Aim The association of outdoor air pollution and meteorological elements with primary care visits at night due to asthma attack was studied. Methods A case-crossover study was conducted in a primary care clinic in Himeji City, Japan. The subjects were 956 children aged 0-14 years who visited the clinic with an asthma attack between the hours of 9 p.m. and 6 a.m. Daily concentrations of particulate matter, ozone, nitrogen dioxide, and a number of meteorological elements were measured, and a conditional logistic regression model was used to estimate odds ratios (ORs) of primary care visits per unit increment of air pollutants or meteorological elements. The analyses took into consideration the effects of seasonality. Results Of the 956 children, 73 (7.6 %) were aged \2 years and 417 (43.6 %) were aged 2-5 years. No association between daily ozone levels and primary care visits due to asthma attack at night in the spring or summer was found. An inverse relation between suspended particulate matter and primary care visits due to asthma attack was detected in the winter. ORs in the summer per degree increment in daily mean temperature was 1.31 [95 % confidential interval (CI) 1.09-1.56], and ORs in the autumn per hourly increment in daily hours of sunshine was 0.94 (95 % CI 0.90-0.99). Conclusion The findings of our study fail to support any association between daily mean concentration of air pollutant and primary care visits at night. However, we did find evidence indicating that certain meteorological elements may be associated with primary care visits

ObjectiveWe examined the association of outdoor air pollution and meteorological parameters with primary care visits (PCVs) at night due to asthma attack.SettingA case-crossover study was conducted in a primary care clinic in Himeji City, Japan.ParticipantsParticipants were 1447 children aged 0–14 years who visited the clinic with an asthma attack from April 2010 until March 2013.ExposureDaily concentrations of air pollutants and meteorological parameters were measured.Primary outcomePCVs at night due to asthma attack. A conditional logistic regression model was used to estimate ORs of PCVs per unit increment of air pollutants or meteorological parameters (the per-unit increments of particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5) and ozone were 10 μg/m3 and 10 ppb, respectively). Analyses took into consideration the effects of seasonality.ResultsWe noted an association between PCVs and daily ozone levels on the day before a PCV (OR=1.17; 95% CI 1.01 to 1.35; p=0.04), as well as between PCVs and 3-day mean ozone levels before a PCV (OR=1.29; 95% CI 1.00 to 1.46; p=0.04), from April until June. We also observed an association between PCVs and daily PM2.5 levels on the day before a PCV from December until March (OR=1.16; 95% CI 1.01 to 1.33; p=0.05). Meteorological parameters, such as hours of sunshine from September until November, atmospheric pressure from April until June, and temperature from April until August, were also found to be associated with PCVs.ConclusionsThe findings in the present study supported an association between ozone and PCVs and suggest that certain meteorological items may be associated with PCVs.

IntroductionGuide sheaths (GSs) have been widely used during radial probe endobronchial ultrasound-guided transbronchial biopsy (rEBUS-TBB) of peripheral pulmonary lesions. However, it remains unknown whether a GS enhances the diagnostic yield. We compared the diagnostic yields of small peripheral pulmonary lesions between rEBUS-TBB with and without a GS.MethodsIn eight institutions, patients with peripheral pulmonary lesions≤30 mm in diameter were enrolled and randomized to undergo rEBUS-TBB with a GS (GS group) or without a GS (non-GS group) using a 4.0-mm thin bronchoscope, virtual bronchoscopic navigation, and fluoroscopy. The primary endpoint was the diagnostic yield of the histology specimens.ResultsA total of 605 patients were enrolled; ultimately, data on 596 (300 in the GS group and 296 in the non-GS group) with peripheral pulmonary lesions having a longest median diameter of 19.6 mm were analyzed. The diagnostic yield of histological specimens from the GS group was significantly higher than that from the non-GS group (55.3% versus 46.6%, respectively; p=0.033). Interactions were evident between the diagnostic yields, procedures, lobar locations (upper lobe versus other regions, p=0.003), and lesion texture (solid versus part-solid nodules, p=0.072).ConclusionsThe diagnostic yield for small peripheral pulmonary lesions afforded by rEBUS-TBB using a GS was higher than that without a GS.

Aim In January 2013, extremely high concentrations of fine particles (PM 2.5 ) were observed around Beijing, China. In Japan, the health effects of transboundary air pollution have been a matter of concern. We examined the association between the levels of outdoor PM 2.5 and other air pollutants with primary care visits (PCVs) at night due to asthma attack in Himeji City, western Japan. Methods A case-crossover study was conducted in a primary care clinic in Himeji City, Japan, involving 112 subjects aged 0-80 years who visited the clinic due to an asthma attack between 9 p.m. and 6 a.m. during the period January-March, 2013. Daily concentrations of particulate matter, ozone, nitrogen dioxide, and some meteorological elements were measured, and a conditional logistic regression model was used to estimate the odds ratios (OR) of PCVs per unit increment in air pollutants or meteorological elements. Results Of the 112 subjects, 76 (68 %) were aged \15 years. We did not note any association between daily PM 2.5 levels and PCVs due to asthma attack at night. A positive relation between ozone and PCVs due to asthma attack was detected. The OR per 10 ppb increment in daily mean ozone the day before the visit was 2.31 (95 % confidence interval 1.16-4.61). Conclusion These findings do not support an association between daily mean concentration of PM 2.5 and PCVs at night. However, we did find evidence suggesting that ozone is associated with PCVs.