OBJECTIVE: To describe lung function findings in overweight children and adolescents without
respiratory disease. METHODS: This was a cross-sectional study involving male and female overweight children
and adolescents in the 8-18 year age bracket, without respiratory disease. All of
the participants underwent anthropometric assessment, chest X-ray, pulse oximetry,
spirometry, and lung volume measurements. Individuals with respiratory disease
were excluded, as were those who were smokers, those with abnormal chest X-rays,
and those with an SpO2 = 92%. Waist circumference was measured in
centimeters. The body mass index-for-age Z score for boys and girls was used in
order to classify the individuals as overweight, obese, or severely obese. Lung
function variables were expressed in percentage of the predicted value and were
correlated with the anthropometric indices.RESULTS: We included 59 individuals (30 males and 29 females). The mean age was 11.7 ± 2.7
years. Lung function was normal in 21 individuals (35.6%). Of the 38 remaining
individuals, 19 (32.2%), 15 (25.4%), and 4 (6.7%) presented with obstructive,
restrictive, and mixed ventilatory disorder, respectively. The bronchodilator
response was positive in 15 individuals (25.4%), and TLC measurements revealed
that all of the individuals with reduced VC had restrictive ventilatory disorder.
There were significant negative correlations between the anthropometric indices
and the Tiffeneau index in the individuals with mixed ventilatory disorder. CONCLUSIONS:Lung function was abnormal in approximately 65% of the individuals evaluated here,
all of whom were overweight. Obstructive ventilatory disorder and positive
bronchodilator response predominated.