Faculty Bibliography

PURPOSE OF REVIEW/OBJECTIVE:Ambient air pollution is strongly linked to cardiovascular and respiratory diseases. We summarize available published evidence regarding similar associations with diabetes across the life course. RECENT FINDINGS/RESULTS:) exposure contributes to more than 200,000 deaths from diabetes annually. There is a growing body of literature linking air pollution exposure during childhood and adulthood with diabetes etiology and related cardiometabolic biomarkers. A small number of studies found that exposure to air pollution during pregnancy is associated with elevated gestational diabetes risk among mothers. Studies examining prenatal air pollution exposure and diabetes risk among the offspring, as well as potential transgenerational effects of air pollution exposure, are very limited thus far. This review provides insight into how air pollutants affect diabetes and other metabolic dysfunction-related diseases across the different life stages.

BACKGROUND:With the number of annual global travelers reaching 1.2 billion, many individuals encounter greater levels of air pollution when they travel abroad to megacities around the world. This study's objective was to determine if visits to cities abroad with greater levels of air pollution adversely impacts cardiopulmonary health. METHODS:Thirty-four non-smoking, adult, healthy participants who traveled abroad to selected cities from the NYC metropolitan area were pre-trained to measure lung function, blood pressure, heart rate/variability, and record symptoms before, during, and after traveling abroad. Outdoor PM2.5 concentrations were obtained from central monitors in each city. Associations between PM exposure concentrations and cardiopulmonary health endpoints were analyzed using a mixed effects statistical design. RESULTS:East and South Asian cities had significantly higher PM2.5 concentrations compared to pre-travel NYC PM2.5 levels, with maximum concentrations reaching 503 μg/m3. PM exposure-related associations for lung function were statistically significant and strongest between evening FEV1 and same day morning PM2.5 concentrations: a 10 μg/m3 increase in outdoor PM2.5 was associated with a mean decrease of 7 ml. Travel to a highly polluted city (PM2.5 > 100 μg/m3) was associated with a 209 ml reduction in evening FEV1 compared to a low polluted city (PM2.5 < 35 μg/m3). In general, participants who traveled to East and South Asian cities experienced increased respiratory symptoms/scores and changes in heart rate and heart rate variability. CONCLUSIONS:Exposure to increased levels of PM2.5 in cities abroad caused small but statistically significant acute changes in cardiopulmonary function and respiratory symptoms in healthy young adults. These data suggest that travel-related exposure to increased PM2.5 adversely impacts cardiopulmonary health, which may be particularly important for travelers with pre-existing respiratory or cardiac disease.

BACKGROUND:Recent experimental evidence suggests that nutritional supplementation can blunt adverse cardiopulmonary effects induced by acute air pollution exposure. However, whether usual individual dietary patterns can modify the association between long-term air pollution exposure and health outcomes have not been previously investigated. We assessed, in a large cohort with detailed diet information at the individual level, whether a Mediterranean diet modifies the association between long-term exposure to ambient air pollution and cardiovascular disease mortality risk. METHODS:air pollution at the residential census-tract level. The alternative Mediterranean Diet Index (aMED), which uses a 9-point scale to assess conformity with a Mediterranean-style diet, was constructed for each participant from information in cohort baseline dietary questionnaires. We evaluated mortality risks for cardiovascular disease (CVD), ischemic heart disease (IHD), cerebrovascular disease (CER), or cardiac arrest (CAR) associated with long-term air pollution exposure. Effect modification of the associations between exposure and the mortality outcomes by aMED was examined via interaction terms. RESULTS:, we found significant associations with CVD (HR=1.06; 95% CI: 1.04-1.08), and IHD (HR=1.08; 95% CI: 1.05-1.11). Analyses indicated that Mediterranean diet modified these relationships, as those with a higher aMED score had significantly lower rates of air pollution related mortality ( p interaction<0.05). CONCLUSIONS:Mediterranean diet reduced cardiovascular disease mortality risk related to longterm exposure to air pollutants in a large prospective U.S cohort. Increased consumption of foods rich in antioxidant compounds may aid in reducing the considerable disease burden associated with ambient air pollution.

Awareness of the human health impacts of exposure to air pollution is growing rapidly. For example, it has become evident that the adverse health effects of air pollution are more pronounced in disadvantaged populations. Policymakers in many jurisdictions have responded to this evidence by enacting initiatives that lead to lower concentrations of air pollutants, such as urban traffic restrictions. In this review, we focus on the interplay between advances in environmental exposure assessment and developments in policy. We highlight recent progress in the granular measurement of air pollutants and individual-level exposures, and how this has enabled focused local policy actions. Finally, we detail an illustrative study designed to link individual-level health-relevant exposures with economic, behavioral, biological, familial, and environmental variables.

Air pollution poses a great environmental risk to health. Outdoor fine particulate matter (PM_2.5) exposure is the fifth leading risk factor for death in the world, accounting for 4.2 million deaths and more than a hundred million disability-adjusted-life-years lost according to the Global Burden of Disease Report. The World Health Organization attributes 3.8 million additional deaths to Indoor air pollution. Air pollution can harm acutely, usually manifested by respiratory or cardiac symptoms, as well as chronically, potentially affecting every organ in the body. It can cause, complicate, or exacerbate many adverse health conditions. Tissue damage may result directly from pollutant toxicity, because fine and ultrafine particles can gain access to organs, or indirectly through systemic inflammatory processes. Susceptibility is partly under genetic and epigenetic regulation. Although air pollution affects people of all regions, ages, and social groups, it is likely to cause greater illness in those with heavy exposure and greater susceptibility. Persons are more vulnerable to air pollution if they have other illnesses or less social support. Harmful effects occur on a continuum of dosage and even at levels below air quality standards previously considered to be safe.

Although air pollution is well known to be harmful to the lung and airways, it can also damage most other organ systems of the body. It is estimated that about 500,000 lung cancer deaths and 1.6 million COPD deaths can be attributed to air pollution, but air pollution may also account for 19% of all cardiovascular deaths and 21% of all stroke deaths. Air pollution has been linked to other malignancies, such as bladder cancer and childhood leukemia. Lung development in childhood is stymied with exposure to air pollutants, and poor lung development in children predicts lung impairment in adults. Air pollution is associated with reduced cognitive function and increased risk of dementia. Particulate matter in the air (particulate matter with an aerodynamic diameter < 2.5 μm) is associated with delayed psychomotor development and lower child intelligence. Studies link air pollution with diabetes mellitus prevalence, morbidity, and mortality. Pollution affects the immune system and is associated with allergic rhinitis, allergic sensitization, and autoimmunity. It is also associated with osteoporosis and bone fractures, conjunctivitis, dry eye disease, blepharitis, inflammatory bowel disease, increased intravascular coagulation, and decreased glomerular filtration rate. Atopic and urticarial skin disease, acne, and skin aging are linked to air pollution. Air pollution is controllable and, therefore, many of these adverse health effects can be prevented.

Dhaka, the capital of Bangladesh, is among the most polluted cities in the world. This research evaluates seasonal patterns, day-of-week patterns, spatial gradients, and trends in PM_2.5 (< 2.5µm in aerodynamic diameter), PM₁₀ (< 10µm in aerodynamic diameter), and gaseous pollutants concentrations (SO₂, NO₂, CO, and O₃) monitored in Dhaka from 2013 to 2017. It expands on past work by considering multiple monitoring sites and air pollutants. Except for ozone, the average concentrations of these pollutants showed strong seasonal variation, with maximum during winter and minimum during monsoon, with the pollution concentration of PM_2.5 and PM₁₀ being roughly 5-6 fold higher during winter vs. monsoon. Our comparisons of the pollutant concentrations with Bangladesh-NAAQS and US-NAAQS limits analysis indicate particulate matter (PM_2.5 & PM₁₀) as the air pollutants of greatest concern, as they frequently exceeded the Bangladesh-NAAQS and US-NAAQS, especially during non-monsoon time. In contrast, gaseous pollutants reported far fewer exceedances throughout the study period. During the study period, the highest number of exceedances of NAAQS limits in Dhaka city (Darus-Salam site) found for PM_2.5 (72% of total study days), followed by PM₁₀ (40% of total study days), O₃ (1.7% of total study days), SO₂ (0.38% of total study days), and CO (0.25% of total study days). The trend analyses results showed statistically significant positive slopes over time for SO₂ [5.6 ppb yr^-1, 95% Confidence Interval (CI): 0.7, 10.5] and CO [0.32 ppm yr^-1, 95% CI: 0.01, 0.56] which suggest increase in brick kilns operation and high sulfur diesel use. Though the statistically non-significant annual decreasing slopes for PM_2.5 [-4.6 µg/m³ yr^-1, 95% CI: -12.7, 3.6] & PM₁₀ [-2.7 µg/m³ yr^-1, 95% CI: -7.9, 2.5] were observed during this study period, the PM_2.5 concentration is still too high (~82.0 µg/m³) and can cause severe impact on human health. Implications This study revealed key insights into air quality challenges across Dhaka, Bangladesh, indicating particulate matter (PM) as Dhaka's most serious air pollutant threat to human health. The results of these analyses indicate that there is a need for immediate further investigations, and action based on those investigations, including the conduct local epidemiological PM exposure-human health effects studies for this city, in order to determine the most public health effective interventions.