PURA Urban vs. Rural Asthma (PURA)
The PURA study, which took place from 2009-2010, was a population-based study of 1,441 adolescents ages 13-15 years living in two cities in Peru with differing levels of urbanization. 725 adolescents were recruited in Lima, the capital city of Peru, where over 1/3 of the population resides and is highly urbanized; 716 were from Tumbes, a less urbanized, coastal city near the border with Ecuador. We administered a questionnaire on asthma symptoms, environmental exposures, and socio-demographics, and all participants underwent pre- and post- bronchodilator spirometry, skin allergy testing, and exhaled nitric oxide testing. Finally, we obtained blood samples for hematocrit, total IgE levels, vitamin D levels and DNA in all participants and measured indoor particulate matter concentrations for 48 hours in a random subset of 70-100 households at each site.