Long-term exposure to traffic-related air pollution has been associated with increased risk for insulin resistance in children….
The theory behind this correlation stems from the potent oxidizing effects that are caused by air pollutants. In turn, it is believed that this oxidative stress plays a role in insulin resistance. In addition, studies have reported that increases in particulate matter and nitrogen dioxide can lead to elevated inflammatory biomarkers, another plausible mechanism for insulin resistance.
The recent German study included 397 10-year-old children from two prospective birth cohort studies, GINIplus and LISAplus. Fasting blood samples were collected from each of the children. Individual- level exposures to traffic-related air pollutants at their birth address were estimated through land use regression models. The study analyzed the association between air pollution and HOMA of insulin resistance (HOMA-IR) using a linear model adjusted for a number of covariates including birthweight, pubertal status, BMI, and second-hand smoke exposure.
Results revealed that in all crude and adjusted models, levels of insulin resistance were greater in children with higher exposure to air pollution. Specifically, insulin resistance increased by 17% and 18.7% for every 2 standard deviations increase in ambient NO2 and particulate matter </10micrometer in diameter, respectively. Proximity to the nearest major road increased insulin resistance by 7.2% per 500 meters.
The 15 year follow-up of both cohorts is still ongoing and the authors plan to investigate how their findings translate into older age during or after puberty.
Long-term exposure to traffic-related air pollution and insulin resistance in children: results from the GINIplus and LISAplus birth cohorts. Diabetologia, 2013 DOI: 10.1007/s00125-013-2925-x