1271Short-term effects of exposure to ambient fine particulate matter on out-of-hospital cardiac arrest: a nationwide case-crossover study in Japan

Introduction

The cardiovascular health consequences of ambient air pollution generally equal or exceed those due to pulmonary diseases and cancers. Particulate matter less than 2.5μm in aerodynamic diameter (PM2.5) has become a major focus of research on the short-term exposure to air pollution and cardiovascular disease. However, the evidence regarding the association between several air pollutants and out-of-hospital cardiac arrest (OHCA), has been inconsistent, which could be due to limited sample sizes (∼11,000). Thus, a larger study may assist in characterising possible associations.

Purpose

This study aimed to identify the associations between exposure to ambient air pollution and the incidence of OHCA in Japan.

Methods

A case-crossover design was used to determine the odds ratio (OR) of OHCA across Japan with daily exposure of PM2.5, carbon monoxide (CO), photochemical oxidants (Ox), and sulfur dioxide (SO2) on the day of the arrest or 1–3 days before it (lag 0–3). OHCA cases were identified through the All-Japan Utstein registry of the Fire and Disaster Management Agency from January 1, 2014 to December 31, 2015. All cause OHCAs were investigated by conditional logistic regression adjusted for daily temperature and relative humidity.

Results

A total of 249,372 OHCAs were included during study period. Each 10 μg/m3 increase in daily PM2.5 exposure over 4 days was associated with all cause OHCA risk (lag 0: OR 1.017, 95% confidence interval (CI) 1.010, 1.024; lag 1: OR 1.015, 95% CI 1.008, 1.022; lag 2: OR 1.018, 95% CI 1.011, 1.025; lag 3: OR 1.021, 95% CI 1.014, 1.028; lag 0–1: OR 1.022, 95% CI 1.014, 1.030). CO, Ox and SO2 also showed significant associations with OHCAs. In the multi-pollutant model, the effects of PM2.5 remained independent of CO, Ox and SO2 (Table).

Conclusion

Short-term exposure to PM2.5 was independently associated with an increased risk of OHCA.

2284Sex and age differences in short-term exposure to ambient fine particulate matter and out-of-hospital cardiac arrest: a nationwide case-crossover study in Japan

Introduction

Accumulating evidence has shown the elevated risk for cardiovascular diseases (CVD) with exposure to air pollution, such as fine particles <2.5μm in aerodynamic diameter (PM2.5). A bi-directional relationship exists between air pollution and traditional CV risk factors like obesity, diabetes, and hypertension. However, little is known about the effect of age and sex on association between ambient air pollution and out-of-hospital cardiac arrest (OHCA).

Purpose

This study aimed to identify sex and age differences in the associations between exposure to PM2.5 and OHCA in Japan.

Methods

A case-crossover design was used to determine the odds ratio (OR) of OHCA across Japan with daily PM2.5 exposure on the day of the arrest or 1–3 days before it (lag 0–3). OHCA cases were identified through the All-Japan Utstein registry of the Fire and Disaster Management Agency from January 1, 2014 to December 31, 2015. OHCAs were investigated by conditional logistic regression adjusted for daily temperature and relative humidity with stratification by sex and age.

Results

A total of 249,372 OHCAs were included during study period. Their mean age was 75 years and 57% were male. Each 10 μg/m3 increase in daily PM2.5 exposure over 4 days was associated with all cause OHCA risk for male (lag 0: OR 1.022, 95% confidence interval (CI) 1.013, 1.031; lag 1: OR 1.016, 95% CI 1.007, 1.025; lag 2: OR 1.016, 95% CI 1.007, 1.026; lag 3: OR 1.017, 95% CI 1.008, 1.027; lag 0–1: OR 1.025, 95% CI 1.015, 1.036). Increased risk in OHCA was also found with lag 1 to lag 3 PM2.5 exposure among women. Lag 0 to lag 3 PM2.5 exposures were significantly associated with OHCA among patients older than 65 years. Among 35 to 64 years, only lag 3 PM2.5 exposure was associated with an increased risk in OHCA. No significant association was observed between PM2.5 exposure and OHCA among patients less than 35 years.

Conclusions

Short-term exposure to PM2.5 is associated with an increased risk of OHCA in both sexes. Patients older than 65 years were more susceptible to PM2.5 exposure than younger age group.

Extended Sessions of Polymyxin-B Immobilized Fiber Column Hemoperfusion Ameliorate Renal Outcome and Mortality in Septic Shock with Acute Kidney Injury

Background/Aims: Polymyxin-B (PMX) treatment has been reported to decrease mortality in patients with septic shock and acute kidney injury (AKI). In this study, we aimed to evaluate whether extended sessions of PMX (Ext-PMX) immobilized fiber column hemoperfusion ameliorate clinical outcomes in patients complicated with septic shock and AKI without surgical control. Methods: Twenty-two patients with nonsurgical septic shock and AKI who received PMX were included. They were divided according to the duration of PMX treatment: Ext-PMX and standard PMX (Std-PMX). Results: The mean blood pressure increased and inotrope requirement decreased within 24 h after PMX initiation. The median value of predicted mortality was 52.5%, and the ­28-day mortalities in the Ext-PMX and Std-PMX groups were 44.4 and 75% respectively. Renal replacement therapy (RRT) was also initiated in 17 patients, and renal insufficiency was recovered. Conclusion: Ext-PMX combined with RRT improved clinical outcomes in patients with nonsurgical septic shock and AKI.