Association between air pollution levels and drug sales for asthma and allergy in 63 million people in metropolitan France.

INTRODUCTION: Air pollution is known to have an impact on respiratory health. However, the assessment of this relationship is far from complete and is rarely extended to the country level. We used drug sales data, both Over-The-Counter (OTC) and prescription drugs, to assess exhaustively the impact of air pollution on asthma and allergy at the national level in France. METHODS: The WHO Anatomical Therapeutic Chemical (ATC) classification system was used to describe the distribution of sales of drugs of class R03 (Drugs for obstructive airways diseases, overall for asthma) and R06 (Antihistamines for systemic use). We performed a Quasi-Poisson regression model with a generalized additive model (GAM) to estimate the relationship (Relative Risks and 95% Confidence Interval) between drug sales and air pollutants, that is Particulate Matter with a diameter less than 2.5 micrometers (PM2.5) and less than 10 micrometers (PM10) and Nitrogen dioxide (NO2), as assessed using the high-resolution CHIMERE dispersion model. We designed unadjusted and adjusted single-pollutant models as well as two-pollutant models. RESULTS: PM2.5, PM10, and NO2 were significantly and positively associated with sales of R03 and R06 class drugs, after adjustment for potential confounders. Results were confirmed in the two-pollutant model for PM10 and NO2 but not for PM2.5. CONCLUSIONS: Our study confirms the presence of an association between major air pollutants and the sales of drugs against asthma and allergies. Further studies on larger databases and over several years are necessary to confirm and better understand these results.

Fine Particulate Matter Related to Multiple Sclerosis Relapse in Young Patients.

Objective: Particulate matter (PM) of aerodynamic diameter smaller than 10 µm (PM10) has been associated with multiple sclerosis (MS) relapse. However, the impact of smaller PM with a greater ability to penetrate human organism has never been assessed. We evaluated the impact of PM smaller than 2.5 µm (PM2.5) on the risk of MS relapse. Material and Methods: In a case-crossover study, we included 2,109 consecutive hospitalizations likely due to MS relapse in day hospital in 5 MS centers in the Paris area from January 2009 to December 2013. For each hospitalization, the natural logarithm of the average weekly PM2.5 concentrations (µg/m3) at the patient's residence address during each of the 6 weeks (week[0] to week[-5]) preceding admission was compared with the concentration during the previous week, using a conditional logistic regression adjusted on temperature, flu-like syndrome rate, pollen count, and holiday period. Results: PM2.5 average concentration during week[-3] was significantly associated with the risk of hospitalization for MS relapse [OR = 1.21 (CI 1.01;1.46)]. The association was stronger in patients younger than 30 years [OR=1.77 (CI 1.10; 2.83)]. Conclusion: Our study demonstrates an association between exposure to PM2.5 and MS relapse, particularly in young people.

Academically Produced Air Pollution Sensors for Personal Exposure Assessment: The Canarin Project.

The World Health Organization has estimated that air pollution is a major threat to health, causing approximately nine million premature deaths every year. Each individual has, over their lifetime, a unique exposure to air pollution through their habits, working and living conditions. Medical research requires dedicated tools to assess and understand individual exposure to air pollution in view of investigating its health effects. This paper presents portable sensors produced by the Canarin Project that provides accessible, real time personal exposure data to particulate matter. Our primary results demonstrate the use of portable sensors for the assessment of personal exposure to the different micro-environments attended by individuals, and for inspecting the short-term effects of air pollution through the example of sleep apnea. These findings underscore the necessity of obtaining contextual data in determining environmental exposure and give perspectives for the future of air pollution sensors dedicated to medical research.

Foetal exposure to heavy metals and risk of atopic diseases in early childhood.

BACKGROUND: Accumulating evidence suggests that in utero exposures can influence the development of the immune system and thus contribute to disease development. Studies investigating the association between prenatal exposures to heavy metals and atopic diseases, however, are scarce. METHODS: Children from the EDEN birth cohort were prospectively followed up using parental questionnaires with validated questions on asthma, allergic rhinitis, eczema, and food allergy symptoms. The questionnaires were administered every 4 months during the children's first year, and then every year until the age of 5, with a final survey at the age of 8. Serum concentrations of lead (Pb), cadmium (Cd), and manganese (Mn) were assessed in maternal blood samples collected during mid-pregnancy and in cord blood of 651 mother-children pairs. Hazard ratios (HR) for the incidence of each atopic disease in relation to the exposure to metals were calculated using Cox proportional hazard models. RESULTS: Levels of Cd in cord blood were associated with greater risk of asthma (hazard ratio [95% confidence interval] for upper vs lower quartile: 1.81 [1.00-3.29]), eczema (1.60 [1.09-2.35]), and food allergy (3.17 [1.36-7.38]), while Mn levels in maternal serum were associated with eczema (1.55 [1.05-2.28]). These associations were similar in males and females and were confirmed using log concentrations of metals as exposures. CONCLUSIONS: Our results support the hypothesis that fetal exposure to heavy metals may affect the development of asthma, eczema, and food allergy in childhood and suggest that timing of exposure in utero may have a role in these associations.