Modification of the association between ambient air pollution and lung function by frailty status among older adults in the Cardiovascular Health Study

Haze weather and mortality in China from 2014 to 2020: Definitions, vulnerability, and effect modification by haze characteristics

Haze weather, characterized by low visibility due to severe air pollution, has aroused great public concern. However, haze definitions are inconclusive, and multicentre studies on the health impacts of haze are scarce. We collected data on the daily number of deaths and environmental factors in 190 Chinese cities from 2014 to 2020. The city-specific association was estimated using quasi-Poisson regression and then pooled using meta-analysis. We found a negative association between daily visibility and non-accidental deaths, and mortality risk sharply increased when visibility was < 10 km. Haze weather, defined as a daily average visibility of < 10 km without a limit for humidity, produced the best model fitness and greatest effect on mortality. A haze day was associated with an increase of 2.53% (95% confidence interval [CI]:1.96, 3.10), 2.84 (95% CI: 2.13, 3.56), and 2.99% (95% CI: 1.94, 4.04) in all non-accident, cardiovascular and respiratory mortality, respectively. Haze had the greatest effect on lung cancer mortality. The haze-associated risk of mortality increased with age. Severe haze (visibility <2 km) and damp haze (haze with relative humidity >90%) had greater health impacts. Our findings can help in the development of early warning systems and effective public health interventions for haze.

Differential effects of size-specific particulate matter on frailty transitions among middle-aged and older adults in China: findings from the China Health and Retirement Longitudinal Study (CHARLS), 2015-2018

BACKGROUND

This study aimed to assess the long-term effects of size-specific particulate matter (PM) on frailty transitions in middle-aged and older Chinese adults.

METHODS

We included 13 910 participants ≥45 y of age from the China Health and Retirement Longitudinal Study (CHARLS) for 2015 and 2018 who were classified into three categories in 2015 according to their frailty states: robust, prefrail and frail. Air quality data were obtained from the National Urban Air Quality Real-time Publishing Platform. A two-level logistic regression model was used to examine the association between concentrations of PM and frailty transitions.

RESULTS

At baseline, the total number of robust, prefrail and frail participants were 7516 (54.0%), 4324 (31.1%) and 2070 (14.9%), respectively. Significant associations were found between PM concentrations and frailty transitions. For each 10 μg/m3 increase in the 3-y averaged 2.5-μm PM (PM2.5) concentrations, the risk of worsening in frailty increased in robust (odds ratio [OR] 1.06 [95% confidence interval {CI} 1.01 to 1.12]) and prefrail (OR 1.07 [95% CI 1.01 to 1.13]) participants, while the probability of improvement in frailty in prefrail (OR 0.91 [95% CI 0.84 to 0.98]) participants decreased. In addition, the associations of PM10 and coarse fraction of PM with frailty transitions showed similar patterns.

CONCLUSIONS

Long-term exposure to PM was associated with higher risks of worsening and lower risks of improvement in frailty among middle-aged and older adults in China.

Causal association between air pollution and frailty: a Mendelian randomization study

Backgrounds

Frailty is a significant problem for older persons since it is linked to a number of unfavorable consequences. According to observational researches, air pollution may raise the risk of frailty. We investigated the causal association between frailty and air pollution (including PM2.5, PM2.5-10, PM10, nitrogen dioxide, and nitrogen oxides) using Mendelian randomization approach.

Methods

We conducted MR analysis using extensive publically accessible GWAS (genome-wide association studies) summary data. The inverse variance weighted (IVW) method was employed as the primary analysis method. The weighted median model, MR-Egger, simple model, and weighted model approaches were chosen for quality control. The Cochran's Q test was utilized to evaluate heterogeneity. Pleiotropy is found using the MR-Egger regression test. The MR-PRESSO method was used to recognize outliers. The leave-one-out strategy was used to conduct the sensitivity analysis.

Results

MR results suggested that PM2.5 was statistically significantly associated with frailty [odds ratio (OR) = 1.33; 95%confidence interval (CI) = 1.12-1.58, p = 0.001] in IVW method. We observed no statistical association between PM2.5-10(OR = 1.00, 95% CI = 0.79-1.28, p = 0.979), PM10(OR = 0.91, 95% CI = 0.75-1.11, p = 0.364), nitrogen dioxide (OR = 0.98, 95% CI = 0.85-1.12, p = 0.730), nitrogen oxides (OR = 1.15, 95% CI = 0.98-1.36, p = 0.086) and frailty. There was no pleiotropy in the results. The sensitivity analysis based on the leave-one-out method showed that the individual single nucleotide polymorphisms (SNPs) did not affect the robustness of the results.

Conclusion

The current MR investigation shows a causal association between PM2.5 and frailty. Frailty's detrimental progression may be slowed down with the help of air pollution prevention and control.

Effect of PM2.5 air pollution on the global burden of lower respiratory infections, 1990-2019: A systematic analysis from the Global Burden of Disease Study 2019

Particulate matter (PM) air pollution is closely related to lower respiratory infections (LRIs). However, the global LRI burden attributable to PM remains unclear. Here, we provide a comprehensive assessment of the PM2.5-attributable LRI burden using data from the Global Burden and Disease Study (GBD) 2019. We found that PM2.5 air pollution contributed to approximately 0.7 million deaths and 37.6 million disability-adjusted life years (DALYs) of LRIs in 2019. The LRI burden attributable to PM2.5 has decreased from 1990 to 2019, with a more pronounced decrease in household PM2.5 than in ambient PM2.5. Unlike the decreasing trend in LRI burden due to household PM2.5 worldwide, nearly one fifth of countries experienced an increase of LRI burden due to ambient PM2.5. The burden was unevenly distributed to less developed countries, mainly in Sub-Saharan Africa. All age groups experienced a decrease in the PM2.5-attributable burden, with the most significant decrease in children younger than 10 years. Notably, individuals aged 20-84 years experienced an increase in the LRI burden attributable to ambient PM2.5. Males had higher burden than females in the elder age and higher SDI regions. This study provided an evidence-based guidance for the prevention of LRIs and control of PM2.5 air pollution.

Impact of lifetime air pollution exposure patterns on the risk of chronic disease

Long-term exposure to air pollution can lead to cardiovascular disease, metabolic syndrome, and chronic respiratory disease. However, from a lifetime perspective, the critical period of air pollution exposure in terms of health risk is unknown. This study aimed to evaluate the impact of air pollution exposure at different life stages. The study participants were recruited from community centers in Northern Taiwan between October 2018 and April 2021. Their annual averages for fine particulate matter (PM2.5) exposure were derived from a national visibility database. Lifetime PM2.5 exposures were determined using residential address information and were separated into three stages (<20, 20-40, and >40 years). We employed exponentially weighted moving averages, applying different weights to the aforementioned life stages to simulate various weighting distribution patterns. Regression models were implemented to examine associations between weighting distributions and disease risk. We applied a random forest model to compare the relative importance of the three exposure life stages. We also compared model performance by evaluating the accuracy and F1 scores (the harmonic mean of precision and recall) of late-stage (>40 years) and lifetime exposure models. Models with 89% weighting on late-stage exposure showed significant associations between PM_2.5 exposure and metabolic syndrome, hypertension, diabetes, and cardiovascular disease, but not gout or osteoarthritis. Lifetime exposure models showed higher precision, accuracy, and F1 scores for metabolic syndrome, hypertension, diabetes, and cardiovascular disease, whereas late-stage models showed lower performance metrics for these outcomes. We conclude that exposure to high-level PM_2.5 after 40 years of age may increase the risk of metabolic syndrome, hypertension, diabetes, and cardiovascular disease. However, models considering lifetime exposure showed higher precision, accuracy, and F1 scores and lower equal error rates than models incorporating only late-stage exposures. Future studies regarding long-term air pollution modelling are required considering lifelong exposure pattern. .¹.

Frailty Risk in Older Adults Associated With Long-Term Exposure to Ambient PM2.5 in 6 Middle-Income Countries

BACKGROUND

A series of studies have explored the health effects of long-term exposure to ambient PM2.5 among older adults. However, few studies have investigated the adverse effect of long-term exposure to ambient PM2.5 on frailty, and the results are inconclusive. This study sought to investigate the associations between long-term exposure to ambient PM2.5 and frailty in 6 low- and middle-income countries.

METHODS

We included an analytical sample of 34 138 individuals aged 50 and older from the Study on global AGEing and adult health Wave 1 (2007/2010). Air pollution estimates were generated using a standard methodology derived from Moderate Resolution Imaging Spectroradiometer observations and Multiangle Imaging Spectroradiometer instruments from the Terra satellite, along with simulations from the GEOS-Chem chemical transport model. A 3-level hierarchical logistic model was used to evaluate the association between frailty index and long-term PM2.5 exposure at 3 levels (individual, province, and country).

RESULTS

In rural areas, each 10 μg/m3 increase in ambient PM2.5 was associated with a 30% increase in the odds of frailty (OR = 1.30, 95% CI: 1.21-1.39) after adjusting for various potential confounding factors. The gender-stratified analysis showed that the association seemed to be slightly stronger in men (OR = 1.31, 95% CI: 1.18-1.46) than in women (OR = 1.21, 95% CI: 1.07-1.36) in rural areas.

CONCLUSION

In a large sample of community-based older adults from 6 middle-income countries, we found evidence that long-term PM2.5 exposure was associated with frailty in rural areas.

Aging Hearts in a Hotter, More Turbulent World: The Impacts of Climate Change on the Cardiovascular Health of Older Adults

PURPOSE OF REVIEW

Climate change has manifested itself in multiple environmental hazards to human health. Older adults and those living with cardiovascular diseases are particularly susceptible to poor outcomes due to unique social, economic, and physiologic vulnerabilities. This review aims to summarize those vulnerabilities and the resultant impacts of climate-mediated disasters on the heart health of the aging population.

RECENT FINDINGS

Analyses incorporating a wide variety of environmental data sources have identified increases in cardiovascular risk factors, hospitalizations, and mortality from intensified air pollution, wildfires, heat waves, extreme weather events, rising sea levels, and pandemic disease. Older adults, especially those of low socioeconomic status or belonging to ethnic minority groups, bear a disproportionate health burden from these hazards. The worldwide trends responsible for global warming continue to worsen climate change-mediated natural disasters. As such, additional investigation will be necessary to develop personal and policy-level interventions to protect the cardiovascular wellbeing of our aging population.

Long-term Ozone Exposure and Small Airways Dysfunction: The China Pulmonary Health (CPH) Study

RATIONALE

It remains unknown whether long-term ozone exposure can impair lung function.

OBJECTIVES

To investigate the associations between long-term ozone exposure and adult lung function in China.

METHODS

Lung function results and diagnosis of small airways dysfunction (SAD) were collected from a cross-sectional study, China Pulmonary Health Study (N=50,991). We used multivariate linear and logistic regression models to examine the associations of long-term ozone exposure with lung function parameters and SAD, respectively, adjusting for demographic characteristics, individual risk factors, and longitudinal trend. We then performed a stratification analysis by chronic obstructive pulmonary disease (COPD).

MEASUREMENTS AND MAIN RESULTS

We observed each 1-standard deviation (SD, 4.9 ppb) increase in warm-season ozone concentrations was associated with a 14.2 mL/s [95% confidence interval (CI): 8.8, 19.6] decrease in forced expiratory flow at 75th percentile of vital capacity and a 29.5 mL/s (95% CI: 19.6, 39.5) decrease in mean forced expiratory flow between the 25th and 75th percentile of vital capacity. The odds ratio of SAD was 1.09 (95% CI: 1.06, 1.11) for a 1-SD increase in warm-season ozone concentrations. Meanwhile, we observed a significant association with a decreased ratio of expiratory volume in 1 second to forced vital capacity (FEV1/FVC) but not with FEV1 or FVC. The association estimates were greater in the COPD group than in the non-COPD group.

CONCLUSION

We found independent associations of long-term ozone exposure with impaired small airways function and higher SAD risks, while the associations with airflow obstruction were weak. COPD patients appear to be more vulnerable.

Global burden of COPD attributable to ambient PM2.5 in 204 countries and territories, 1990 to 2019: A systematic analysis for the Global Burden of Disease Study 2019

The global spatiotemporal pattern of the COPD burden attributable to ambient PM2.5 is unknown in the context of the continuing increase in exposure to ambient PM2.5. Data on COPD burden attributable to ambient PM2.5 from 1990 to 2019 were retrieved from the Global Burden of Disease Study 2019. Cases and age-standardized rates of COPD mortality (ASMR) and disability-adjusted life years (ASDR) were estimated by age, sex, region, and country. The estimated annual percentage change (EAPC) was calculated to quantify the secular trends of ASMR and ASDR from 1990 to 2019. Globally, the number of COPD deaths and DALYs attributable to ambient PM2.5 both increased by over 90% from 1990 to 2019, but ASMR and ASDR both slightly decreased, with EAPC of -0.58 (95% CI: -0.72, -0.44) and -0.40 (95% CI: -0.51, -0.29), respectively. Most COPD deaths and DALYs attributable to PM2.5 occurred in the middle sociodemographic index (SDI) region, but the fastest growth of ASMR and ASDR occurred in the low SDI region, with EAPCs of 2.41 (95% CI: 2.23, 2.59) and 2.34 (95% CI: 2.16, 2.52), respectively. East Asia and South Asia were the high-risk areas of COPD deaths and DALYs attributable to PM2.5, among which China and India were the countries with the heaviest burden. COPD deaths and DALYs attributable to PM2.5 mainly occurred in individuals 70-89 years old and 60-84 years old, respectively. The age-specific rates of mortality and DALYs had a rapid increase in low and low-middle SDI regions from 1990 to 2019. The ASMR or ASDR had a reverse V-shaped relationship with SDI. In summary, the ambient PM2.5-attributable COPD burden is socioeconomic- and age-dependent, and it mediates the heterogeneity of spatial and temporal distribution. Low- and middle-income countries endure the highest ambient PM2.5-attributable COPD burden due to the high exposure to PM2.5 and poor availability and affordability of medicines and diagnostic tests.

Frailty in patients with interstitial lung disease

PURPOSE OF REVIEW

The incidence of age-related diseases such as interstitial lung disease (ILD) is rising, and the importance of multimorbidity and accumulation of health deficits in patients with chronic lung diseases is increasingly recognized. There are multiple relationships between aging and ILD on a demographic and a biological level. Frailty conceptualizes the decline of a patient's physiological reserves and complements the chronological and biological aspects of aging.

RECENT FINDINGS

Frailty affects more than 50% of patients with ILD, with respiratory impairment, accelerated biological aging, comorbidities, medication adverse effects, and social factors collectively playing important roles. Frailty is an independent risk factor for adverse health outcomes such as hospitalizations and early mortality, including before and after lung transplant. Given the multicomponent determinants of frailty, programs such as pulmonary rehabilitation are promising strategies for managing this complex issue.

SUMMARY

Frailty is a common risk factor for adverse outcomes in patients with ILD. The multiple pathways leading to frailty are not completely understood, and further studies are needed to determine the optimal tools for assessment and to develop strategies to prevent and counteract frailty in the aging ILD population.

Residential proximity to major roadways and cognitive function among Chinese adults 65 years and older

Emerging evidence in North America and Europe suggests that traffic-related air pollution (TRAP) adversely affects cognition. However, little is known about this relationship in people living in low- and middle-income countries (LMICs). It is also unknown whether indoor air pollution can modify the effect of TRAP. We derived data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a prospective cohort study, including 11,187 individuals of 82.0 years old (53.9% female). We ascertained residential proximity to major roadways based on self-reports and assessed cognitive function using the Mini-Mental State Examination (MMSE). We used cooking fuel type and home ventilation as proxies for indoor air pollution. We examined the associations between major road proximity and cognitive impairment using multivariable logistic regressions, controlling for demographic, lifestyle, socioeconomic status, and chronic conditions. We did subgroup analyses and assessed the potential interaction effect. The prevalence of cognitive impairment was 33.4%. The adjusted odds ratios of cognitive impairment were 1.20 (1.05, 1.35), 1.26 (1.09, 1.46), 0.99 (0.84, 1.17), and 1.05 (0.88, 1.25) for individuals living <50 m, 50-100 m, 101-200 m, and 201-300 m compared to those living >300 m from a major roadway. In dichotomized analyses, the risk (OR) associated with living closer to roadways was greater in participants who did not implement any ventilation during cooking (compared to those using natural or mechanical ventilation, 1.86 [1.31-2.65] vs. 1.16 [1.03-1.26], P for interaction = 0.001) and in solid fuel users (compared to clean fuel users, 1.37 [1.13-1.67] vs. 1.13 [1.04-1.21], P for interaction = 0.028). The associations were robust in a set of sensitivity analyses. The results suggested that living closer to major roadways was associated with an increased risk for cognitive impairment in older adults in China, indicating an adverse TRAP effect. Indoor air pollution appeared to enhance the TRAP effect synergistically.

Ambient Air Pollution and Mortality among Older Patients Initiating Maintenance Dialysis

BACKGROUND

Fine particulate matter (particulate matter with diameter <2.5 µm [PM2.5]) is associated with CKD progression and may impact the health of patients living with kidney failure. While older (aged ≥65 years) adults are most vulnerable to the impact of PM2.5, it is unclear whether older patients on dialysis are at elevated risk of mortality when exposed to fine particulate matter.

METHODS

Older adults initiating dialysis (2010-2016) were identified from US Renal Data System (USRDS). PM2.5 concentrations were obtained from NASA's Socioeconomic Data and Application Center (SEDAC) Global Annual PM2.5 Grids. We investigated the association between PM2.5 and all-cause mortality using Cox proportional hazard models with linear splines [knot at the current Environmental Protection Agency (EPA) National Ambient Air Quality Standard for PM2.5 of 12 μg/m3] and robust variance.

RESULTS

For older dialysis patients who resided in areas with high PM2.5, a 10 μg/m3 increase in PM2.5 was associated with 1.16-fold (95% CI: 1.08-1.25) increased risk of mortality; furthermore, those who were female (aHR = 1.26, 95% CI: 1.13-1.42), Black (aHR = 1.31, 95% CI: 1.09-1.59), or had diabetes as a primary cause of kidney failure (aHR = 1.25, 95% CI: 1.13-1.38) were most vulnerable to high PM2.5. While the mortality risk associated with PM2.5 was stronger at higher levels (aHR = 1.19, 95% CI: 1.08-1.32), at lower levels (≤12 μg/m3), PM2.5 was significantly associated with mortality risk (aHR = 1.04, 95% CI: 1.00-1.07) among patients aged ≥75 years (Pslope difference = 0.006).

CONCLUSIONS

Older adults initiating dialysis who resided in ZIP codes with PM2.5 levels >12 μg/m3 are at increased risk of mortality. Those aged >75 were at elevated risk even at levels below the EPA Standard for PM2.5.

Metabolomics identifying biomarkers of PM2.5 exposure for vulnerable population: based on a prospective cohort study

Long-term exposure to particular matter (PM), especially fine PM (< 2.5 μm in the aerodynamic diameter, PM_2.5), is associated with increased risk of cardiovascular disorders. This study aimed to evaluate the association between long-term exposure to PM_2.5/PM₁₀ and the metabolic change in the plasma. Specifically, using metabolomics, we sought to identify the biomarkers for the vulnerable subgroup to PM_2.5 exposure. A total of 78 college student volunteers were recruited into this prospective cohort study. All participants received 8 rounds of physical examinations at twice quarterly. Air purifiers were placed in 40 of 78 participants' dormitories for 14 days. Before and after intervention, physical examinations were performed and the peripheral blood was collected. Plasma metabolomics was determined by ultra-performance liquid chromatography-mass spectrometry. During the follow-up, the average concentrations of PM_2.5 and PM₁₀ were 53 μg/m³ and 93 μg/m³, respectively. Totally, 42 and 120 differential metabolic features were detected for PM₁₀ and PM_2.5 exposure, respectively. In total, 25 differential metabolites were identified for PM_2.5 exposure, most of which were phospholipids. No distinctive metabolites were found for PM₁₀ exposure. A total of 6 differential metabolites (lysoPC (P-20:0), lysoPC (P-18:1(9z)), lysoPC (20:1), lysoPC (O-16:0), choline, and found 1,3-diphenylprop-2-en-1-one) were characterized and confirmed for sensitive individuals. Importantly, we found LysoPC (P-20:0) and LysoPC (P-18:1(9z)) changed significantly before and after air purifier intervention. Our results indicated that the phospholipid catabolism was involved in long-term PM_2.5 exposure. LysoPC (P-20:0) and LysoPC (P-18:1(9z)) may be the biomarkers of PM_2.5 exposure.

Effects of PM10 and Weather on Respiratory and Cardiovascular Diseases in the Ciuc Basin (Romanian Carpathians)

This study presents the PM10 concentration, respiratory and cardiovascular disease hospital admissions evolution in the Ciuc basin for a period of 9 years (2008–2016), taking into consideration different meteorological conditions: boundary layer, lifting condensation level, temperature-humidity index, and wind chill equivalent chart index. The PM10 and hospital admissions evolution showed a very fluctuated hourly, weekly, monthly, yearly tendency. The PM10 concentration in winter (34.72 μg/m3) was 82% higher than the multiannual average (19.00 μg/m3), and almost three times higher than in summer (11.71 μg/m3). During the winter, PM10 concentration increased by an average of 9.36 μg/m3 due to the increased household heating. Climatological parameters have a demonstrable effect on the PM10 concentration variation. Children, the elderly and men are more sensitive to air pollution, the calculated relative risk for men was (RR = 1.45), and for women (RR = 1.37), respectively. A moderate correlation (0.51) was found between PM10 and pneumonia (P), while a relatively weak correlation (0.39) was demonstrated in the case of PM10 and upper respiratory tract infections (URTI). Furthermore, except thermal humidity index (THI), strong negative correlations were observed between the multiannual monthly mean PM10 and the meteorological data. The PM10 followed a moderate negative correlation with the boundary layer (−0.61). In the case of URTI and P, the highest number of hospital admissions occurred with a 5 to 7-day lag, while the 10 μg/m3 PM10 increase resulted in a 2.04% and 8.28% morbidity increase. For lung cancer (LC) and cardiovascular diseases (AMI, IHD, CCP), a maximum delay of 5–6 months was found. Three-month delay and an average growth of 1.51% was observed in the case of chronic obstructive pulmonary disease (COPD). Overall, these findings revealed that PM10 was and it is responsible for one-third of the diseases.

PM2.5 air pollution contributes to the burden of frailty

Frailty is common among older people and results in adverse health outcomes. We investigated whether exposure to PM_2.5 is associated with frailty. This cross-sectional study involved 20,606 community-dwelling participants aged ≥ 65 years, residing in New Taipei City, Taiwan. Analytic data included phenotypic frailty, disease burden by Charlson Comorbidity Index (CCI), urban or rural residence, and household income. PM_2.5 exposure was calculated from air quality monitoring records, with low exposure defined as the lowest quartile of the study population. 1,080 frail participants (5.2%) were older, predominantly female, had more comorbidities, lived rurally, and had low PM_2.5 exposure (all p < 0.001). In multinomial logistic regression analyses, the likelihood of high PM_2.5 exposure was higher in prefrail (OR 1.4, 95% CI 1.3–1.5) and frail adults (OR 1.5, 95% CI 1.2–1.9) than in robust individuals, with stronger associations in those who were male (frail: OR 2.1, 95% CI 1.5–3.1; prefrail: OR 2.2, 95% CI 1.9–2.6), ≥ 75 years old (frail: OR 1.8, 95% CI 1.3–2.4; prefrail: OR 1.5, 95% CI 1.3–1.8), non-smokers (frail: OR 1.6, 95% CI 1.3–2.0; prefrail: OR 1.4, 95% CI 1.2–1.5), had CCI ≥ 2 (frail: OR 5.1, 95% CI 2.1–12.6; prefrail: OR 2.1, 95% CI 1.2–3.8), and with low household income (frail: OR 4.0, 95% CI 2.8–5.8; prefrail: OR 2.7, 95% CI 2.2–3.3). This study revealed a significant association between PM_2.5 exposure and frailty, with a stronger effect in vulnerable groups.

The association between city-level air pollution and frailty among the elderly population in China

A growing body of research suggests that air pollution negatively affects specific health outcomes, but how long- and short-term exposure to air pollution are associated with frailty is unclear. Using longitudinal data from adults aged 65 and over from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) linked with air quality index data, we model a frailty score according to the city-level of air pollution exposure, adjusting for individual socio-demographic factors and city-level indicators. All models show increased frailty with higher exposure to air pollution in one year prior to the interview, when controlling for short-term fluctuations. Moreover, elderly people living in areas where air pollution increased over the follow-up had larger increases in frailty scores than those where air pollution was relatively constant. The results suggest that air pollution plays a role in healthy ageing.

Frailty syndrome, biomarkers and environmental factors - A pilot study

Frailty is an age-related syndrome expected to increase over the next decades. This syndrome has been identified to be the most common condition leading to disability, institutionalisation and death in the elderly. The aim of this pilot study is to investigate a possible link between frailty status, biomarkers and environmental exposures. A group of 71 older adults (≥65 years old) was engaged in this study. The study population was classified as 45.1% robust, 45.1% pre-frail and 9.8% frail. A significant higher prevalence of second-hand smokers was found in the pre-frail group when compared to robust. Furthermore, a higher prevalence of robust individuals was found among those consuming home-produced vegetables and water from well/springs. Significant differences were found between data collected in a lifetime exposure questionnaire (LTEQ) and the levels of genotoxicity endpoints and the mercury levels analysed regarding some exposure-related parameters, namely, smoking habits, intake of home-produced vegetables and the use of pesticides in agriculture. Understanding if the way we live(d) or worked can impact the way we age are important questions to be explored. Data obtained in this pilot study encourage further studies on this matter, exploring the role of exposures history and its impact on health.

The interplay of haze characteristics on mortality in the Pearl River Delta of China

To estimate the mortality risk from haze and the modifying effects by three characteristics of haze (intensity, duration and timing), data on haze and mortality in the Pearl River Delta region from 2013 to 2016 were collected. We first estimated mortality risk during haze days compared with non-haze days. Then we classified haze into several categories by considering one or any two of the three haze characteristics together, and further calculated the mortality risks separately. The mortality risk increased 5.0% (95% confidence intervals (CI): 3.1%-6.9%) during hazy days compared with non-haze days, with larger effect for the elderly ≥ 85 years old (Excess risk (ER): 8.7%, 95% CI: 3.9%-13.6%) than other age groups. Mortality risk increased in longer haze (ER: 4.4%, 95% CI: 2.9%-6.0%) compared with shorter haze (ER: 1.9%, 95% CI: 0.7%-3.2%). The greatest effect of any two of haze characteristics was observed when haze was intense and long (ER: 4.8%, 95% CI: 3.0%-6.6%). Our study indicates that haze significantly increased mortality risk in the Pearl River Delta. The health effects of haze may be under-estimated when using a single air pollutant concentration during haze periods to assess health risk of haze events. The haze intensity, duration, and time of occurrence should be accounted for in appropriate risk assessment of haze.

Elderly Mortality and Exposure to Fine Particulate Matter and Ozone

BACKGROUND

The effects on particulate matter (PM) and ozone on health are being reported by a number of studies. The effects of these air pollutants are likely to be stronger in the elderly population, but studies in this regard are scarce. The purpose of this study was to study the effects of PM ≤ 2.5 μ and ozone on chronic health effects of the elderly population.

METHODS

In order to analyze the health status of the elderly population, National Statistical Office Mortality records were used. In this study, we calculated the number of deaths in Seoul of people who were 60 years or older between 2002 and 2012. The current study analyzed each disorder separately and the lag effect. PM and ozone were analyzed using the single exposure model, as well as the adjusted multi exposure model.

RESULTS

In the single exposure analysis with PM2.5 as the exposure variable, with the increase of 10 μ/m³, the number of deaths increased by 1.0039 fold, and vascular disease 1.0053 fold. In the multi exposure model adjusting for ozone, the number of deaths increased by 1.0037 fold, and vascular disease 1.0049 fold. In the single exposure analysis with ozone as the exposure variable, with the increase of 10 ppb, the number of deaths increased by 1.0038 fold, and in the multi exposure model adjusting for PM2.5, the number of deaths increased by 1.0027 fold. These results differed depending on the period or season. There was a 5-day lag effect between PM2.5 and deaths in the multi exposure model, and 1.0028 fold when adjusted for ozone. There was a 1-day lag effect in single exposure models with ozone as the main variable, and 1.0027 fold increase in deaths.

CONCLUSION

In our study, an increase in the number of deaths in the elderly population in accordance with the increase in the PM2.5 and ozone was found. The association found in our study could also influence socioeconomic burden. Future studies need to be performed in regards to younger population, as well as other air pollutants.

Effect of outdoor particulate air pollution on FEV1 in healthy adults: a systematic review and meta-analysis

The effect of acute and long-term exposures to outdoor particulate air pollution on lung function in healthy adults is not well established. The objective of this study was to conduct a systematic literature review and meta-analysis of studies that assessed the relationship of outdoor particulate air pollution and lung function in healthy adults. Studies that contained data on outdoor air particulate matter levels (PM₁₀ or PM_2.5) and forced expiratory volume in 1 s (FEV₁) in healthy adults were eligible for inclusion. Effect estimates, in relation to long-term and acute exposures, were quantified separately using random effects models. A total of 27 effect estimates from 23 studies were included in this review. Acute exposures were typically assessed with PM_2.5, while long-term exposures were predominantly represented by PM₁₀ A 10 µg/m3 increase in short-term PM_2.5 exposure (days) was associated with a -7.02 mL (95% CI -11.75 to -2.29) change in FEV₁ A 10 µg/m³ difference in long-term PM₁₀ exposure was associated with a -8.72 mL (95% CI -15.39 to -2.07) annual change in FEV₁ and an absolute difference in FEV₁ of -71.36 mL (95% CI -134.47 to -8.24). This study provides evidence that acute and long-term exposure to outdoor particulate air pollution are associated with decreased FEV₁ in healthy adults. Residual confounding from other risk factors, such as smoking, may explain some of the effect for long-term exposures. More studies are required to determine the relationship of long-term exposure to PM_2.5 and short-term exposure to PM₁₀, which may have different biologic mechanisms.

Lung health in older adults

One in five people in the UK live with lung disease. The National Taskforce for Lung Health, supported by 29 organisations, published its report in December 2018 with 43 recommendations for the UK, most of which are highly relevant to older adults. Prevention is key, especially relating to the introduction of clean air zones and air pollution alerts. Older adults may be even more prone to the adverse effects of particulate matter. Earlier and accurate diagnosis could improve survival for lung cancer, as well as health status for patients with chronic obstructive pulmonary disease (COPD) and related conditions. Currently, less than half of patients on inhalers receive an annual check, and there are one in five patients with COPD who should be on home oxygen but are not. By contrast, one in three people on oxygen do not benefit. Social isolation is common in people with lung disease, who would benefit from a personalised care plan and better access to pulmonary rehabilitation, which is also of benefit to those who are frail. Patients with lung diseases are much less likely to have conversations about advance care planning than in other conditions, probably because of the unpredictable nature of their illness, and variability of symptoms. The taskforce recommends that all healthcare professionals should be able to offer basic end of life advice.

Age modification of ozone associations with cardiovascular disease risk in adults: a potential role for soluble P-selectin and blood pressure

Background

Studies have suggested that age increases susceptibility to ozone-associated mortality, but the underlying mechanisms are unclear. In a previous study, personal exposure to ozone was significantly associated with a platelet activation biomarker, plasma soluble P-selectin (sCD62P), and blood pressure in 89 healthy adults, aged 22-52 years. The present study examines whether age modifies these associations in the same adults and in additional adults.

Methods

Interaction terms of age and exposure were analyzed using hierarchical Bayesian mixed effects ridge regressions. Data from a similar additional study involving 71 healthy participants, aged 19-26 years, were pooled with the data from the first study to evaluate age effect modification when more young adults were added to the analysis.

Results

In the 89 adults, significant age interactions were observed for past 24-hour and 2-week ozone exposures and sCD62P. Based on the pooled data (89 plus 71 adults), a 10 ppb increase in 24-hour ozone exposure was associated with increases in sCD62P and systolic blood pressure (SBP) by 22.3% (95% CI: 14.3%, 31.2%) and 1.35 (-0.18, 2.84) mmHg, respectively, at age 25; these values increased to 48.6% (32.7%, 65.1%) and 4.98 (2.56, 7.35) mmHg, respectively, at age 40.

Conclusions

These results mechanistically suggest that increasing age enhances cardiovascular effects of ozone.

Outdoor air pollution and mosaic loss of chromosome Y in older men from the Cardiovascular Health Study

BACKGROUND

Mosaic loss of chromosome Y (mLOY) can occur in a fraction of cells as men age, which is potentially linked to increased mortality risk. Smoking is related to mLOY; however, the contribution of air pollution is unclear.

OBJECTIVE

We investigated whether exposure to outdoor air pollution, age, and smoking were associated with mLOY.

METHODS

We analyzed baseline (1989-1993) blood samples from 933 men ≥65 years of age from the prospective Cardiovascular Health Study. Particulate matter ≤10 μm (PM₁₀), carbon monoxide, nitrogen dioxide, sulfur dioxide, and ozone data were obtained from the U.S. EPA Aerometric Information Retrieval System for the year prior to baseline. Inverse-distance weighted air monitor data were used to estimate each participants' monthly residential exposure. mLOY was detected with standard methods using signal intensity (median log-R ratio (mLRR)) of the male-specific chromosome Y regions from Illumina array data. Linear regression models were used to evaluate relations between mean exposure in the prior year, age, smoking and continuous mLRR.

RESULTS

Increased PM₁₀ was associated with mLOY, namely decreased mLRR (p-trend = 0.03). Compared with the lowest tertile (≤28.5 μg/m³), the middle (28.5-31.0 μg/m³; β = -0.0044, p = 0.09) and highest (≥31 μg/m³; β = -0.0054, p = 0.04) tertiles had decreased mLRR, adjusted for age, clinic, race/cohort, smoking status and pack-years. Additionally, increasing age (β = -0.00035, p = 0.06) and smoking pack-years (β = -0.00011, p = 1.4E-3) were associated with decreased mLRR, adjusted for each other and race/cohort. No significant associations were found for other pollutants.

CONCLUSIONS

PM₁₀ may increase leukocyte mLOY, a marker of genomic instability. The sample size was modest and replication is warranted.

Impacts of air pollution wave on years of life lost: A crucial way to communicate the health risks of air pollution to the public

Limited studies have explored the impacts of exposure to sustained high levels of air pollution (air pollution wave) on mortality. Given that the frequency, intensity and duration of air pollution wave has been increasing in highly polluted regions recently, understanding the impacts of air pollution wave is crucial. In this study, air pollution wave was defined as 2 or more consecutive days with air pollution index (API) > 100. The impacts of air pollution wave on years of life lost (YLL) due to non-accidental, cardiovascular and respiratory deaths were evaluated by considering both consecutive days with high levels of air pollution and daily air pollution levels in Tianjin, China, from 2006 to 2011. The results showed the durational effect of consecutive days with high levels of air pollution was substantial in addition to the effect of daily air pollution. For instance, the durational effect was related to an increase in YLL of 116.6 (95% CI: 4.8, 228.5) years from non-accidental deaths when the air pollution wave was sustained for 4 days, while the corresponding daily air pollution's effect was 121.2 (95% CI: 55.2, 187.1) years. A better interpretation of the health risks of air pollution wave is crucial for air pollution control policy making and public health interventions.

Air Pollution and Successful Aging: Recent Evidence and New Perspectives

PURPOSE OF REVIEW

Worldwide demographic changes occurring in a relatively short period have led to a growing interest in the determinants of aging "successfully" and how to promote a healthier old age. As environmental exposures such as ambient air pollution are believed to play a role in the process of aging, they might represent one of the pathways turning potential successful agers to unsuccessful agers. We aimed to critically review the current epidemiological evidence of the associations between chronic exposure to ambient air pollution and several key determinants of unsuccessful aging and to identify specific populations of unsuccessful agers that are potentially more vulnerable to air pollution's health effects.

RECENT FINDINGS

Epidemiologic evidence supports the association between air pollution and increased risk for several major chronic diseases, cognitive impairment, frailty, and decreased longevity-all important determinants of unsuccessful aging-as well as evidence for higher vulnerability among frail populations. However, several methodological shortcomings, including possible publication bias, lack of use of an adequate indicator of unsuccessful aging, limitations in exposure assessment, and residual confounding particularly due to socioeconomic status, hinder inference of causal relationship at this stage. Future studies should use constructs such as frailty index to estimate successful aging, as well as integrate time activity patterns into the exposure assessment metric. Additionally, studies in low- and middle-income countries are needed.

Associations between Ambient Particulate Matter and Nitrogen Dioxide and Chronic Obstructive Pulmonary Diseases in Adults and Effect Modification by Demographic and Lifestyle Factors

This study was undertaken to investigate the associations between chronic exposure to particulate matter of medium aerodynamic diameter ≤10 or ≤2.5 µm (PM10 or PM2.5) and nitrogen dioxide (NO₂) levels and lung function and to examine a possible change in these relationships by demographic and lifestyle factors. Chronic obstructive pulmonary disease (COPD) was defined using the Global Initiative for COPD criteria (forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) of <70%). Associations of lung function and COPD with PM10 or PM2.5 or NO₂ were examined using linear and logistic regression analyses among 1264 Korean adults. The highest tertiles of PM2.5 (≥37.1 μg/m³) and NO₂ (≥53.8 μg/m³) exposure were significantly associated with COPD (highest versus lowest tertile of PM2.5: adjusted odds ratio (OR) = 1.79, 95% CI: 1.02-3.13; highest versus lowest tertile of NO₂: adjusted OR = 1.83, 95% CI: 1.04-3.21). A 10 μg/m³ increase in PM10 concentration was associated with a 1.85 L (95% CI -3.65 to -0.05) decrease in FEV1 and a 1.73 L (95% CI -3.35 to -0.12) decrease in FVC, with the strongest negative association among older people and those with less education. Reduced lung function was associated with PM2.5 exposure in subjects with no physical activity. This study provides evidence that exposure to ambient air pollution has adverse effects on lung function in adults.

The short term burden of ambient fine particulate matter on chronic obstructive pulmonary disease in Ningbo, China

BACKGROUND

Numerous studies have found associations between ambient fine particulate matter (PM2.5) and increased mortality risk. However, little evidence is available on associations between PM2.5 and years of life lost (YLL). We aimed to estimate the YLL due to chronic obstructive pulmonary disease (COPD) mortality related to ambient PM2.5 exposure.

METHODS

A time-series study was conducted based on the data on air pollutants, meteorological conditions and 18,472 registered COPD deaths in Ningbo, China, 2011-2015. The effects of PM2.5 on YLL and daily death of COPD were estimated, after controlling long term trend, meteorological index and other confounders.

RESULTS

The impact of PM2.5 on YLL due to COPD lasted for 5 days (lag 0-4). Per 10 μg/m3 increase in PM2.5 was associated with 0.91 (95%CI: 0.16, 1.66) years increase in YLL. The excess YLL of COPD mortality were 8206 years, and 0.38 day per person in Ningbo from 2011 to 2015. The exposure-response curve of PM2.5 and YLL due to COPD showed a non-linear pattern, with relatively steep at low levels and flattened out at higher exposures.. Furthermore, the effects were significantly higher in the elderly than those in the younger.

CONCLUSIONS

Our findings explored burden of PM2.5 on YLL due to COPD and highlight the importance and urgency of ambient PM2.5 pollution control and protection of the vulnerable populations.

Susceptibility Factors Relevant for the Association Between Long-Term Air Pollution Exposure and Incident Asthma

In this review, we identified 15 studies in children and 10 studies in adults that assessed the association between long-term exposure to air pollution and incident asthma and that conducted stratified analyses to explore potential susceptibility factors. Overall, adult never-/former smokers seem to be at higher risk of incident asthma due to air pollution. Children without atopy and children from low socioeconomic status families also seem to be at higher risk of incident asthma due to air pollution. While interaction between air pollution and genes involved in the response to oxidative stress pathways have been explored, results are somewhat inconsistent and in need of replication. To evaluate interactions, large sample sizes are necessary, and much more research, including data pooling from existing studies, is needed to further explore susceptibility factors for asthma incidence due to long-term air pollution exposure.

Health Impact Assessment of a Predicted Air Quality Change by Moving Traffic from an Urban Ring Road into a Tunnel. The Case of Antwerp, Belgium

Background

The Antwerp ring road has a traffic density of 300,000 vehicles per day and borders the city center. The ‘Ringland project’ aims to change the current ‘open air ring road’ into a ‘filtered tunneled ring road’, putting the entire urban ring road into a tunnel and thus filtering air pollution. We conducted a health impact assessment (HIA) to quantify the possible benefit of a ‘filtered tunneled ring road’, as compared to the ‘open air ring road’ scenario, on air quality and its long-term health effects.

Materials and Methods

We modeled the change in annual ambient PM_2.5 and NO₂ concentrations by covering 15 kilometers of the Antwerp ring road in high resolution grids using the RIO-IFDM street canyon model. The exposure-response coefficients used were derived from a literature review: all-cause mortality, life expectancy, cardiopulmonary diseases and childhood Forced Vital Capacity development (FVC).

Results

Our model predicts changes between -1.5 and +2 μg/m³ in PM_2.5 within a 1,500 meter radius around the ring road, for the ‘filtered tunneled ring road’ scenario as compared to an ‘open air ring road’. These estimated annual changes were plotted against the population exposed to these differences. The calculated change of PM_2.5 is associated with an expected annual decrease of 21 deaths (95% CI 7 to 41). This corresponds with 11.5 deaths avoided per 100,000 inhabitants (95% CI 3.9–23) in the first 500 meters around the ring road every year. Of 356 schools in a 1,500 meter perimeter around the ring road changes between -10 NO₂ and + 0.17 μg/m³ were found, corresponding to FVC improvement of between 3 and 64ml among school-age children. The predicted decline in lung cancer mortality and incidence of acute myocardial infarction were both only 0.1 per 100,000 inhabitants or less.

Conclusion

The expected change in PM_2,5 and NO₂ by covering the entire urban ring road in Antwerp is associated with considerable health gains for the approximate 352,000 inhabitants living in a 1,500 meter perimeter around the current open air ring road.

Air quality of nursing homes and its effect on the lung health of elderly residents

In industrialized countries the elderly spend most of their time indoors. The elderly may be at a higher risk of suffering from indoor air pollution-related diseases compared to the rest of the population, because of their increased exposure to potential indoor risk factors. This editorial aims to critically analyze the recent literature regarding this important topic. Results of studies performed on the elderly living in nursing homes clearly highlight that they are at risk of respiratory health impairment, even at moderate air pollutant concentrations, particularly if they are over 80 years of age and living in poorly ventilated nursing homes. The future epidemiological research on ageing and respiratory diseases should investigate the underlying biological and physiological mechanisms, in addition to the adverse health effects of potential indoor risk factors, in order to help defining effective strategies for healthy ageing.

Long-term exposure to traffic emissions and fine particulate matter and lung function decline in the Framingham heart study

RATIONALE

Few studies have examined associations between long-term exposure to fine particulate matter (PM2.5) and lung function decline in adults.

OBJECTIVES

To determine if exposure to traffic and PM2.5 is associated with longitudinal changes in lung function in a population-based cohort in the Northeastern United States, where pollution levels are relatively low.

METHODS

FEV1 and FVC were measured up to two times between 1995 and 2011 among 6,339 participants of the Framingham Offspring or Third Generation studies. We tested associations between residential proximity to a major roadway and PM2.5 exposure in 2001 (estimated by a land-use model using satellite measurements of aerosol optical thickness) and lung function. We examined differences in average lung function using mixed-effects models and differences in lung function decline using linear regression models. Current smokers were excluded. Models were adjusted for age, sex, height, weight, pack-years, socioeconomic status indicators, cohort, time, season, and weather.

MEASUREMENTS AND MAIN RESULTS

Living less than 100 m from a major roadway was associated with a 23.2 ml (95% confidence interval [CI], -44.4 to -1.9) lower FEV1 and a 5.0 ml/yr (95% CI, -9.0 to -0.9) faster decline in FEV1 compared with more than 400 m. Each 2 μg/m(3) increase in average of PM2.5 was associated with a 13.5 ml (95% CI, -26.6 to -0.3) lower FEV1 and a 2.1 ml/yr (95% CI, -4.1 to -0.2) faster decline in FEV1. There were similar associations with FVC. Associations with FEV1/FVC ratio were weak or absent.

CONCLUSIONS

Long-term exposure to traffic and PM2.5, at relatively low levels, was associated with lower FEV1 and FVC and an accelerated rate of lung function decline.

Indoor air quality, ventilation and respiratory health in elderly residents living in nursing homes in Europe

Few data exist on respiratory effects of indoor air quality and comfort parameters in the elderly. In the context of the GERIE study, we investigated for the first time the relationships of these factors to respiratory morbidity among elderly people permanently living in nursing homes in seven European countries. 600 elderly people from 50 nursing homes underwent a medical examination and completed a standardised questionnaire. Air quality and comfort parameters were objectively assessed in situ in the nursing home. Mean concentrations of air pollutants did not exceed the existing standards. Forced expiratory volume in 1 s/forced vital capacity ratio was highly significantly related to elevated levels of particles with a 50% cut-off aerodynamic diameter of <0.1 µm (PM0.1) (adjusted OR 8.16, 95% CI 2.24-29.3) and nitrogen dioxide (aOR 3.74, 95% CI 1.06-13.1). Excess risks for usual breathlessness and cough were found with elevated PM10 (aOR 1.53 (95% CI 1.15-2.07) and aOR 1.73 (95% CI 1.17-10.3), respectively) and nitrogen dioxide (aOR 1.58 (95% CI 1.15-2.20) and aOR 1.56 (95% CI 1.03-2.41), respectively). Excess risks for wheeze in the past year were found with PM0.1 (aOR 2.82, 95% CI 1.15-7.02) and for chronic obstructive pulmonary disease and exhaled carbon monoxide with formaldehyde (aOR 3.49 (95% CI 1.17-10.3) and aOR 1.25 (95% CI 1.02-1.55), respectively). Breathlessness and cough were associated with higher carbon dioxide. Relative humidity was inversely related to wheeze in the past year and usual cough. Elderly subjects aged ≥80 years were at higher risk. Pollutant effects were more pronounced in the case of poor ventilation. Even at low levels, indoor air quality affected respiratory health in elderly people permanently living in nursing homes, with frailty increasing with age. The effects were modulated by ventilation.

Ozone exposure triggers insulin resistance through muscle c-Jun N-terminal kinase activation

A growing body of evidence suggests that exposure to traffic-related air pollution is a risk factor for type 2 diabetes. Ozone, a major photochemical pollutant in urban areas, is negatively associated with fasting glucose and insulin levels, but most aspects of this association remain to be elucidated. Using an environmentally realistic concentration (0.8 parts per million), we demonstrated that exposure of rats to ozone induced whole-body insulin resistance and oxidative stress, with associated endoplasmic reticulum (ER) stress, c-Jun N-terminal kinase (JNK) activation, and disruption of insulin signaling in skeletal muscle. Bronchoalveolar lavage fluids from ozone-treated rats reproduced this effect in C2C12 myotubes, suggesting that toxic lung mediators were responsible for the phenotype. Pretreatment with the chemical chaperone 4-phenylbutyric acid, the JNK inhibitor SP600125, or the antioxidant N-acetylcysteine alleviated insulin resistance, demonstrating that ozone sequentially triggered oxidative stress, ER stress, and JNK activation to impair insulin signaling in muscle. This study is the first to report that ozone plays a causative role in the development of insulin resistance, suggesting that it could boost the development of diabetes. We therefore provide a potential mechanism linking pollutant exposure and the increased incidence of metabolic diseases.

Adverse effects of outdoor pollution in the elderly

With fewer newborns and people living longer, older people are making up an increasing fraction of the total population. Epidemiological evidence shows that older-age-related health problems affect a wide and expanding proportion of the world population. One of the major epidemiological trends of this century is the rise of chronic diseases that affect more elderly than younger people. A total of 3.7 million premature deaths worldwide in 2012 are attributable to outdoor air pollution; the susceptibility to adverse effects of air pollution is expected to differ widely between people and within the same person, and also over time. Frailty history, a measure of multi-system decline, modifies cumulative associations between air pollution and lung function. Moreover, pre-existing diseases may determine susceptibility. In the elderly, due to comorbidity, exposure to air pollutants may even be fatal. Rapid and not-well-planned urbanization is associated with high level of ambient air pollution, mainly caused by vehicular exhausts. In general, there is sufficient evidence of the adverse effects related to short-term exposure, while fewer studies have addressed the longer-term health effects. Increased pollution exposures have been associated with increased mortality, hospital admissions/emergency-room visits, mainly due to exacerbations of chronic diseases or to respiratory tract infections (e.g., pneumonia). These effects may also be modulated by ambient temperature and many studies show that the elderly are mostly vulnerable to heat waves. The association between heat and mortality in the elderly is well-documented, while less is known regarding the associations with hospital admissions. Chronic exposure to elevated levels of air pollution has been related to the incidence of chronic obstructive pulmonary disease (COPD), chronic bronchitis (CB), asthma, and emphysema. There is also growing evidence suggesting adverse effects on lung function related to long-term exposure to ambient air pollution. Few studies have assessed long-term mortality in the elderly. It is still unclear what are the pollutants most damaging to the health of the elderly. It seems that elderly subjects are more vulnerable to particulate matter (PM) than to other pollutants, with particular effect on daily cardio-respiratory mortality and acute hospital admissions. Not many studies have targeted elderly people specifically, as well as specific respiratory morbidity. Most data have shown higher risks in the elderly compared to the rest of the population. Future epidemiological cohort studies need to keep investigating the health effects of air pollutants (mainly cardiopulmonary diseases) on the elderly.

Association of lead and cadmium exposure with frailty in US older adults

BACKGROUND

Environmental lead and cadmium exposure is associated with higher risk of several age-related chronic diseases, including cardiovascular disease, chronic kidney disease and osteoporosis. These diseases may lead to frailty, a geriatric syndrome characterized by diminished physiologic reserve in multiple systems with decreased ability to cope with acute stressors. However, no previous study has evaluated the association between lead or cadmium exposure and frailty.

METHODS

Cross-sectional study among individuals aged ≥ 60 years who participated in the third U.S. National Health and Nutrition Examination Survey and had either blood lead (N=5272) or urine cadmium (N=4887) determinations. Frailty was ascertained with a slight modification of the Fried criteria, so that individuals meeting ≥ 3 of 5 pre-defined criteria (exhaustion, low body weight, low physical activity, weakness and slow walking speed), were considered as frail. The association between lead and cadmium with frailty was evaluated using logistic regression with adjustment for relevant confounders.

RESULTS

Median (intertertile range) concentrations of blood lead and urine cadmium were 3.9 µg/dl (2.9-4.9) and 0.62 µg/l (0.41-0.91), respectively. The prevalence of frailty was 7.1%. The adjusted odds ratios (95% confidence interval) of frailty comparing the second and third to the lowest tertile of blood lead were, respectively, 1.40 (0.96-2.04) and 1.75 (1.33-2.31). Lead concentrations were also associated with the frequency of exhaustion, weakness and slowness. The corresponding odds ratios (95% confidence interval) for cadmium were, respectively, 0.97 (0.68-1.39) and 1.55 (1.03-2.32), but this association did not hold after excluding participants with reduced glomerular filtration rate: 0.70 (0.43-1.14) and 1.09 (0.56-2.11), respectively.

CONCLUSIONS

In the US older adult population, blood lead but not urine cadmium concentrations showed a direct dose-response relationship with frailty. These findings support that lead exposure increases frailty in older adults.

Carbon loading in airway macrophages as a biomarker for individual exposure to particulate matter air pollution - A critical review

Exposure to particulate matter (PM) is associated with adverse health effects, including chronic lung diseases, lung cancer and cardiovascular disease. Personal exposure varies depending on the generation of particles locally, background levels, activity patterns and meteorology. Carbon loading in airway macrophages (AM) is a novel marker to assess personal exposure to combustion-derived particles. This review summarizes the published evidence and describes the validity and reliability of this marker with a focus on the technical aspects. Carbon loading in AM is reported in nine published studies assessing personal exposure to particulate air pollution. The carbon content is quantified by image analysis and is suggested to be suited to assess cumulative exposures. While there is some variation in study technique, these studies each indicate that internal AM carbon reflects either external exposure or important health effects. However, some uncertainty remains regarding potentially confounding materials within particles, the time frame of exposures that this technique reflects, and the optimal strategy to accurately quantify AM carbon. These aspects need to be clarified or optimized before applying this technique in larger populations.

Adult lung function and long-term air pollution exposure. ESCAPE: a multicentre cohort study and meta-analysis

The chronic impact of ambient air pollutants on lung function in adults is not fully understood. The objective of this study was to investigate the association of long-term exposure to ambient air pollution with lung function in adult participants from five cohorts in the European Study of Cohorts for Air Pollution Effects (ESCAPE).

Residential exposure to nitrogen oxides (NO₂, NO_x) and particulate matter (PM) was modelled and traffic indicators were assessed in a standardised manner. The spirometric parameters forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) from 7613 subjects were considered as outcomes. Cohort-specific results were combined using meta-analysis.

We did not observe an association of air pollution with longitudinal change in lung function, but we observed that a 10 μg·m⁻³ increase in NO₂ exposure was associated with lower levels of FEV₁ (−14.0 mL, 95% CI −25.8 to −2.1) and FVC (−14.9 mL, 95% CI −28.7 to −1.1). An increase of 10 μg·m⁻³ in PM₁₀, but not other PM metrics (PM_2.5, coarse fraction of PM, PM absorbance), was associated with a lower level of FEV₁ (−44.6 mL, 95% CI −85.4 to −3.8) and FVC (−59.0 mL, 95% CI −112.3 to −5.6). The associations were particularly strong in obese persons.

This study adds to the evidence for an adverse association of ambient air pollution with lung function in adults at very low levels in Europe.

The ESCAPE study finds that, even at very low levels, air pollution has adverse effects on lung function in adultshttp://ow.ly/A1ssB

Longitudinal effects of air pollution on exhaled nitric oxide: the Children's Health Study

OBJECTIVES

To assess the effects of long-term variations in ambient air pollutants on longitudinal changes in exhaled nitric oxide (FeNO), a potentially useful biomarker of eosinophilic airway inflammation, based on data from the southern California Children's Health Study.

METHODS

Based on a cohort of 1211 schoolchildren from eight Southern California communities with FeNO measurements in 2006-2007 and 2007-2008, regression models adjusted for short-term effects of air pollution were fitted to assess the association between changes in annual long-term exposures and changes in FeNO.

RESULTS

Increases in annual average concentrations of 24-h average NO2 and PM2.5 (scaled to the IQR of 1.8 ppb and 2.4 μg/m(3), respectively) were associated with a 2.29 ppb (CI 0.36 to 4.21; p=0.02) and a 4.94 ppb (CI 1.44 to 8.47; p=0.005) increase in FeNO, respectively, after adjustments for short-term effects of the respective pollutants. In contrast, changes in annual averages of PM10 and O3 were not significantly associated with changes in FeNO. These findings did not differ significantly by asthma status.

CONCLUSIONS

Changes in annual average exposure to current levels of ambient air pollutants are significantly associated with changes in FeNO levels in children, independent of short-term exposures and asthma status. Use of this biomarker in population-based epidemiological research has great potential for assessing the impact of changing real world mixtures of ambient air pollutants on children's respiratory health.

Breastfeeding as a modifier of the respiratory effects of air pollution in children

BACKGROUND

Breastfeeding and air pollution are both important factors for respiratory symptoms and asthma in children. Few studies have examined possible interaction between them on respiratory outcomes.

METHODS

We studied 31,049 Chinese children, ages 2-14 years old, from 25 elementary schools and 50 kindergartens in the Seven Northeastern Cities during 2008-2009. Parents or guardians completed questionnaires about the children's histories of respiratory conditions, risk factors, and feeding methods. Three-year average concentrations of particles with an aerodynamic diameter ≤ 10 µm, sulfur dioxide, nitrogen dioxides, and ozone were calculated from monitoring stations in 25 study districts. We used two-level logistic regressions to examine the effects of exposure, controlling for covariates.

RESULTS

Association of air pollution with childhood respiratory conditions was modified by breastfeeding. Compared with children who had been breastfed, those who were not exhibited consistently stronger effects of air pollution. Among non-breastfed children, odds ratios (ORs) per 10 µg/m increase in nitrogen dioxide were 1.40 (95% confidence interval = 1.19-1.64) for cough, 1.41 (1.16-1.71) for phlegm, 1.17 (1.00-1.36) for current wheeze, and 1.25 (1.07-1.46) for doctor-diagnosed asthma. For breastfed children, the ORs were 1.25 (1.09-1.43) for cough, 1.15 (0.99-1.34) for phlegm, 0.97 (0.87-1.08) for current wheeze, and 1.17 (1.05-1.32) for doctor-diagnosed asthma. Breastfeeding was more protective among younger children. Breastfeeding was also associated with reduced effects of passive smoke exposure in children.

CONCLUSION

Breastfeeding is associated with smaller associations between air pollution and respiratory conditions in children, suggesting that breastfeeding reduces susceptibility to the respiratory effects of pollutants.