The association between gender and pediatric respiratory morbidity.
OBJECTIVE
To evaluate the association between newborn gender and the risk for later pediatric respiratory morbidity.


STUDY DESIGN
A population based cohort analysis was performed by comparing the risk of long-term respiratory morbidity (until 18 years of age) according to gender. Respiratory morbidity included hospitalizations involving pneumonia, asthma, bronchitis, bronchiolitis, upper respiratory tract infection (URTI), influenza, and bronchiectasis. Deliveries occurred between the years 1991 and 2014 in a tertiary medical center. Kaplan-Meier survival curves were constructed to compare cumulative respiratory morbidity. A Cox proportional hazards model controlled for confounders.


RESULTS
During the study period 240 953 newborns met the inclusion criteria. Among them, 118 113 were females (49.0%) and 122 840 were males (51.0%). During the 18 years of follow-up, 13 719 (5.7%) different newborns were hospitalized with respiratory related morbidity. Males had significantly higher rates of respiratory morbidity as compared with females (6.4% vs 4.9% respectively, P < 0.001, OR 1.32, 95% CI 1.28-1.37). Specifically, pneumonia, bronchitis, asthma, bronchiolitis, and URTI were significantly more common in males. Males exhibited higher total cumulative respiratory morbidity (log rank P < 0.001), as well as higher cumulative morbidity in several sub-categories. These sub-categories included pneumonia, bronchitis, asthma, bronchiolitis, and URTI (P < 0.05 in all). The Cox regression model demonstrated male gender to be an independent risk factor for pediatric respiratory morbidity while adjusting for gestational age, birthweight, and other confounders (HR 1.29, 95% CI 1.25-1.34, P < 0.001).


CONCLUSIONS
Males are at an increased risk for pediatric respiratory morbidity, independent of obstetrical characteristics such as gestational age and birthweight.
['Ben-Shmuel|Atar|A|0000-0001-8200-1960', 'Sheiner|Eyal|E|', 'Wainstock|Tamar|T|', 'Landau|Daniella|D|', 'Vaknin|Flear|F|', 'Walfisch|Asnat|A|']
D000293:Adolescent D001249:Asthma D001724:Birth Weight D001988:Bronchiolitis D001991:Bronchitis D002648:Child D002675:Child, Preschool D015331:Cohort Studies D036861:Delivery, Obstetric D005260:Female D005865:Gestational Age D006760:Hospitalization D006801:Humans D007223:Infant D007231:Infant, Newborn D007251:Influenza, Human D007557:Israel D053208:Kaplan-Meier Estimate D008297:Male D009017:Morbidity D011014:Pneumonia D011247:Pregnancy D016016:Proportional Hazards Models D012141:Respiratory Tract Infections D012307:Risk Factors D012737:Sex Factors
gender respiratory morbidity epidemiology pulmonology