Meteorological parameters and seasonal variations in pulmonary thromboembolism.
OBJECTIVE
In recent years, circannual variations in incidence and mortality for venous thromboembolic disease have been demonstrated, with a peak in winter. However, several investigators have observed no seasonal variation in these diseases. The aim of our study was to investigate whether a seasonal variation, in terms of atmospheric pressure, humidity, and temperature, exists for pulmonary thromboembolism.


METHODS
We retrospectively included 206 patients with a diagnosis of pulmonary embolism (PE) between 1 June 2001 and 31 May 2006.


RESULTS
The highest number of cases in the 5 years concerned occurred in May (29 cases). Although PE occurred most commonly in the spring (72 cases) and autumn (51 cases), the difference was statistically significant (P = .003). There were no case correlations with months and pressure, temperature, or humidity. However, there was a statistically significant positive correlation between case incidence and atmospheric pressure (r = 0.53, P < .0005) and humidity (r = 0.57, P < .0005). In terms of risk factors, seasonal distribution was not statistically significant as regards cases of embolism occurring for surgical or nonsurgical reasons (r = 0.588).


CONCLUSIONS
In terms of the relationship between seasons and embolism cases, despite the determination of an insignificant positive correlation, a statistically significant positive correlation was determined between air pressure and humidity and case incidence. There is now a need for further wide-ranging prospective studies including various hematological parameters to clarify the correlation between PE and air pressure.
Oztuna
Funda
F
Department of Chest, School of Medicine, Karadeniz Technical University, 61080 Trabzon, Turkey. foztuna@yahoo.com
Ozsu
Savaş
S
Topbaş
Murat
M
Bülbül
Yilmaz
Y
Koşucu
Polat
P
Ozlü
Tevfik
T
D000368:Aged; D000399:Air Pressure; D000792:Angiography; D002980:Climate; D005260:Female; D006801:Humans; D006813:Humidity / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D012189:Retrospective Studies; D012621:Seasons; D014421:Turkey