Asthma symptoms ‘overestimated’ in obese children
medwireNews: Obese children with asthma may be overtreated, say US researchers who found that impaired mechanics of the chest, and not asthma itself, are responsible for some of the symptoms these patients experience.
Their study, published in TheJournal of Allergy and Clinical Immunology in Practice, shows that obese children did not have poorer asthma control than nonobese children or display a distinct TH1 or TH2 phenotype.
"Instead, children with obesity had a high frequency of comorbid conditions and nonspecific symptoms such as dyspnea and nocturnal awakenings that were not accompanied by greater airflow limitation or airway resistance," report authors Anne Fitzpatrick (Emory University, Atlanta, Georgia) and colleagues.
The study included 269 children with physician-confirmed asthma aged 6-17 years old, of whom 58 (21.6%) were classified as overweight (body mass index [BMI] 85-95th percentile for age and gender), and 67 (24.9%) were classified as obese (BMI >95th percentile).
Only 40 (15%) children met the criteria for "well-controlled" asthma but, after adjusting for age and gender, there was no association between asthma control and obesity. There was also no difference in airflow limitation, air trapping, airway resistance, or post-bronchodilator spirometry between the groups.
However, children with obesity had significantly lower functional residual capacity percentage predicted values compared with 144 children with a normal weight (BMI <85th percentile).
And, after adjusting for age, gender, and asthma control, children with obesity were 2.7-fold more likely to report dyspnea more than twice weekly, and 1.9-fold more likely to report nocturnal awakenings for asthma more than twice monthly.
Additionally, obese children had poorer asthma-related quality of life, had greater healthcare utilization, and were more likely to report that daily activities triggered their asthma symptoms than normal weight children.
The authors say their results suggest that poor asthma control may be overestimated in obese children. They note that obese children were more likely to receive systemic glucocorticoids but were not more likely to be hospitalized than normal weight children, which indicates that their symptoms are not intrinsically more severe.
"These results argue for careful evaluation of physiologic as well as symptom-based measures when initiating and evaluating asthma therapy in obese children," write Fitzpatrick and colleagues.
"Weight loss interventions may ultimately be necessary to improve asthma-related quality of life and associated symptoms in this population," they conclude.
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By Kirsty Oswald, medwireNews Reporter