Acute effect of fine and coarse particular matter on cardiovascular visits in Ningbo, China.

Although a growing number of epidemiological studies have been conducted on size-specific health effects of particulate matter in China, results remain inconsistent. In this study, we investigated acute effect of fine and coarse particular matter on cardiovascular hospital visits in Ningbo, China. We used generalized additive models to examine short-term effects of PM2.5 and PM10-2.5 on cardiovascular hospital visits by adjustment for temporal, seasonal, and meteorological effects. Subgroup analyses were conducted by age, sex, and season. We also examined the stability of their effects in multi-pollutant models. We found that PM2.5 were associated with cardiovascular hospital visits (RR = 1.006; 95% CI 1.000, 1.011) and results remained similar after adjustment for PM10-2.5 (RR = 1.005; 95% CI 0.998, 1.013). There was a borderline association between PM10-2.5 and cardiovascular hospital visits (RR = 1.007; 95% CI 0.997, 1.016), which disappeared after controlling for PM2.5 (RR = 1.000; 95% CI 0.988, 1.013). The associations appeared to be stronger in the cold season and among the elderly (≥ 75 years). The findings of this study suggested significant adverse effects of PM2.5, but no independent effects of PM10-2.5 on cardiovascular hospital visits. Additional studies are needed to confirm these findings.

Baseline and longitudinal change in blood pressure and mortality in a Chinese cohort.

BACKGROUND: A J-curve association has been demonstrated for blood pressure (BP) and all-cause mortality, but data on longitudinal change of BP and mortality in Chinese population are limited. METHODS: We performed a retrospective cohort study to examine the association between BP (at baseline and longitudinal change) and risk of mortality in Yinzhou District, Ningbo, China, based on the Yinzhou Health Information System. At baseline, a total of 181 352 subjects aged over 18 years with at least one BP examination record were recruited through the Yinzhou Health Information System. The final analysis was restricted to 168 061 participants after exclusion of outliers of BP. RESULTS: A U-shaped association was observed for BP at baseline and risk of total and cardiovascular mortality. When compared with normotensive participants, patients with hypotension (HRs=1.51, 95% CI 1.21 to 1.88) and stage 3 hypertension (1.28, 95% CI 1.09 to 1.50) had an increased risk of all-cause mortality. Relative to stable BP of normotension, having a rise in BP from normotension to hypertension or from prehypertension to hypertension both conferred an increased risk of total and cardiovascular mortality (total: 1.39 (95% 1.10 to 1.75) and 1.40 (95% 1.15 to 1.69); cardiovascular: 2.22 (95% CI 1.35 to 3.65) and 1.89 (95% CI 1.20 to 2.96), respectively). CONCLUSIONS: Our findings emphasise that hypotension and stage 3 hypertension were associated with an increased risk of all-cause mortality. Longitudinal change from normotensive or prehypertensive levels to 140/90 mm Hg or higher could increase the risk of total and cardiovascular mortality.

Association between short-term exposure to ambient air pollution and daily mortality: a time-series study in Eastern China.

Few studies were conducted to evaluate health effects of acute exposure to PM2.5 and daily mortality in Asian countries due to lack of large-scale PM2.5 monitoring data. We conducted a time-series study to examine the associations of short-term exposure to four common air pollutants (PM2.5, PM10, NO2, and SO2) and daily mortality in Ningbo, Zhejiang, China. We used generalized addictive model (GAM) to estimate relative risks (RRs) and 95% confidence intervals (CIs) for the association of these four air pollutants with daily mortality. The study included 9365 people in the 2-year study period from 2014 to 2015. SO2 were significantly associated with risk of NAD, RD, and CD mortality with RRs of 1.034 (95% CI 1.004, 1.064), 1.067 (95% CI 1.010, 1.127), and 1.049 (95% CI 1.001, 1.098), respectively.PM2.5 and PM10 were significantly associated with risk of death from NAD mortality in warm season. Similar associations were observed for PM10 (RR = 1.056, 95% CI 1.004, 1.111) and risk of CD mortality. The study provides further evidence that short-term exposure to PM2.5, PM10, NO2, and SO2 are associated with increased risk of daily mortality.

Effects of air pollution on hospital visits for pneumonia in children: a two-year analysis from China.

Although the effect of air pollution on respiratory health has been identified, few studies can be available to evaluate the association of air pollution with hospital visits for children's pneumonia in China. To explore whether high concentrations of air pollutants (including PM2.5, PM10, NO2, and SO2) are related to hospital visits for pneumonia in children, we conducted a population-based time-series study in Ningbo, China, from January 1st, 2014 to November 1st, 2015. We used a generalized additive Poisson regression model to calculate risk ratios and 95% confidence intervals for the associations of air pollutants and hospital visits for pneumonia in children and found that these four pollutants were associated with the increased hospital visits for pneumonia in children (1.3% for PM2.5, 1.0% for PM10, 2.9% for NO2, 5.0% for SO2 per 10-µg/m3 increase in PM2.5, PM10, NO2, and SO2, respectively). Stronger associations were observed in the cold seasons and among children under 5 years.

Air pollution and hospital visits for acute upper and lower respiratory infections among children in Ningbo, China: A time-series analysis.

Acute upper and lower respiratory infections are main causes of mortality and morbidity in children. Air pollution has been recognized as an important contributor to development and exacerbation of respiratory infections. However, few studies are available in China. In this study, we investigated the short-term effect of air pollution on hospital visits for acute upper and lower respiratory infections among children under 15 years in Ningbo, China. Poisson generalized models were used to estimate the associations between air pollution and hospital visits for acute upper and lower respiratory infections adjusted for temporal, seasonal, and meteorological effects. We found that four pollutants (PM2.5, PM10, NO2, and SO2) were significantly associated with hospital visits for acute upper and lower respiratory infections. The effect estimates for acute upper respiratory infections tended to be higher (PM2.5 ER = 3.46, 95% CI 2.18, 4.76; PM10 ER = 2.81, 95% CI 1.93, 3.69; NO2 ER = 11.27, 95% CI 8.70, 13.89; SO2 ER = 15.17, 95% CI 11.29, 19.19). Significant associations for gaseous pollutants (NO2 and SO2) were observed after adjustment for particular matter. Stronger associations were observed among older children and in the cold period. Our study suggested that short-term exposure to outdoor air pollution was associated with hospital visits for acute upper and lower respiratory infections in Ningbo.