Seasonal and meteorological impacts on primary spontaneous pneumothorax

Background: Although several studies have suggested that primary spontaneous pneumothorax (PSP) might occur in clusters, only a few studies have found seasonal variations in PSP occurrence. Some meteorological parameters might be related to the occurrence of PSP occurrence, however, the effects of weather variations on the onset of PSP are still controversial. Methods: We examined seasonal differences in the occurrence of PSP and the meteorological risk factors for PSP. All PSP patients aged <40 years who were admitted to Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers from April 2007 through March 2013 were included in the study. Results: The incidence rates of PSP were 16.7 and 2.1 per 100,000 person-years in men and women, respectively. The frequency of PSP days among months and seasons was significantly different with a peak in September and autumn. Daily changes in maximum wind speed had positive associations with PSP days [crude OR =1.11 (95% CI: 1.02-1.21) per 1 m/s, P=0.02; multivariable-adjusted OR =1.11 (95% CI: 1.00-1.23) per 1 m/s, P=0.05]. Conclusions: PSP tends to cluster seasonally. Increased wind speed may play a role in the development of PSP.