Department of Epidemiology Lazio Regional Health Service - Italy
ISEE Young 2014
October 20-21, 2014
Long-term exposure to polycyclic aromatic hydrocarbons (PAH) and incidence of stroke in the Rome Longitudinal Study,
2008-2012 - the EXPAH project
Chiara Badaloni
1, Giulia Cesaroni
1, Massimo Stafoggia
1, Claudio Gariazzo
2, Francesco Forastiere1, EXPAH Study Group.
1. Department of Epidemiology, Regional Health Service, Lazio Region, Rome, Italy
Background and aims
Particulate air pollution has been classified as carcinogenic to humans by the International Agency for Research on Cancer. The evidence of the association between long-term air pollution exposure and incidence of stroke still debated.
The objective of this study is to investigate the association of PM2.5 and polycyclic aromatic hydrocarbons (PAHs), (4 congeners:
Benzo[a]Pyrene (BaP), Benzo[b]fluoranthene, Benzo[k]fluoranthene, Indeno Pyrene benzo[a]pyrene), with incidence of stroke.
Reference: Chiara Badaloni
Results
There were 12,865 new cases of stroke. There was evidence of association between exposure to all pollutants and incidence of stroke:
a 7% higher risk for 1.3 ng/m3 increase in PAHs and a 10% higher risk for each 5 µg/m3 increase in PM2.5.
Methods
The Rome Longitudinal Study (*) was used, selecting subjects aged 40 years or more at Jan 2008 and following them till Dec 2012. Residential exposure to PAHs and PM2.5 was assigned by means of a chemical transport model (1 km resolution), using measurements collected during 2011-12.
We selected new stroke cases using the protocol adopted in the ESCAPE project (*) (hospitalizations with principal diagnosis of stroke, ICD-9- CM: 431, 433.x1, 434, 436, and death certificates with underlying cause of death with ICD-9 codes 431-436).
We considered subjects who had not been admitted to hospital for cerebrovascular disease in the 28 days before the death, nor for any cause in the two days before the death.
Cox regression models were used to evaluate the association between pollutants and stroke adjusting for several individual and contextual factors.
Table 1. Description of the study population and exposure
Conclusions
We found strong evidence of association between long-term exposure to PAHs and PM2.5 and incidence of stroke.
Table 2. Descriptive statistics of environmental variables in Rome population
Table 3. Association between air pollution exposure and incidence of stroke. Rome 2008-2012
2. INAIL Research center, Monteporzio Catone, Rome, Italy
Figure 1. Chemical Transport models 1km resolution of PM2.5 and PAHs
Funding
Population Exposure to PAHs (EXPAH) project life+ (Life09 ENV/IT/000082)
References
1. Long-Term Exposure to Urban Air Pollution and Mortality in a Cohort of More than a Million Adults in Rome. Giulia Cesaroni, et al. Environ
Health Perspect. 2013 Mar;121(3):324-31. Epub 2013 Jan 7.
2. Long-Term Exposure to Ambient Air Pollution and Incidence of
Cerebrovascular Events: Results from 11 European Cohorts within the ESCAPE Project. Massimo Stafoggia et al. Environ Health Perspect.
2014 Sep;122(9):919-25. Epub 2014 May 15.
HR * HR * HR *
Incidence of stroke (12,865 cases)
PAH 0.93 0.88 0.99 1.05 0.99 1.12 1.07 1.00 1.13 PM2.5 1.03 0.97 1.10 1.10 1.03 1.17 1.10 1.04 1.18
95%CI 95%CI 95%CI
Crude Hazard Ratios
Adjusted Hazard Ratios*
Adjusted Hazard Ratios**
Gender
Men 449,624 2.14 0.40 19.9 1.5
Women 564,262 2.16 0.39 20.0 1.5
Age classat baseline
40-59 498,365 2.12 0.40 19.9 1.5
60-79 410,952 2.16 0.39 20.0 1.5
80-99 104,569 2.24 0.36 20.2 1.3
Level of education
High 174,381 2.26 0.36 20.2 1.3
Medium 595,923 2.14 0.39 19.9 1.5
Low 243,582 2.10 0.40 19.9 1.6
Area-based socioeconomic position
Vey high 208,165 2.30 0.29 20.3 1.0
High 211,505 2.25 0.36 20.2 1.4
Medium 203,596 2.18 0.38 20.0 1.5
Low 200,068 2.03 0.43 19.7 1.7
Verylow 189,783 1.98 0.40 19.5 1.6
PAHs
(Mean, sd)
PM2.5 (Mean, sd) N
HR*: adjusted for occupation, education, marital status, area-based SEP, stratified by sex, with age as time-scale
HR**: adjusted for occupation, education, marital status, area-based SEP, income, diabetes, hypertension, stratified by sex, with age as time-scale Fixed increments: 5 ug/m3 for PM2.5; 1.3 ng/m3 for PAHs
min 5th 25th 50th 75th 95th max
PAH 1,013,886 2.15 0.39 0.52 1.40 1.91 2.23 2.43 2.70 2.76 0.52 PM2.5 1,013,886 19.94 1.48 13.37 16.69 19.23 20.32 21.07 21.57 22.84 1.84 Models based on measurements taken from 01/06/2011 to 31/05/2012
Variable No. Subjects Mean SD Percentiles
IQR
