Asthma? Furry Pets!!

ABSTRACT: 
Recurrent bronchial obstructions and asthma are commonly encountered after hospital admission for wheezing. Some of these children do not go on to develop asthma while others do. The cause of wheezing in young children can be from narrow airways obstructed by mucus and edema during respiratory infection or in atopic children, eosinophilic inflammation typical of asthma in their airways. This is the first study to examine long-term outcome after early anti-inflammatory therapy in wheezing infants. A few reports exist concerning the predictive value of allergic sensitization in the development of asthma after infantile wheezing. This study aimed to evaluate the 3-year outcome after hospital admission for wheezing in infancy.

The authors determined that early anti-inflammatory therapy (nebulized cromolyn sodium or budesonide) had no influence on the occurrence of asthma or on the need for maintenance medication 3 years later. There were some factors noted that predicted the presence of asthma 3 years after the primary hospital admission for wheezing. Children who were more that 12 months of age at study entry increased significantly the occurrence of asthma. Positive skin prick test (SPT) 8 months after the initial episode of wheezing was also a predictor of asthma. SPT reactions to indoor allergens, especially dog or cat dander were very prognostic; all patients who tested positive for reactions to these substances developed asthma. There was no significant association between having a furred pet at home during infancy and SPT reactivity to animal dander.

Identification of respiratory syncytial virus (RSV) at entry as well as the presence of a furred pet at home during infancy actually decreased the risk of later asthma. Only 22% of patients with RSV infection on entry, compared to 61% of patients without RSV, developed asthma by the age of 4 years. History of wheezing and atopic dermatitis on study entry were also significant predictors of asthma. There was no predictive value to family history of atopy or asthma, male sex, passive smoking during pregnancy or in infancy, number of siblings, living area in early childhood, and elevated IgE serum.

Children with asthma more often had current atopic manifestations like atopic eczema, allergic rhinitis and allergic conjunctivitis than their non-asthmatic counterparts. Current reactivity to outdoor allergens was present in one third of asthma patients and only in one tenth of those without.

COMMENTS: 
This study, a prospective 3-year follow-up in infants, shows that early anti-inflammatory therapy for 4 months has no bearing on whether or not the children will develop asthma 3 years later. The result that early medication did not prevent the development of asthma concurs with 2 recent studies on wheezing infants.

It is interesting that the wheezing patients in this study who had RSV infection had a much better prognosis than those patients without the infection. This finding contradicts a prior study that found that RSV infection was a major risk factor for later asthma. It would seem that early childhood wheezing with other than RSV etiology has the highest risk for later asthma. The authors of this study hypothesized that the outcome after infantile wheezing is partly dependent on the invasiveness of the causative virus. Invasive viruses like RSV are able to induce wheezing and transient but reversible impairment in pulmonary function also in children with no susceptibility to asthma.

SPT sensitivity to indoor allergens is strongly associated with the development of later asthma in wheezing infants. On average positive SPT predicted a 10-fold risk for the development of asthma compared to those with a negative result. There was no significant negative association noted between early pet contact and SPT reactivity to animal dander. A surprise finding in this study, though, was that furred pet exposure in early life seemed to protect children from the development of asthma , a correlation that has never been reported in previous studies with wheezing infants however parallel results have been reported recently in school-aged children.

This study’s main weakness was that the follow-up study was not blinded; the investigators knew the clinical data of each patient when making decisions at follow-up visits. The study was also hospital-based and thus offers only information about the severe form of wheezing in early childhood that necessitated a hospital visit.

Chiropractors are asked by their patients to offer opinions on the use of medication for childhood ailments. They also offer treatment alternatives to medication for conditions asthma such as nutritional agents and dietary advice. Responsible chiropractors will know the natural course of a condition and make recommendations as to whether or not chiropractic can alter that course positively or if standard medical treatment would prove superior. In this case, if the standard medical treatment is anti-inflammatory therapy for 4 months given to infants with a presentation of wheezing, any other non-invasive procedure would likely be of equal or greater benefit.