ABSTRACT
BACKGROUND: Preschool rhinovirus (RV) wheezing illnesses predict an increased risk of childhood asthma; however, it is not clear how specific viral illnesses in early life relate to lung function later on in childhood. OBJECTIVE: To determine the relationship of virus-specific wheezing illnesses and lung function in a longitudinal cohort of children at risk for asthma. METHODS: Two hundred thirty-eight children were followed prospectively from birth to 8 years of age. Early life viral wheezing respiratory illnesses were assessed by using standard techniques, and lung function was assessed annually by using spirometry and impulse oscillometry. The relationships of these virus-specific wheezing illnesses and lung function were assessed by using mixed-effect linear regression. RESULTS: Children with RV wheezing illness demonstrated significantly decreased spirometry values, FEV(1) (P = .001), FEV(0.5) (P < .001), FEF(25-75) (P < .001), and also had abnormal impulse oscillometry measures--more negative reactance at 5 Hz (P < .001)--compared with those who did not wheeze with RV. Children who wheezed with respiratory syncytial virus or other viral illnesses did not have any significant differences in spirometric or impulse oscillometry indices when compared with children who did not. Children diagnosed with asthma at ages 6 or 8 years had significantly decreased FEF(25-75) (P = .05) compared with children without asthma. CONCLUSION: Among outpatient viral wheezing illnesses in early childhood, those caused by RV infections are the most significant predictors of decreased lung function up to age 8 years in a high-risk birth cohort. Whether low lung function is a cause and/or effect of RV wheezing illnesses is yet to be determined.
Subject(s)
Asthma/diagnosis , Picornaviridae Infections/complications , Respiratory Sounds/etiology , Rhinovirus/pathogenicity , Asthma/etiology , Asthma/physiopathology , Child , Child, Preschool , Cohort Studies , Female , Humans , Longitudinal Studies , Lung/physiopathology , Male , Oscillometry , Picornaviridae Infections/virology , Respiratory Function Tests , Risk , SpirometrySubject(s)
Breathing Exercises , Neuromuscular Diseases/complications , Neuromuscular Diseases/physiopathology , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy , Abdominal Muscles/physiopathology , Child , Humans , Muscle Contraction , Muscular Dystrophies/complications , Respiratory Function Tests , Respiratory Insufficiency/physiopathology , Respiratory Muscles/physiopathology , Respiratory Therapy , Scoliosis/complications , Sleep Apnea Syndromes/etiology , Sleep Apnea Syndromes/physiopathologyABSTRACT
PURPOSE OF REVIEW: The prevalence of asthma is increasing in many parts of the world, particularly in developed countries. The present review focuses on recent literature regarding asthma prevention in childhood. RECENT FINDINGS: Several environmental exposures in infancy or early childhood are associated with reduced prevalence of asthma, but the mechanisms leading to these associations remain unknown. Recent studies have demonstrated limited success in the prevention of asthma or asthma symptoms with the use of asthma medications, once the therapy is discontinued. Immunotherapy offers another strategy for asthma prevention, and groups treated with this intervention have demonstrated reduced atopy and asthma. Several multi-interventional trials have demonstrated a reduced asthma symptom burden but have not demonstrated significant differences in objective measures such as lung function or bronchial hyper-responsiveness between intervention groups. SUMMARY: The most promising asthma prevention strategies to date have been those that use a multi-interventional approach employing both dietary and environmental manipulations. More research is needed to assess the long-term follow-up of multi-interventional trials and to evaluate novel intervention strategies in the primary or secondary prevention of asthma in childhood.
