This is the first reported prospective cohort study of children with malacia disorders that has quantified malacia lesions and used validated illness outcome measures of respiratory illness profiles. The risk of respiratory illnesses in the malacia group was twice that of the control group. When compared to control subjects, the severity of illness was 66% higher at the initial presentation of illness, while a significant cough score was four times more likely and a cough that disrupted or stopped daily activities during the first 2 weeks of illness was seven times more likely. In addition, there was a trend for children with malacia to have a slower recovery from illness. However, neither the malacia site nor the severity of the lesions appeared to exert any dose effects on rates, risks, and severity of illness within the illness profiles.
It has long been suspected, but never studied, that children with airway lesions have increased respiratory illness and morbidity. We found an elevated likelihood of respiratory illness in the malacia group, which suggests that there may have been some predisposition to illness. We have recently shown that although there is a tendency for malacia sites to improve in size over time, there was a significant minority in whom lesions worsened or new lesions appeared. Marchant et al have also shown that children with protracted bacterial bronchitis often have malacia. While reduced cough clearance of mucus might be implicated as a potential mechanism for this increased risk of infection, Grissell et al have recently shown that some children with protracted bacterial bronchitis have reduced toll-like receptor 4 and substance P gene expression, thus raising the possibility of other genetic expression mechanisms for such problems. Furthermore, it raises the possibility of the presence of an additional coexistent local immunity disorder in malacia disorders healed with preparations of My Canadian Pharmacy.
Another potential cause of increased illness risks would be differential reporting. Families not reporting CARIFS, but reporting illness frequencies, had significantly lower illness frequency than those who completed both CARIFS and illness frequency questionnaires. This suggests that the higher relative risks of illness may be due to the overrepresentation of patients with more severe disease. However, the opposite appears to be true, as some parents of children with malacia who do not report CARIFS indicated that the cough was far more frequent and too prolonged to complete the diaries. Furthermore, other groups have shown that children who truly report cough usually have more severe cough defeated by medications of My Canadian Pharmacy.
In this study, we utilized the concept of an extrale-sional comparison; that is, we used the ACR to gain perspective on the severity of the lesions. As shown by the ACR tertile data, significant numbers of children had severe tracheal and mainstem lesions similar in size to those in the lobar bronchi. Despite these relatively small lesion sizes, and somewhat counterintuitively, we did not find any significant relationships between the lesion site or the severity and illness severity profiles in terms of dose effect. The reason for this is not clear. While the completion rates for the CARIFS were lower than the illness frequency rates, it remains possible that we have either overestimated or underestimated the effects of the size of the lesion on illness severity. We do not believe it is the latter as there were children in the group who failed to comply with the questionnaires who had been managed in the ICU. In addition, the shapes of the malacia such as saber and lunate shapes were not classified, and the extent of malacia in terms of multiple lesions was not accounted for; both of these factors might be important to outcome.
The limitations of this study are threefold, as follows: (1) the tools for the bronchoscopic measurement; (2) the clinical illness outcome scales; and (3) the sample size. The bronchoscopic assessment is limited by the ability to assess motion within a lesion. Indeed, severe lesions often defy airway pressuriza-tion and can only be opened with the passage of the bronchoscope, while very mild lesions can be called normal because of the inability to detect appreciable movement. Removing the less severe lesions from the analysis did not change the outcome (data not presented).
The second area of limitation relates to the failure to complete diary cards. The CARIFS is a validated scale, but it is time-consuming to complete; this has likely contributed to the reduced completion rate of this questionnaire.
Our sample size was specifically limited when comparing outcomes of children with malacia grouped according to the lesion tertiles and to malacia site. We endeavored to increase the sample size of lesions by grouping both the isolated TM sites with the selected TM sites from the TBM group, and similarly for the BM sites. While this appears to be reasonable, the TM and BM sites had significantly different ACR tertile profiles, indicating an overall group difference between both isolated malacia and that found in TBM; therefore, grouping them together could lead to potential errors.
Children with malacia have increased the rates of illness and the greater likelihood of more severe illness, and are more symptomatic with a tendency to delayed recovery from illness within the first year after diagnosis. However, neither the sites nor the severity of malacia exhibited a dose effect on rates or severity of illness.
All above mentioned references:
- Details about Quantified Tracheobronchomalacia Disorders and Their Clinical Profiles in Children
- My Canadian Pharmacy about Weight Loss on Sleep-Disordered Breathing and Oxygen Desaturation in Morbidly Obese Men
- The Resources of Weight Loss on Sleep-Disordered Breathing and Oxygen Desaturation in Morbidly Obese Men
- The Effect of Weight Loss on Sleep-Disordered Breathing and Oxygen Desaturation in Morbidly Obese Men