Association between quality of life, severity of asthma, sleep disorders and exercise capacity in children with asthma: a cross-sectional study.

OBJECTIVE

To assess the association between quality of life, asthma severity, sleep disorders and exercise capacity in children with asthma.

METHODS

We evaluated 45 children with asthma of both sexes aged between 7 and 12 years, diagnosed by a pediatrician/pulmonologist and classified according to the IV Brazilian Guidelines for Asthma Management: severity (intermittent/mild and moderate/severe) and control (controlled, partially controlled and uncontrolled). Quality of life (QoL), presence of sleep disorders and exercise capacity were respectively assessed using the following instruments: Pediatric Asthma Quality of Life Questionnaire (PAQLQ); Sleep Disturbance Scale for Children (SDSC); and six-minute step test (6MST).

RESULTS

Intermittent/mild and moderate/severe asthma were observed in 51.1% and 48.9% of the children evaluated, respectively. Only 8.89% of the sample had uncontrolled asthma. In the regression model, a better QoL was observed in children with lower asthma severity, lower SDSC total score and lower levels of dyspnea induced by the 6MST (β=-0.395, p=0.003; β=-0.338, p=0.011; β=-0.352, p=0.008; respectively). These factors explained 31% of the PAQLQ total score variation. Other variables (such as cardiorespiratory variables, spirometry, asthma control and number of steps in 6MST) did not predict quality of life.

CONCLUSIONS

Lower asthma severity (intermittent/mild), fewer symptoms of sleep disorder, and lower exercise-induced dyspnea predicts better quality of life in children with asthma.