TY - JOUR
T1 - The role of outdoor fungi on asthma hospital admissions in children and adolescents
T2 - A 5-year time stratified case-crossover analysis
AU - Tham, Rachel
AU - Katelaris, Constance H.
AU - Vicendese, Don
AU - Dharmage, Shyamali C.
AU - Lowe, Adrian J.
AU - Bowatte, Gayan
AU - Taylor, Philip
AU - Burton, Pamela
AU - Abramson, Michael J.
AU - Erbas, Bircan
PY - 2017/4/1
Y1 - 2017/4/1
N2 - Background Some fungal spores can trigger asthma exacerbation but knowledge of which outdoor fungal spores contribute to asthma hospitalisation is limited. Objectives To examine the role of outdoor fungal spores in child and adolescent asthma hospitalisations. Methods We conducted a bi-directional time-stratified case-crossover study of child and adolescent asthma hospitalisations over 5 years. Conditional logistic regression assessed the role of 20 fungi taxa (Same day [L0] and lagged [L1-3]) adjusted for maximum temperature, humidity and grass pollen. Strata specific effects were explored if there was evidence of effect modification by age, sex, air pollutants or grass pollen. Non-linear effects examined with Generalized Additive Models. Results Of 2098 children hospitalised for asthma, 60% were boys; mean age was 5.5±3.7 years. Fungal spore counts peaked during warm months. Regression models found weak associations with Coprinus [L0,L1: OR=1.03, 1.01–1.06], Periconia [L0: OR=1.03, 1.001–1.07] and Chaetomium [L2: OR=1.08, 1.0–1.2]. Sex appeared to act as an effect modifier with girls having stronger associations with Cladosporium, Coprinus and total fungi. Older adolescent (14–18 years) hospitalisation was significantly associated with Coprinus and Ustilago/smuts. Air pollutants and grass pollen did not appear to act as effect modifiers. Non-linearity was not detected. Conclusion There may be associations between some outdoor fungal spores and asthma hospitalisations. Further research needed to explore whether these findings can be replicated; and examine whether fungal sensitisation and/or human rhinovirus infections are associated with stronger effects. If findings are replicated, then the need to develop predictive models for fungal spore distribution and levels may become more important.
AB - Background Some fungal spores can trigger asthma exacerbation but knowledge of which outdoor fungal spores contribute to asthma hospitalisation is limited. Objectives To examine the role of outdoor fungal spores in child and adolescent asthma hospitalisations. Methods We conducted a bi-directional time-stratified case-crossover study of child and adolescent asthma hospitalisations over 5 years. Conditional logistic regression assessed the role of 20 fungi taxa (Same day [L0] and lagged [L1-3]) adjusted for maximum temperature, humidity and grass pollen. Strata specific effects were explored if there was evidence of effect modification by age, sex, air pollutants or grass pollen. Non-linear effects examined with Generalized Additive Models. Results Of 2098 children hospitalised for asthma, 60% were boys; mean age was 5.5±3.7 years. Fungal spore counts peaked during warm months. Regression models found weak associations with Coprinus [L0,L1: OR=1.03, 1.01–1.06], Periconia [L0: OR=1.03, 1.001–1.07] and Chaetomium [L2: OR=1.08, 1.0–1.2]. Sex appeared to act as an effect modifier with girls having stronger associations with Cladosporium, Coprinus and total fungi. Older adolescent (14–18 years) hospitalisation was significantly associated with Coprinus and Ustilago/smuts. Air pollutants and grass pollen did not appear to act as effect modifiers. Non-linearity was not detected. Conclusion There may be associations between some outdoor fungal spores and asthma hospitalisations. Further research needed to explore whether these findings can be replicated; and examine whether fungal sensitisation and/or human rhinovirus infections are associated with stronger effects. If findings are replicated, then the need to develop predictive models for fungal spore distribution and levels may become more important.
KW - Adolescent
KW - Asthma hospitalisations
KW - Case cross-over
KW - Child
KW - Outdoor fungi
UR - http://www.scopus.com/inward/record.url?scp=85007251520&partnerID=8YFLogxK
U2 - 10.1016/j.envres.2016.12.016
DO - 10.1016/j.envres.2016.12.016
M3 - Article
AN - SCOPUS:85007251520
SN - 0013-9351
VL - 154
SP - 42
EP - 49
JO - Environmental Research
JF - Environmental Research
ER -