Elevated particle number concentrations induce immediate changes in heart rate variability: A panel study in individuals with impaired glucose metabolism or diabetes

Background: the health effects of short-term exposure to ambient ultrafine particles in micro-environments are still under investigation. methods: sixty-four individuals with type 2 diabetes and impaired glucose tolerance recorded ambulatory electrocardiograms over five to six hours on 191 occasions in a panel study in augsburg,germany. personal exposure to particle number concentrations (pnc) was monitored for each individual on 5-minute basis concurrently and particulate matter with an aerodynamic diameter < 2.5 μm (pm2.5) was acquired from a central monitoring site on an hourly basis. results: more than 11,000 5-minute intervals were available for heart rate and measures of heart rate variability including sdnn (standard deviation of nn intervals). a concurrent decrease in 5-minute sdnn of -0.56% (95% confidence limits (ci): -1.02%; -0.09%) and a 5-minute delayed increase in heart rate of 0.23 % (95% ci: 0.11%; 0.36%) was observed with an increase in personal pnc of 16,000 per cm3 in additive mixed models. models evaluating the association of concurrent 5-minute personal pnc and of 1-hour pm2.5 showed independent effects on sdnn. conclusion: the data suggest that freshly emitted ultrafine particles and aged fine particulate matter are both associated with changes in cardiac function in individuals with type 2 diabetes and impaired glucose tolerance in urban areas. © 2015 peters et al.