Residential air pollution does not modify the positive association between physical activity and lung function in current smokers in the ECRHS study.

BACKGROUND: Very few studies have examined whether a long-term beneficial effect of physical activity on lung function can be influenced by living in polluted urban areas. OBJECTIVE: We assessed whether annual average residential concentrations of nitrogen dioxide (NO2) and particulate matter with aerodynamic diameters < 2.5 µm (PM2.5) and <10 µm (PM10) modify the effect of physical activity on lung function among never- (N = 2801) and current (N = 1719) smokers in the multi-center European Community Respiratory Health Survey. METHODS: Associations between repeated assessments (at 27-57 and 39-67 years) of being physically active (physical activity: ≥2 times and ≥1 h per week) and forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were evaluated using adjusted mixed linear regression models. Models were conducted separately for never- and current smokers and stratified by residential long-term NO2, PM2.5 mass and PM10 mass concentrations (≤75th percentile (low/medium) versus >75th percentile (high)). RESULTS: Among current smokers, physical activity and lung function were positively associated regardless of air pollution levels. Among never-smokers, physical activity was associated with lung function in areas with low/medium NO2, PM2.5 mass and PM10 mass concentrations (e.g. mean difference in FVC between active and non-active subjects was 43.0 mL (13.6, 72.5), 49.5 mL (20.1, 78.8) and 49.7 mL (18.6, 80.7), respectively), but these associations were attenuated in high air pollution areas. Only the interaction term of physical activity and PM10 mass for FEV1 among never-smokers was significant (p-value = 0.03). CONCLUSIONS: Physical activity has beneficial effects on adult lung function in current smokers, irrespective of residential air pollution levels in Western Europe. Trends among never-smokers living in high air pollution areas are less clear.

Agreement in reporting of asthma by parents or offspring - the RHINESSA generation study.

BACKGROUND: Self-report questionnaires are commonly used in epidemiology, but may be susceptible to misclassification, especially if answers are given on behalf of others, e.g. children or parents. The aim was to determine agreement and analyse predictors of disagreement in parents' reports of offspring asthma, and in offspring reports of parents' asthma. METHODS: In the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) generation study, 6752 offspring (age range 18-51 years) and their parents (age range 39-66 years) reported their own and each other's asthma status. Agreement between asthma reports from offspring and parents was determined by calculating sensitivity, specificity, positive and negative predictive value and Cohen's kappa. The participants' own answers regarding themselves were defined as the gold standard. To investigate predictors for disagreement logistic regression analyses were performed to obtain odds ratios (OR) with 95% confidence intervals (CI) for sex, smoking status, education, comorbidity and severity of asthma. RESULTS: Agreement was good for parental report of offspring early onset asthma (< 10 years, Cohen's kappa 0.72) and moderate for offspring later onset asthma (Cohen's kappa 0.46). Specificity was 0.99 for both, and sensitivity was 0.68 and 0.36, respectively. For offspring report of maternal and paternal asthma the agreement was good (Cohen's kappa 0.69 and 0.68), specificity was 0.96 and 0.97, and sensitivity was 0.72 and 0.68, respectively. The positive predictive value (PPV) was lowest for offspring report of maternal asthma (0.75), and highest for parents' report of early onset asthma in the offspring (0.83). The negative predictive value (NPV) was high for all four groups (0.94-0.97). In multivariate analyses current smokers (OR = 1.46 [95% CI 1.05, 2.02]) and fathers (OR = 1.31 [95% CI 1.08, 1.59]) were more likely to report offspring asthma incorrectly. Offspring wheeze was associated with reporting parental asthma incorrectly (OR = 1.60 [95% CI 1.21, 2.11]), both under- and over reporting. CONCLUSIONS: Asthma reports across generations show moderate to good agreement, making information from other generations a useful tool in the absence of direct reports.