Associations of short-term exposure to ambient air pollutants with emergency ambulance calls for the exacerbation of essential arterial hypertension.

We investigated the association between daily emergency ambulance calls (EAC) for elevated blood pressure that occurred during the time intervals of 8:00-13:59, 14:00-21:59, and 22:00-7:59, and exposure to CO, PM10 , and ozone. We used Poisson regression to explore the association between the risk of EAC and short-term variation of pollutants, adjusting for seasonality and weather variables. Before noon, the risk was associated with an interquartile range (IQR) (7.9 μg/m3 ) increase in PM10 at lag 2-4 days below the median (RR = 1.08, p = 0.031) and with an IQR (0.146 mg/m3 ) increase in CO at lag 6-7 below the median (RR = 1.05, p = 0.028). During 14:00-21:59, the risk was associated with an IQR (18.8 μg/m3 ) increase in PM10 on the previous day below the median (RR = 1.04, p = 0.031). At night, EAC were negatively affected by lower O3 (lag 0-2) below the median (per IQR decrease RR = 1.10, p = 0.018) and a higher PM10 at lag 0-1 above the median for the elderly (RR = 1.07, p = 0.030).