Spirometric reference standards for preschool children in Hong Kong

Area of Science:

• Pediatric Pulmonology
• Environmental Health
• Biostatistics

Background:

• Establishing normative data for lung function in children is crucial for diagnosing respiratory conditions.
• Incentive spirometry provides a method for assessing pulmonary function in young populations.
• Environmental tobacco smoke (ETS) is a known respiratory irritant in children.

Purpose of the Study:

• To develop prediction equations and normograms for spirometric parameters in Hong Kong Chinese children aged 2-6 years.
• To investigate the influence of various factors, including ETS exposure, on lung function in this cohort.
• To assess the relationship between urinary cotinine levels and spirometric measures.

Main Methods:

• Community-based cohort study involving 770 Hong Kong Chinese children aged 2-6 years.
• Incentive spirometry was used to measure spirometric parameters.
• Urinary cotinine levels were measured as a biomarker for ETS exposure.

Main Results:

• Standing height was the primary determinant of all spirometric parameters, with boys exhibiting higher values than girls.
• Forced expiratory volumes were influenced by birth weight, place of birth, wheezing history, and ETS exposure.
• Approximately 10% of children had high urinary cotinine levels, which were inversely associated with all spirometric parameters.

Conclusions:

• Prediction equations and normograms for spirometry in young children were established.
• ETS exposure, indicated by urinary cotinine, significantly impairs lung function in children.
• Findings support the implementation of smoking cessation programs to mitigate adverse respiratory effects.