SmokeHaz: Systematic Reviews and Meta-analyses of the Effects of Smoking on Respiratory Health.

BACKGROUND: Smoking tobacco increases the risk of respiratory disease in adults and children, but communicating the magnitude of these effects in a scientific manner that is accessible and usable by the public and policymakers presents a challenge. We have therefore summarized scientific data on the impact of smoking on respiratory diseases to provide the content for a unique resource, SmokeHaz. METHODS: We conducted systematic reviews and meta-analyses of longitudinal studies (published to 2013) identified from electronic databases, gray literature, and experts. Random effect meta-analyses were used to pool the findings. RESULTS: We included 216 articles. Among adult smokers, we confirmed substantially increased risks of lung cancer (risk ratio (RR), 10.92; 95% CI, 8.28-14.40; 34 studies), COPD (RR, 4.01; 95% CI, 3.18-5.05; 22 studies), and asthma (RR, 1.61; 95% CI, 1.07-2.42; eight studies). Exposure to passive smoke significantly increased the risk of lung cancer in adult nonsmokers and increased the risks of asthma, wheeze, lower respiratory infections, and reduced lung function in children. Smoking significantly increased the risk of sleep apnea and asthma exacerbations in adult and pregnant populations, and active and passive smoking increased the risk of tuberculosis. CONCLUSIONS: These findings have been translated into easily digestible content and published on the SmokeHaz website.

Airway eosinophilia in children with severe asthma: predictive values of noninvasive tests.

RATIONALE: Children with severe asthma experience persistent symptoms despite maximal conventional treatment. Fraction of exhaled nitric oxide (Fe(NO)) and sputum eosinophils are used as markers of airway inflammation to guide treatment with steroids, but no data are available on how reliable they are in predicting airway eosinophilia assessed bronchoscopically in these children. OBJECTIVES: To determine how Fe(NO) and sputum eosinophils predict airway eosinophilia measured in both bronchoalveolar lavage (BAL) and endobronchial biopsy. METHODS: Twenty-seven children with moderate to severe persistent asthma attempted measurement of Fe(NO) and sputum eosinophils, followed by bronchoscopy, BAL, and endobronchial biopsy within 24 h. MAIN RESULTS: Significant correlations were found between eosinophils in sputum and both BAL eosinophils (n = 20, r = 0.45, p = 0.045) and Fe(NO) (n = 23, r = 0.42, p = 0.049). The relationship between Fe(NO) and BAL eosinophils was also significant with a stronger correlation (n = 24, r = 0.54, p = 0.006). The positive predictive value (PPV) for increased sputum eosinophil percentage (> 2.5%) to detect elevated eosinophils in BAL (> 1.19%) was 75%; the negative predictive value (NPV) was 63%. All patients with both increased sputum eosinophils and an elevated Fe(NO) value (> 23 ppb) had elevated eosinophils in BAL (PPV, 100%); the NPV of these two markers was 65%. Eight of nine patients without any sputum eosinophils had normal subepithelial eosinophil numbers (< 1.2%; NPV, 89%). However, the PPV of any sputum eosinophils for increased subepithelial eosinophilia was only 36.4%. CONCLUSIONS: There was moderate agreement between both Fe(NO) and sputum eosinophils and BAL eosinophils. There was good NPV, but only poor PPV for these markers for mucosal eosinophilia.

Histopathologic subsets of fibrosing alveolitis in patients with systemic sclerosis and their relationship to outcome.

Fibrosing alveolitis associated with systemic sclerosis (FASSc) has a better prognosis than idiopathic pulmonary fibrosis. In view of recent reports that idiopathic nonspecific interstitial pneumonia (NSIP) has a better prognosis than idiopathic usual interstitial pneumonia (UIP), we classified histologic appearances of surgical lung biopsies performed in 80 patients with FASSc. NSIP (n = 62, 77.5%), subcategorized as cellular NSIP (n = 15) and fibrotic NSIP (n = 47) was much more prevalent than UIP (n = 6), end-stage lung disease (ESL, n = 6), or other patterns (n = 6). There were 25 deaths (NSIP 16/62, 26%; UIP/ESL 6/12, 50%). Five-year survival differed little between NSIP (91%) and UIP/ESL (82%); mortality was associated with lower initial carbon monoxide diffusing capacity (DL(CO)) and FVC levels (p = 0.004 and p = 0.007, respectively). Survival and serial FVC and DL(CO) trends did not differ between cellular and fibrotic NSIP. Increased mortality in NSIP was associated with lower initial DL(CO) levels (p = 0.04), higher BAL eosinophil levels (p = 0.03), and deterioration in DL(CO) levels during the next 3 years (p < 0.005). We conclude that NSIP is the histopathologic pattern in most patients with FASSc. However, outcome is linked more strongly to disease severity at presentation and serial DL(CO) trends than to histopathologic findings.