nitrogen-dioxide and Subarachnoid-Hemorrhage

The relationship between air pollutants, including fine particles (particulate matter [PM] < 10 μm and < 2.5 μm), and aneurysmal subarachnoid hemorrhage (SAH) has been inadequately studied, and the results remain inconclusive. In this study, we attempted to investigate the relationship between air pollutant levels and aneurysmal SAH.. Ninety-two patients diagnosed with aneurysmal SAH were retrospectively included in the study. Medical records were reviewed, and levels of pollutants, including those of sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), carbon monoxide (CO), and PM with an aerodynamic diameter < 10 and 2.5 μm (PM10 and PM2.5), were collected from the open-source Air Korea website for a period of 4 days. Independent t-tests were conducted to identify the difference in the pollutant levels between the data obtained on the day of aneurysm rupture (D-0) and the other 3 days (D-7, D-2, and D-1).. A majority (40.2%) of the patients experienced aneurysm rupture during the fall season when the mean daily pollutant levels were 0.004 ± 0.001 (ppm, SO2), 0.517 ± 0.218 (ppm, CO), 0.02056 ± 0.012 (ppm, O3), 0.02628 ± 0.015 (ppm, NO2), 36.36957 ± 24.538 (μg/m3, PM10), and 19.75581 ± 13.494 (μg/m3, PM2.5), respectively. The level of NO2 was significantly higher on the day of aneurysm rupture (P = .035) than on the other days, while the levels of CO and O3 were nonsignificantly higher (P = .081, P = .055, respectively) on the day of aneurysm rupture than on the other days. There was no significant differences in the PM levels between the 4 days.. A relationship between PM levels and aneurysm rupture was not identified. Only the levels of classic air pollutant (CO, O3, and NO2) were higher on the aneurysm rupture day than on the other days.

Topics: Air Pollutants; Aneurysm; Environmental Pollutants; Humans; Nitrogen Dioxide; Ozone; Particulate Matter; Retrospective Studies; Subarachnoid Hemorrhage; Sulfur Dioxide

Apart from the conventional risk factors, cerebro-cardiovascular disease (CVD) are also reported to be associated with air pollution, thus lowering the level of exposure might contribute in prevention activities to reduce the associated adverse outcomes. Though few studies conducted in Japan have reported on the CVD mortality but none have explored the effect of air pollutant exposure on the acute case-fatality of CVD. We investigated the effects of air pollution exposure on acute case-fatality of stroke and acute myocardial infarction (AMI) in a setting where pollutant levels are rather low.. We leveraged the data from the Takashima Stroke and AMI Registry, which covers a population of approximately 55,000 in Takashima County located in central Japan. The study period of 6,210 days (16 years, leap years also taken into account) were divided into quartiles of daily average pollutant concentration; suspended particulate matter (SPM), sulfur dioxide (SO(2)), nitrogen dioxide (NO(2)), and photochemical oxidants (Ox). The stroke and AMI events were categorized to corresponding quartiles based on the pollution levels of the onset day. To study the effects of air pollutants, we estimated the fatality rate ratio across quartiles of the pollutants where the lowest quartile served as the reference.. There were 307 (men: 153 and women: 154) fatal stroke cases within 28 days of onset among the 2,038 first ever stroke during 1988-2004. In the same period, there were 142 (men: 94 and women: 54) fatal AMI cases within 28 days of onset among the 429 first ever AMI events. The mean of the measured pollutant levels were as follows: SPM 26.9 µg/m(3), SO(2) 3.9 ppb, NO(2) 16.0 ppb, and Ox 28.4 ppb. Among the pollutants, higher levels of NO(2) showed increased fatality risk. In multi-pollutant model, the highest quartile of NO(2) was associated with 60% higher stroke case-fatality risk in comparison to lowest quartile of NO(2). In the fully adjusted model the fatality-rate ratio was 1.65 (95% CI 1.06-2.57). This association was more prominent among stroke subtype of cerebral infarction. Other pollutant levels did not show any association with stroke or AMI case-fatality.. We observed association between NO(2) levels, an index of traffic related air pollution, with the acute case-fatality of stroke, especially cerebral infarction in our study population. Further studies are needed in different regions to determine the association between ambient air pollutants and acute cardiovascular fatalities.

Topics: Acute Disease; Adult; Aged; Air Pollutants; Air Pollution; Cerebral Hemorrhage; Cerebral Infarction; Female; Humans; Japan; Male; Middle Aged; Models, Biological; Myocardial Infarction; Nitrogen Dioxide; Oxidants, Photochemical; Particulate Matter; Registries; Stroke; Subarachnoid Hemorrhage; Sulfur Dioxide; Vehicle Emissions

Evidence linking short-term exposure to outdoor air pollution with hemorrhagic stroke is inconsistent.. We evaluated the associations between outdoor air pollution and specific types of stroke in Tokyo, Japan, from April 2003 to December 2008. We obtained daily counts of stroke mortality (n = 41,440) and concentrations of nitrogen dioxide as well as particles less than 2.5 μm in diameter. Time-series analysis was employed.. Although same-day air pollutants were positively associated with ischemic stroke and intracerebral hemorrhage mortality, both air pollutants were more strongly associated with subarachnoid hemorrhage mortality: rate ratio was 1.041 (95% confidence interval: 1.011-1.072) for each 10 μg/m3 increase in the previous-day particles less than 2.5 μm.. This study suggests that short-term exposure to outdoor air pollution increases the risks of hemorrhagic stroke mortality as well as ischemic stroke mortality.

Topics: Air Pollutants; Air Pollution; Cerebral Hemorrhage; Environmental Exposure; Humans; Nitrogen Dioxide; Particulate Matter; Risk Factors; Stroke; Subarachnoid Hemorrhage; Tokyo