Predictors of Asthma Control Differ From Predictors of Asthma Attacks in Children: The Swiss Pediatric Airway Cohort

To determine if the predictors of asthma attacks are the same as the predictors of asthma symptom control in children.This study includes patients from The Swiss Pediatric Airway Cohort, which is a multicenter prospective clinical cohort of children from 6 pediatric respiratory outpatient clinics across Switzerland. There were 516 patients (5–16 years old) who were diagnosed with asthma by a pediatric pulmonologist. Children with bronchopulmonary dysplasia were excluded.Baseline characteristics were collected at the beginning of the study, including sociodemographic information, symptoms, personal and family history, and environmental exposure from a baseline parent questionnaire. These were selected as potential predictors of poor asthma control and asthma attacks. Objective tests were also obtained, including forced expiratory volume for 1 second, forced vital capacity, forced expiratory flow 25 to 75, fractional exhaled nitric oxide, bronchodilator reversibility, and allergic sensitization to aeroallergens. Outcomes were assessed 1 year later through a questionnaire to parents. Suboptimal asthma control was defined following GINA guidelines, including answers on night wakening caused by wheeze, daytime wheezing, disturbance of daily activities, and the need for short-acting beta-agonists over a preceding 4-week period. Asthma attacks were defined as a worsening of asthma symptoms that require emergency care, including an unscheduled or urgent visit to a general practitioner, an ER visit, or a hospitalization in the last 12 months.One year later, 114 (22%) reported suboptimal control in the last 4 weeks; 114 (22%) had suffered an asthma attack in the last year; and 313 (61%) reported good control with no attacks. There were only 37 (7% of the total population) who had suboptimal asthma control and also suffered from an asthma attack in the last year. Suboptimal asthma control was associated with poor symptom control at baseline, wheezing triggered by allergens, colds, or exercise, a more intense treatment at baseline, history of preschool, persistent wheeze, and exposure to tobacco smoke. Increased incidence of asthma attacks was associated with previous episodes of severe wheezing and asthma attacks, younger age, and non-Swiss origin.The predictors of long term-suboptimal asthma differ from the predictors of asthma attacks. These 2 populations were distinct, and there were very few people who had both suboptimal asthma control and increased incidence of asthma attacks.Because these predictors were shown to be different for each population, different prediction scores for asthma control and asthma attacks may be needed to assess the future risk of these outcomes in children with asthma. Limitations include the reliance on family self-report. These findings also need to be explored in different patient populations.