant relations between other meteorological factors and severity of PE were observed. The reported finding shows the need of further research on the nature of meteorological factors influence on the course of pulmonary embolism, which should be analyzed not ony regarding the frequency, but also severity of PE episodes.