Respiratory symptoms and fractional exhaled nitric oxide (FeNO) among students in Penang, Malaysia in relation to signs of dampness at school and fungal DNA in school dust

Abstract

• Elevated FeNO, a marker of lower airway inflammation, was found in many students.• Signs of dampness in the classroom were related to airway infections among students.• Students in classrooms with signs of dampness had 31% higher FeNO values.• Higher quantities of DNA from Aspergillus versicolor were related to higher FeNO.• DNA from Aspergillus versicolor were related to asthma and respiratory symptoms. Few health studies exist on dampness and mould in schools in the tropics. We studied associations between fraction of exhaled nitric oxide (FeNO), respiratory symptoms and airway infections among students and dampness and fungal DNA in schools in Malaysia. A total of 368 randomly selected students from 32 classrooms in 8 secondary schools in Penang, Malaysia, participated (58% participation rate). Information on current respiratory symptoms and the home environment was collected by a standardised questionnaire. FeNO was measured by NIOX MINO (50 ml/min). The classrooms were inspected and dust was collected by vacuuming on special filters and was analysed for five fungal DNA sequences by quantitative PCR. Linear mixed models and 3-level multiple logistic regression (school, classroom, student) were applied adjusting for demographic data and the home environment. Totally 10.3% reported doctor's diagnosed asthma, 15.1% current wheeze, 12.4% current asthma, 37.3% daytime breathlessness, 10.2% nocturnal breathlessness, 38.9% airway infections and 15.5% had pollen or furry G R A P H I C A L A B S T R A C T a b s t r a c t a r t i c l e i n f o Contents lists available at ScienceDirectScience of the Total Environment j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / s c i t o t e n v pet allergy. The geometric mean of FeNO was 19.9 ppb and 45% had elevated FeNO (N20 ppb). Boys had higher levels of FeNO. Chinese had less daytime breathlessness than Malay (OR = 0.30: p b 0.001). Indoor carbon dioxide levels were low (380-720 ppm). Dampness was observed in 18% of the classrooms and was associated with respiratory infections (OR = 3.70; 95% CI 1.14-12.1) and FeNO (p = 0.04). Aspergillus versicolor DNA was detected in 67% of the classrooms. Higher numbers of Aspergillus versicolor DNA in classroom dust were associated with wheeze (p = 0.006), current asthma (p = 0.002), respiratory infections (p = 0.005) and elevated FeNO levels (p = 0.02). In conclusion, respiratory symptoms were common among the students and the high FeNO levels indicate ongoing airway inflammation. Building dampness and the mould Aspergillus versicolor in schools in Malaysia can be risk factors for impaired respiratory health among the students.

Sick building syndrome: are we doing enough?

“…Building dampness is the presence of unwanted moisture in the building structure, which can be either the result of intrusion from outside or condensation within the structure. This phenomenon may stimulate the appearance of respiratory illness such as asthma in occupants (Choi, Schmidbauer, and Bornehag 2017;Norbäck et al 2017;Wang et al 2017). Takeda et al (2009) identified dampness as one of the critical factors associated with SBS symptoms in newly built dwellings.…”

Home dampness-related exposures increase the risk of common colds among preschool children in Shanghai, China: Modified by household ventilation

“…[16] performed the research on the association between home dampness and asthma related symptoms among pre-school children of Shanghai during 2011e2013. Norback D., et al [17] studied associations between fraction of exhaled nitric oxide (FeNO), respiratory symptoms and airway infections among students and dampness and fungal DNA in schools in Malaysia. They found that building dampness and the mound aspergillus versicolor in schools in Malaysia can be risk factors for impaired respiratory health among the students.…”

Onset and remission of rhinitis among students in relation to the home and school environment—A cohort study from Northern China

“…A further limitation is that data on the home environment and rhinitis were assessed by a questionnaire. However, the questions on the home environment have been used in previous studies . We did not ask about number of siblings in our study, as the one child policy was still valid when we did our study (2010‐2012).…”

“…The self‐administered questionnaire included questions on rhinitis and the home environment, using the same questionnaire in 2010 and 2012. The questionnaire has been used in our previous school studies in Asia . There were questions on gender, age, smoking habits, cat, dog, and pollen allergy and parental asthma or asthma.…”

“…The questionnaire has been used in our previous school studies in Asia. 17,[24][25][26] There were questions on gender, age, smoking habits, cat, dog, and pollen allergy and parental asthma or asthma.…”