The joint effect of long-term exposure to multiple air pollutants on non-accidental and cause-specific mortality: A longitudinal cohort study

Ambient fine particulate matter and mortality risk among people with disability in Korea based on the National Health Insurance database: a retrospective cohort study

BACKGROUND

People with disabilities (PWD) may be more vulnerable to the adverse health effects of air pollution than the general population. This study examined the association between long-term exposure to ambient fine particulate matter (PM2.5) and mortality risk in PWD considering disability type and severity.

METHODS

Data from the Korean National Health Insurance Service and Statistics Korea were analyzed in this retrospective cohort study, including 2,880,265 individuals (41,501,709 person-years), of which 176,410 were PWD (2,011,231 person-years). PM2.5 exposure was estimated using simulated data from 2006 to 2019. Causes of death included all causes, non-accidental causes, respiratory disease, lung cancer, and cardiovascular disease. Cox proportional hazard models were used to estimate hazard ratios (HRs) for mortality associated with PM2.5 stratified by disability type and severity.

RESULTS

PWD, particularly those with severe disabilities or specific impairments such as kidney problems or brain lesions, showed significantly high mortality risks from all causes, non-accidental causes, and cardiovascular diseases due to PM2.5 exposure. For individuals with kidney impairment, the HR (95% confidence interval) for mortality on increasing PM2.5 by 10 µg/m3 was 1.79 (1.27-2.52) from all causes, while for those with brain lesions, it was 1.10 (1.00-1.22) from cardiovascular disease. PWD were not susceptible to mortality from respiratory causes.

CONCLUSIONS

This study highlights the increased vulnerability of PWD, especially those with severe disabilities or specific impairments, to the adverse effects of PM2.5 exposure. Targeted interventions tailored to disability type and severity, along with stricter air quality standards and specialized healthcare approaches, are needed.

Long-term exposure to ambient air pollutants and risk of prostate cancer: A prospective cohort study

BACKGROUND

Air pollution has been hypothesized as a potential risk factor for prostate cancer, while previous studies on the topic mainly focused on single pollutant and the results were inconsistent. This study aimed to investigate the association between long-term exposure to multiple air pollutants and the risk of prostate cancer and their joint effect.

METHODS

This study included 210,722 men free of prostate cancer at baseline from the UK Biobank. Data on ambient air pollutants, including particulate matter with diameters ≤2.5 μm (PM2.5), ≤10 μm (PM10), nitrogen oxides (NO2 and NOx), sulfur dioxide (SO2), benzene, and ozone (O3) were collected from the UKs Department for Environment, Food and Rural Affair during 2003-2021.

RESULTS

During a median follow-up of 10.9 years, a total of 10,841 incident prostate cancer occurred. The hazard ratios (95% confidence intervals) of prostate cancer for each interquartile range increase in PM2.5, PM10, NO2, NOx, SO2, benzene and O3 were 1.120 (1.084-1.158), 1.121 (1.089-1.155), 1.040 (1.009-1.071), 1.040 (1.012-1.069), 0.983 (0.958-1.009), 1.080 (1.050-1.111), and 1.080 (1.050-1.111), respectively. The joint effect of PM2.5, PM10, NO2, NOx, SO2, and benzene was 1.039 (1.012-1.067). with the greatest contribution from NOx, PM10, benzene, and PM2.5. The impact of PM2.5, PM10, NO2, NOx and benzene on prostate cancer risk was weakened by a higher percentage of greenness at the home location buffer.

CONCLUSIONS

Long-term exposure to air pollutants may be positively associated with an elevated risk of prostate cancer, particularly for NOx, PM10, benzene, and PM2.5. This study highlights the potential role of comprehensively assessing and controlling various air pollutants in prevention of prostate cancer.

Influence of air pollution on the nonaccidental death before and after the outbreak of COVID-19

BACKGROUND

During the COVID-19 pandemic, non-therapeutic interventions (NPIs), such as traffic restrictions, work stoppages, and school suspensions, have led to a sharp decline in the concentration of air pollutants in the epidemic sites. However, few studies focused on the impact of air pollutant changes on the risk of nonaccidental death.

METHOD

We selected Yancheng City, China, as the study site and applied a Generalized Additive Model (GAM) based on the quasi-Poisson distribution to evaluate the impact of atmospheric pollutants exposure on the nonaccidental death of local residents. The time span of this study was set from January 1, 2013, to December 21, 2022, that is, before and after the outbreak of COVID-19.

RESULTS

The concentration of some air pollutants has greatly varied after the outbreak of COVID-19, with a significant decline for PM2.5 (- 43.4%), PM10 (- 38.5%), SO2 (- 62.9%), and NO2 (- 22.6%), but an increase for O3 (+ 4.3%). Comparative analysis showed that PM2.5 contributed to an increased risk of nonaccidental death after the outbreak of COVID-19. With an increase in PM2.5 by 10 µg/m³, the excess relative risks (ER) of nonaccidental death of residents increased by 1.01% (95%CI: 0.19%,1.84%). The stratified analysis revealed that air pollutants impacted nonaccidental deaths in both men and women before the outbreak of COVID-19. After the outbreak of COVID-19, PM10 had a significant effect on male nonaccidental deaths. The concentrations of PM2.5, PM10, and SO2 increased by 10 µg/m³, the ER of PM2.5, PM10, and SO2 on female nonaccidental death increased by 1.52% (0.38%,2.67%), 0.58% (0.02%,1.13%), and 15.09% (5.73%,25.28%), respectively. Before the outbreak of COVID-19, five air pollutants had an impact on the death of residents from cardiovascular disease (CVD). After the outbreak of COVID-19, only PM10 significantly affected the death risk of CVD. In addition, we discovered that PM2.5, PM10, and SO2 significantly impacted the risk of death due to respiratory diseases before and after the outbreak of COVID-19.

CONCLUSIONS

Air pollutants have different effects on nonaccidental deaths before and after the COVID-19 outbreak. A decrease in air pollutant concentration due to the NPIs for COVID-19 had a significant effect on the reduction of the risk of nonaccidental death.

Association of Smoking with Chronic Kidney Disease Stages 3 to 5: A Mendelian Randomization Study

Background: Previous studies suggested that smoking behavior (e.g., smoking status) was associated with an elevated risk of chronic kidney disease (CKD), yet whether this association is causal remains uncertain. Methods: We used data for half million participants aged 40 to 69 years from the UK Biobank cohort. In the traditional observational study, we used Cox proportional hazards models to calculate the associations between 2 smoking indices-smoking status and lifetime smoking index and incident CKD stages 3 to 5. Mendelian randomization (MR) approaches were used to estimate a potential causal effect. In one-sample MR, genetic variants associated with lifetime smoking index were used as instrument variables to examine the causal associations with CKD stages 3 to 5, among 344,255 UK Biobank participants with white British ancestry. We further validated our findings by a two-sample MR analysis using information from the Chronic Kidney Disease Genetics Consortium genome-wide association study. Results: In the traditional observational study, both smoking status [hazard ratio (HR): 1.26, 95% confidence interval (CI): 1.22 to 1.30] and lifetime smoking index (HR: 1.22, 95% CI: 1.20 to 1.24) were positively associated with a higher risk of incident CKD. However, both our one-sample and two-sample MR analyses showed no causal association between lifetime smoking index and CKD (all P > 0.05). The genetic instruments were validated by several statistical tests, and all sensitivity analyses showed similar results with the main model. Conclusion: Evidence from our analyses does not suggest a causal effect of smoking behavior on CKD risk. The positive association presented in the traditional observational study is possibly a result of confounding.