Background: Tracheobronchomalacia (TBM) disorders in children have never been studied using quantified measurements and validated clinical outcome measures. The objectives of the study were to prospectively examine the relationship between malacia lesions and their respiratory illness profiles.
Methods: The site of malacia lesions (eg, tracheomalacia, TBM, and bronchomalacia) were determined, measured, and related to the respective cricoid (ie, airway/cricoid ratio) using the color histogram mode technique. These children and normal control subjects were followed up for 12 months with their respiratory illness profiles determined using the Canadian Acute Respiratory Illness Scale (CARIFS) and cough diary scores.
Measurements: Outcome measures were respiratory illness frequency (> 12 months), severity score (day-1 CARIFS score), and significant cough interfering with daily activity (score of >or= 3) and illness resolution (time to return to a quarter of CARIFS day 1 score).
Results: The group of 116 children were composed of patients with malacia (n = 81) and control subjects (n = 35). The median age of the group was 2.1 years (age range, 0.2 to 17.3 years). The adjusted relative risk of illness frequency was 2.1 (95% confidence interval [CI], 1.3 to 3.4), and of significant cough was 7.2 (95% CI, 1.01 to 27.22) for the malacia group while CARIFS day 1 score was 1.66 (95% CI, 1.1 to 2.56) compared to control subjects. Illness resolution rates at day 14 in the malacia group trended 25% slower than those for control subjects. Malacia type and severity of lesions were not associated with increased rates of illness or worse clinical profiles.
Conclusion: Children with malacia have an increased likelihood of respiratory illness frequency, severity, significant cough, and tendency for delayed recovery. However, neither the site nor the severity of malacia exhibited any significant dose effect on respiratory illness profiles.