Long-term exposure to particulate air pollution and presence and progression of carotid artery plaques - A northern Sweden VIPVIZA cohort study

The influence of PM2.5 exposure duration and concentration on outpatient visits of urban hospital in a typical heavy industrial city

To explain the duration and dose effects of pollutant exposure on public health and provide scientific data for air pollution prevention and control and disease prevention by examining the influence of PM2.5 concentration and exposure duration on daily outpatient visits among patients with cardiovascular, cerebrovascular, and respiratory diseases in a typical heavy industrial city in China. Daily outpatient data on cardiovascular, cerebrovascular, and respiratory diseases and regional PM2.5 exposure duration and concentration were collected from a provincial hospital in Taiyuan, China, from 2016 to 2021. The correlations of numeric variables were analyzed using the Pearson correlation method. A generalized additive model (GAMs) was also established to investigate the effects of PM2.5 concentration and exposure duration on outpatient visits. Correlation analysis showed that the outpatient visits in Taiyuan was significantly correlated with the PM2.5 concentration and exposure duration. The longer the exposure time of PM2.5 pollution, the stronger the correlation of PM2.5 with outpatient visits showed. Cardiovascular outpatient visits were extremely significant related with medium to long-term exposure of PM2.5 (exposure with more than 30 days) (p < 0.001). In addition, outpatient visits of cerebrovascular and respiratory disease were extremely significant correlated with PM2.5 (exposures within 0-360 days) (p < 0.001). The results of GAMs showed the linear or the nonlinear relationships between outpatient visits and exposure of PM2.5. Among the linear relationships, when average concentration of PM2.5 (exposure within less than 15 days) increased by 1 mg/m3, the cardiovascular outpatient visits increased most dramatically (by about 440 people). For nonlinear relationships, when the average PM2.5 concentration (exposure with over 30 days or more) increased by 1 mg/m3, the most dramatic increase occurred in cardiovascular outpatient visits (with a maximum increase of 7000), followed by cerebrovascular outpatient visits (with a maximum increase of 1200), and respiratory outpatient visits (with a maximum increase of 250). The GAMs also revealed a dose effect in the relationship between outpatient visits and PM2.5 exposure. In moderately polluted air (based on air quality standards of China, GB3095-2012), when the average concentration of PM2.5 increased by 1 mg/m3, the cardiovascular outpatient visits increased the most (by 1200 people), followed by cerebrovascular outpatient visits (by 200 people) and respiratory outpatient visits (by 20 people). We concluded that outpatient visits in cardiovascular, cerebrovascular, and respiratory disease are closely correlated with the concentration and exposure duration of air pollution. There is a linear relationship between short-term air pollution exposure (exposure within less than 15 days) and outpatient visits. As PM2.5 concentration increases, cardiovascular outpatient visits increase gradually, with its growth trend exceeding that of cerebrovascular and respiratory disease. There is a nonlinear relationship between medium and long-term air pollution exposure (exposure with more than 30 days) and outpatient visits, with cardiovascular and cerebrovascular outpatient visits showed a nonlinear but overall upward trend when the atmosphere is moderately polluted.

Associations of time-weighted individual exposure to ambient particulate matter with carotid atherosclerosis in Beijing, China

BACKGROUND

Time-location information (time spent on commuting, indoors and outdoors around residential and work places and physical activity) and infiltrated outdoor pollution was less considered estimating individual exposure to ambient air pollution. Studies investigating the association between individual exposure to particulate matter (PM) with aerodynamic diameter < 10 μm (PM₁₀) and < 2.5 μm (PM_2.5) and carotid atherosclerosis presented inconsistent results. Moreover, combined effect of pollutants on carotid atherosclerosis was not fully explored. We aimed to investigate the association between long-term individual time-weighted average exposure to PM_2.5 and PM₁₀ and the risk of carotid atherosclerosis, and further explore the overall effect of co-exposure to pollutants on carotid atherosclerosis.

METHODS

The study population included 3069 participants derived from the Beijing Health Management Cohort (BHMC) study. Daily concentration of ambient air pollutants was estimated by land-use regression model at both residential and work addresses, and one- and two-year time-weighted average individual exposure was calculated by further considering personal activity pattern and infiltration of ambient air pollution indoors. We explored the association of PM_2.5 and PM₁₀ with carotid atherosclerosis and pooled the overall effect of co-exposure to ambient air pollutants by quantile g-computation.

RESULTS

A significant association between time-weighted average exposure to PM_2.5 and PM₁₀ and carotid atherosclerosis was observed. Per interquartile range increase in two-year exposure to PM_2.5 (Hazard ratio (HR): 1.322, 95% confidence interval (CI): 1.219-1.434) and PM₁₀ (HR:1.213, 95% CI: 1.116-1.319) showed the strongest association with carotid atherosclerosis, respectively. Individuals in higher quartiles of pollutants were at higher risk for carotid atherosclerosis compared with those in the lowest quartile group. Concentration response functions documented the nearly linear and nonlinear relationship and interpreted the upward trends of the risk for carotid atherosclerosis with increasing level of pollutant concentrations. Moreover, effect estimates for the mixture of pollutants and carotid atherosclerosis were larger than any of the individual pollutants (HR (95% CI) was 1.510 (1.338-1.704) and 1.613 (1.428-1.822) per quartile increase for one-year and two-year time-weighted average exposure, respectively).

CONCLUSIONS

Individual time-weighted average exposure to PM_2.5 and PM₁₀ was associated with carotid atherosclerosis. Co-exposure to ambient air pollution was also positively associated with carotid atherosclerosis.

Long-term effects of PM2.5 components on hypertension: A national analysis in China

BACKGROUND

Evidence is less about the associations between fine particulate matter (PM_2.5) components and hypertension. We aimed to examine the long-term effects of PM_2.5 components on prevalence of hypertension, diastolic blood pressure (DBP) and systolic blood pressure (SBP).

METHODS

We included participants between March 1, and July 31, 2021, from 13 provinces in China. Geocoded residential address was used for exposure assignment. Mixed-effect regression was used to assess 3-year average concentrations of PM_2.5 and its components (black carbon, organic matter, nitrate, ammonium, and sulfate) on prevalence of hypertension, DBP and SBP with covariate-adjusted. SHapley Additive exPlanation was used to compare the contribution of PM_2.5 components to hypertension, DBP, and SBP. Sex and age subgroup were also analyzed.

RESULTS

We enrolled a total of 113,159 participants aged ≥18 years. Long-term exposure to PM_2.5 and its components (black carbon, organic matter, nitrate, ammonium, and sulfate) had associations with prevalence of hypertension, with the Odds Ratios and 95% confidence interval (CI) of 1.06 (95%CI: 1.03-1.09), 1.07 (95%CI: 1.04-1.09), 1.07 (95%CI: 1.04-1.10), 1.05 (95%CI: 1.01-1.08), 1.03 (95%CI: 1.00-1.06), and 1.03 (95%CI: 1.00-1.04), respectively. Effects of that except for black carbon on DBP with per interquartile upticks of concentration were 0.23 (95%CI: 0.11-0.35), 0.17 (95%CI: 0.04-0.29), 0.35 (95%CI: 0.21-0.48), 0.40 (95%CI: 0.28-0.52), and 0.25 (95%CI: 0.13-0.26), respectively. Ammonium was associated with SBP, corresponding to an increase of 0.18 (95%CI: 0.01-0.35). Males had higher risks of DBP (Z = 2.54-6.08, P < 0.001). Older people were substantially more affected by PM_2.5 and its components. Nitrate showed the highest contribution to hypertension, DBP and SBP compared with other components.

CONCLUSIONS

Long-term exposure to PM_2.5 and its components had adverse consequences on prevalence of hypertension, DBP and SBP, especially for males and older people. Nitrate contributed the highest to hypertension, DBP and SBP. Findings may have implications for pollution and hypertension control.

PM2.5 induces the abnormal lipid metabolism and leads to atherosclerosis via Notch signaling pathway in rats

PM_2.5 can affect the lipid metabolism and cause atherosclerosis. Abnormal lipid metabolism is a sever risk factor of atherosclerosis and the underlying molecular mechanism still remains unclear. In this study, GPL16956 Agilent-045997 Arraystar human lncRNA microarray V3 (Probe Name Version) platform was used to detect the different genes of lipid metabolism between the normal arterial intima and advanced atherosclerotic plaque, which were downloaded from GEO database. A high-fat diet and vitamin D3 were administered to Wistar rats to establish the atherosclerotic model and another normal healthy 56 rats were used as the non-atherosclerotic exposure groups. The atherosclerotic rats and non-atherosclerotic rats were randomly divided into 4 PM_2.5 groups (0, 1.5, 7.5, 37.5 mg/kg), respectively. The results of bioinformatics showed changes in the Notch1, Dll1, Hes1, LDLR and ABCG1 levels. PM_2.5 exposure could produce damage to the physiological structure of the aorta, and aggravate atherosclerosis in rats from both non-atherosclerotic and atherosclerotic groups. With the increase of the exposure dose, the levels of TC and TG significantly increased. PM_2.5 exposure significantly affected the expression levels of PPARγ, ABCA1, LDLR, CD36, SR-BI and SREBP2. PM_2.5 exposure could also affect the expression levels of the Notch signaling pathways which was significantly correlated with the levels of TC and TG. The results proved that PM_2.5 exposure could induce and aggravate the atherosclerosis in rats by disrupting lipid metabolism in which Notch signaling pathway may play a significant role.