Airborne water droplets in mist or fog may affect nocturnal attacks in asthmatic children.

Our study objectives were to evaluate whether or not airborne water droplets in mist or fog affect the occurrence of nocturnal attacks of asthmatic children using a retrospective study. This study included 971 visits by children with bronchial asthma to the emergency department at nighttime (from 18:00 to 09:00) during a 3-year period (April 1, 1998-March 31, 2001). Meteorological data were checked at a local fire station and regional meteorological observatory. We divided nighttime into five 3-hour periods to evaluate the relationship between chronological changes in the frequency of the emergency department visits of asthmatic children and of meteorological conditions. In four of five periods of nighttime, multivariate analysis showed that mist or fog, average atmospheric temperature, and barometric pressure were related to the number of emergency department visits (n=1096, r=0.165-0.263, p<0.0001). We divided the year into four seasons to eliminate differences between atmospheric temperature and barometric pressure on clear nights and on misty or foggy nights; we also found the mean number of emergency department visits was higher on misty or foggy nights than on clear nights in each seasonal period (p<0.01). In addition, average atmospheric temperature on misty or foggy nights with the emergency department visits was higher than that on misty or foggy nights without any visits (p<0.01). Asthmatic children frequently visited the emergency department on misty or foggy nights, especially during midnight to dawn periods with high atmospheric temperature. Because a higher atmospheric temperature on misty or foggy nights indicates a larger saturated amount of airborne water droplets, our results suggest that mist and fog, in particular a saturated amount of airborne water droplets, may be a stimulus for bronchoconstriction.

Outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor.

GOALS OF THE STUDY: To evaluate the outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor. PATIENTS AND METHODS: This study enrolled 198 asymptomatic patients with lung cancer found by lung cancer mass screening during the 9-year period. Five-year survival rates in patients who did not consult a doctor or who stopped consulting a doctor in spite of abnormal shadows detected on last mass screening chest roentgenograms (n=45, delayed consultation group) and in patients who subsequently consulted a doctor when abnormal shadows were detected (n=153, control group) were evaluated by the method of Kaplan and Meier and clinical variables were examined as possible predictors of survival time by the Cox proportional-hazards model. RESULTS: There was a significant difference between the 5-year survival rates in the delayed consultation group and in the control group (21 vs. 51%, log rank: P=0.0003, Wilcoxon: P=0.0009). The risk of death increased 115.0% for the 1-year delay in consultation (hazard ratio: 2.150, 95% CI: 1.203-3.842, P=0.0097). With regard to the reason why they did not consult a doctor, many of them answered that they did not have any respiratory symptoms. CONCLUSION: The 1-year delay in consultation had a great significance in that these patients did not receive any treatment for lung cancer for 1 year, and the 1-year delay in treatment itself affected the outcome.