Land Use and Children's Respiratory Symptoms in Connecticut

Previous research showed that air pollution affects respiratory symptoms in children, but some study designs are faced with the challenge of obtaining exposure for participants far from an air pollution monitor, especially if the study covers large area. Numerous studies have applied land-use regression modeling for a variety of purposes. We applied this methodology to use developed land use as an indicator of air pollutant levels to investigate the relationship between developed land-use and wheeze symptoms in 761 children in Connecticut from 1996 to 1998. Study subjects were infants with respiratory siblings from a cohort study conducted by the Yale Center for Perinatal, Pediatric and Environmental Epidemiology. Mothers recorded infants' wheeze symptoms from birth to age 12 months. Land-use data was obtained from satellite imagery, LANDSAT, using supervised classification. The fraction of land that was developed within a 750m buffer of the subject's residence was calculated. Additional buffer sizes were explored as sensitivity analysis. Logistic regression was conducted, adjusted by gender, family asthma history, and socio-economic status. Higher fraction of developed land was associated with increased risk of wheeze symptoms. A 20% increment in developed land use within the 750m buffer was associated with 1.14 times (95% CI 1.01-1.29) increased risk of wheeze symptoms. As sensitivity analysis, logistic analysis with quartile index of developed land use was conducted. The 4th quartile show significant effect compared to 1st quartile, OR=1.70 (1.06-2.71). These results suggest that residence in a developed area might adversely affect infants' respiratory health.