Gender differences in hospitalization rates for respiratory tract infections in Danish youth

Abstract

Overall morbidity and mortality rates in childhood are reported to be higher in males than females. As respiratory tract infections constitute the leading cause of childhood hospitalization, we examined the gender difference in rates of hospitalization due to respiratory tract infections in Danish youth (under age 25). We studied a total of 64,049 hospitalizations for otitis media, pneumonia, influenza, and other acute respiratory tract infections from 1995 to 1999, with calculation of hospitalization rates by age and gender. The male-female hospitalization rate ratio (HRR) for admission due to a respiratory tract infection decreased from 1.45 (95% confidence interval (CI) 1.42-1.48) in the age group 0 - < 5 y, to 1.62 (95% CI 1.55-1.70) in the age group 5 - < 10 y, 1.13 (95% CI 1.04-1.22) in the age group 10 - < 15 y, 0.83 (95% CI 0.76-0.90) in the age group 15 - < 20 y, and 0.87 (95% CI 0.80-0.95) in the age group 20 - < 25 y. In young children, boys were hospitalized more often than girls, but the reverse applied in children and adolescents 15-25 y of age. The study generates the hypothesis that gender plays a role in the susceptibility for respiratory infections in early childhood.

Coarse Particulate Matter and Hospitalization for Respiratory Infections in Children Younger Than 15 Years in Toronto: A Case-Crossover Analysis

“…There is a reasonably good correlation between PM 10 -2.5 from dichotomous monitor and TEOM coarse fraction. The correlation was 0.85 between dichotomous PM 10 -2.5 and the difference between TEOM PM 10 and TEOM PM 2.5 at 1 site that had all 3 measures. The correlation was 0.74 when the values were averaged over all sites.…”

“…The adjusted OR for a 6-day average exposure to PM 10 -2.5 with an increment of 6.5 g/m 3 was 1.15 (95% CI: 1.02-1.30) for boys and 1.18 (95% CI: 1.01-1.36) for girls. The corresponding OR for PM 10 with an increment of 12.5 g/m 3 was 1.25 (95% CI: 1.01-1.54) in boys. There was no significant association between fine particulate matter (PM 2.5 ) and hospitalization for respiratory infections in boys, girls, or children as a whole when gaseous pollutants were taken into account.…”

“…Particulate matter was also taken into account when the relationships between gaseous pollution and hospitalization for respiratory infections were examined. Because thoracic particulate matter (PM 10 ) is a function of fine (PM 2.5 ) and coarse (PM 10 -2.5 ) particulate matter, only fine and coarse particulate matter were considered in the analyses of gaseous pollutants in relation to hospitalization for respiratory infections.…”

“…CO was measured using nondispersive infrared spectrometry, NO 2 was measured using chemiluminescence, O 3 was measured using chemiluminescence/ultraviolet photometry, and SO 2 was measured using coulometry/ultraviolet fluorescence. PM 2.5 and PM 10 were measured using tapered element oscillating microbalance (TEOM) instruments. Although PM 10 and PM 2.5 TEOM samplers were not necessarily co-located, we computed the average coarse fraction (PM 10 -2.5 ) as average PM 10 minus average PM 2.5 among sites in Toronto.…”

“…9 Children generally breathe more rapidly than adults, they may have more exposure to air pollutants per kilogram of body weight, and respiratory infections are generally more common in boys than in girls. 10 So far it has not been clear whether there are gender differences in effects of ambient air pollutants on respiratory infections in children. 11,12 This study used a case-crossover design to examine the association between ambient air pollution and respiratory infections in boys, girls, and children as a whole who were younger than 15 years in Toronto, Ontario, Canada.…”