nitrogen-dioxide and Croup

To assess the impact of short-term exposure to air pollution on respiratory illness in children we recruited pediatricians and hospitals in five German cities to report daily counts of children's visits for croup symptoms and obstructive bronchitis. Data were collected for at least 2 years in each location. These symptoms are predominantly found in very young children, with the croup reporting peaking at 2 years of age and obstructive bronchitis at 1 year. Attacks of croup and obstructive bronchitis were relatively rare events: the mean number of cases of croup per day in each city ranged from 0.5 to 3, and obstructive bronchitis was even less frequent. A total of 6330 cases of croup and 4755 cases of obstructive bronchitis were observed during the study. The distributions of these events were quite skewed and were modeled as a Poisson process. To focus the analysis on short-term correlations and avoid seasonal confounding, biannual, annual (seasonal), and six shorter term cycles were controlled for in the regression models. After controlling for short-term weather factors, total suspended particulate matter (TSP) and nitrogen dioxide (NO2) were associated with croup cases. An increase in TSP levels from 10 micrograms/m3 to 70 micrograms/m3 was associated with a 27% increase in cases of croup; the same increase in NO2 levels resulted in a 28% increase in cases. No pollutant was associated with daily cases of obstructive bronchitis.

Topics: Air Pollution; Bronchitis; Child, Preschool; Croup; Female; Germany; Humans; Infant; Longitudinal Studies; Male; Nitrogen Dioxide; Poisson Distribution; Regression Analysis; Seasons; Sex Factors; Sulfur Dioxide

Topics: Air Pollutants; Bronchitis; Child; Croup; Dust; Germany, West; Humans; Laryngitis; Longitudinal Studies; Maximum Allowable Concentration; Nitrogen Dioxide; Risk; Smog; Sulfur Dioxide; Temperature; Weather

Between 1971 and 1983 admissions with croup syndrome to two hospitals for children were recorded. During this time 1926 patients were hospitalized in Mannheim and 661 patients in Darmstadt. Air pollution by SO2, NO2, NO, CO, O3 and dust were measured. In Darmstadt no correlation was found between croup and air pollution, while in Mannheim, monthly averages of SO2, NO2, NO and CO showed linear correlations with monthly cases of croup.

Topics: Air Pollution; Carbon Monoxide; Child; Cross-Sectional Studies; Croup; Dust; Germany, West; Humans; Laryngitis; Nitrogen Dioxide; Nitrous Oxide; Ozone; Seasons; Sulfur; Sulfur Dioxide