Ambient particulate air pollution and daily stock market returns and volatility in 47 cities worldwide.

We studied globally representative data to quantify how daily fine particulate matter (PM2.5) concentrations influence both daily stock market returns and volatility. Time-series analysis was applied on 47 city-level environmental and economic datasets and meta-analysis of the city-specific estimates was used to generate a global summary effect estimate. We found that, on average, a 10 µg/m3 increase in PM2.5 reduces same day returns by 1.2% (regression coefficient: - 0.012, 95% confidence interval: - 0.021, - 0.003) Based on a meta-regression, these associations are stronger in areas where the average PM2.5 concentrations are lower, the mean returns are higher, and where the local stock market capitalization is low. Our results suggest that a 10 µg/m3 increase in PM2.5 exposure increases stock market volatility by 0.2% (regression coefficient 0.002, 95% CI 0.000, 0.004), but the city-specific estimates were heterogeneous. Meta-regression analysis did not explain much of the between-city heterogeneity. Our results provide global evidence that short-term exposure to air pollution both reduces daily stock market returns and increases volatility.

Airborne pollen concentrations and daily mortality from respiratory and cardiovascular causes.

We conducted a time-series analysis of the relations between daily levels of allergenic pollen and mortality in the Helsinki Metropolitan Area with 153 378 deaths; 9742 from respiratory and 57 402 from cardiovascular causes. Daily (average) pollen counts of alder, birch, mugwort and grass were measured. In quasi-Poisson regression analysis, abundant alder pollen increased the risk of non-accidental deaths with an adjusted cumulative mortality rate ratio (acMRR) of 1.10 (95% CI 1.01-1.19) and of deaths from respiratory-diseases with acMRR of 1.78 (95% CI 1.19-2.65). Abundant mugwort pollen increased cardiovascular mortality (1.41, 1.02-1.95). These findings identify an important global public health problem.

Regular exercise improves asthma control in adults: A randomized controlled trial.

We conducted a randomized controlled trial to test the hypothesis that a 24-week exercise intervention improves asthma control in adults. Adults with mild or moderate asthma were randomly assigned to either the exercise intervention group (IG) or the reference group (RG). Participants in IG received an individualized exercising program, including aerobic exercise at least three times a week for ≥30 minutes, muscle training, and stretching. The primary outcome was asthma control, measured by Asthma Control Test (ACT), asthma-related symptoms, and peak expiratory flow (PEF) variability. We estimated the risk (i.e. probability) of improvement in asthma control and the risk difference (RD) between IG and RG. Of 131 subjects (67 IG/64 RG) entered, 105 subjects (51/54) completed the trial (80%), and 89 (44/45) were analysed (68%). The ACT became better among 26 (62%) participants in IG and among 17 (39%) participants in RG. The effect of intervention on improving asthma control was 23% (RD = 0.23, 95% CI 0.027-0.438; P = 0.0320). The intervention also reduced shortness of breath by 30.1% (RD = 0.301, 95% CI 0.109-0.492; P = 0.003). The change in PEF variability was similar in both groups. Regular exercise improves asthma control measured by the ACT, while has little effect on PEF variability.