Can seasonal di̇fferences affecti̇ve on frequency and mortali̇ty of pulmonary emboli̇sm?

Introduction: The influence of meteorological conditions oncardiovascular morbidity and mortality has been known for a long time. However, few reports have been published on the influence of seasonal differences on the pulmonary embolism (PE) which is the most serious clinical presentation occurrence of venous thromboembolism (VTE). There were periodic differences in the incidence of PE cases diagnosed in our clinic;so the aim of our study was to assess seasonal variation in the incidence of PE and to determine whether any differences in mortality. Materialand Method:Medical documantation of 402 patients diagnosed as acute PE by the Department of Chest Diseases in Afyon Health Sciences University Medical School Hospital in the five-year period between 01.01.2014 and 01.01.2019 were retrospectively analyzed. The study included patients aged 18 years and older who had a diagnosis of PE confirmed by spiral thorax CT.Age and gender of the patients, months of admission, radiological massive or nonmasif of PE, risk factors in PE development, main laboratory parameters (wbc, neutrophil, lymphocyte, hemoglobin, platelet, D-dimer, CRP), pulmonary artery pressurevalues, Wells scores, probability of PE development according to Wells scores, sPESI scores, treatments and prognosis were recorded. Results:The highest numbers of case were seen in spring (n=115,28,6%), followed by autumn (n=99,25%). The minimum number of patients was equal in winter and summer (n = 94, 23.4%). In terms of months, the greatest number of cases occurred in November (n=48,11,9%) and April (n=47,11,7%). Case distribution according to seasons and months were statistically significant (p<0,001). No seasonal differences in mortality rates were observed (p=0,663). No significant difference was found mortality rates by months (p = 0.582). Only the distribution of wbc level by the seasons was statistically significant among the recorded numerical data (p=0,045). The differences in mortality rates by numerical data (age, wbc, neutrophil, lymphocyte, plt, D-dimer, CRP, PAB values, aPESI and Wells scores) were statistically significant. Conclusion: Our observation that seasonal differences affective on frequency of PE has been confirmed. The highest numbers of case were seen in spring, however no seasonal differences in mortality rates were observed. There is now a need for further wide-ranging prospective studies including various hematological parameters and air pressure to explain the relationship between PE development and seasonal changes. Keywords: Pulmonary embolism, seasons, mortality