Individual effect modifiers of dust exposure effect on cardiovascular morbidity

Background: High concentrations of particulate matter (PM) air pollution have been associated with death and hospital admissions due to cardiovascular morbidity. However, it is not clear a) whether high levels of non-anthropogenic PM from dust storms constitute a health risk; and b) whether these health risks are exacerbated in a particular demographic. Methods This study comprised all patients above 18 years old admitted to Soroka University Medical Center (1000 bed tertiary hospital, Be'er-Sheva, Israel, 2001-2010) with a primary diagnosis of acute coronary syndrome (ACS). Data on meteorological parameters and PM10 (particulate matter <10 μm in aerodiameter) were obtained from monitoring stations in the city of Be'er-Sheva. Data were analyzed using a case crossover analysis to examine the effect of dust exposure on hospitalization due to ACS and the interaction with co-morbidities and demographic factors. Results: There were 16,734 hospitalizations due to ACS during the study period. The estimated odds of hospitalization due to ACS was significantly associated with PM10 during non dust storm days at the same day of the exposure (lag0); OR = 1.014 (95%CI 1.001-1.027) for a 10 μg/m³ increase, while a delayed response (lag1) was found during the dust storm days; OR = 1.007 (95%CI 1.002-1.012). The effect size for the dust exposure association was larger for older (above the age of 65), female or Bedouin patients. Conclusions Exposure to non-anthropogenic PM is associated with cardiovascular morbidity. Health risk associated dust exposure is gender and age specific with older women and Bedouin patients being the most vulnerable groups.