Association between air pollutants and dementia risk in the elderly

Abstract

Background The aging rate in Taiwan is the second highest in the world. As the population ages quickly, the prevalence of dementia increases rapidly. There are some studies that have explored the association between air pollution and cognitive decline, but the association between air pollution and dementia has not been directly evaluated. Methods This was a case-control study comprising 249 Alzheimer's disease (AD) patients, 125 vascular dementia (VaD) patients, and 497 controls from three teaching hospitals in northern Taiwan from 2007 to 2010. Data of particulate matter <10 μm in diameter (PM 10 ) and ozone were obtained from the Taiwan Environmental Protection Administration for 12 and 14 years, respectively. Blood samples were collected to determine the apolipoprotein E ( APOE ) ɛ4 haplotype. Bayesian maximum entropy was used to estimate the individual exposure level of air pollutants, which was then tertiled for analysis. Conditional logistic regression models were used to estimate adjusted odds ratios (AORs) and 95% confidence intervals between the association of PM 10 and ozone exposure with AD and VaD risk. Results The highest tertile of PM 10 (≥49.23 μg/m 3 ) or ozone (≥21.56 ppb) exposure was associated with increased AD risk (highest vs. lowest tertile of PM 10 : AOR = 4.17; highest vs. lowest tertile of ozone: AOR = 2.00). Similar finding was observed for VaD. The association with AD and VaD risk remained for the highest tertile PM 10 exposure after stratification by APOE ɛ4 status and gender. Conclusions Long-term exposure to the highest tertile of PM 10 or ozone was significantly associated with an increased risk of AD and VaD.

Sex and genetic differences in the effects of acute diesel exhaust exposure on inflammation and oxidative stress in mouse brain

“…Developmental exposure to traffic-related air pollution has been reported to be associated with autism spectrum disorders in humans and in experimental animals (Volk et al 2013; Roberts et al 2013; Thirtamara Rajamani et al 2013; Allen et al 2014a; 2014b; Chang et al 2016). Furthermore, markers of neurodegenerative diseases appear to be increased upon air pollution exposure (Levesque et al 2011; Calderon-Garciduenas et al, 2004; 2012; 2016; Wu et al 2015). These findings thus suggest that age is a third important determinant which may modulate susceptibility to air pollution neurotoxicity.…”

Pathophysiologic relationship between Alzheimer's disease, cerebrovascular disease, and cardiovascular risk: A review and synthesis

“…Specifically, long‐term exposure to high ozone and high particulate matter in the air leads to increased risk for obesity, metabolic syndromes [190], and a host of CVDs [191] including myocardial ischemia and infarction, heart failure, arrhythmias, stroke, and increased cardiovascular mortality [192]. Recently, a dose–response relationship was found between longitudinal exposure to high concentrations of atmospheric particulate matter <10 μm in diameter and significantly increased risk of AD and VCID in industrial regions of Taiwan [193].…”

Clinical effects of air pollution on the central nervous system; a review

“…Long-term exposure (>12 years) to PM is associated with an increased risk for AD in the elderly (>60 years old). [18] Increases in annual PM 2.5 exposure are associated with time to first hospitalization for common neurodegenerative diseases (dementia, AD, and PD). [19] The associations between densely populated urban cities, poor socioeconomic environments, and high stress living conditions could potentially confound these relationships.…”

“…Long term O 3 exposure (14-years) is associated with increased risk for vascular dementia in the elderly. [18] Further, reduced exposure to O 3 is associated with decreased hospital admissions. [30] A study in Taiwan demonstrated that high O 3 concentration and particulate matter exposure were associated with a 211% and 138% increased risk of AD onset, respectively.…”