Exposure to ambient air pollution and its threat to human health is a global concern, especially in the elderly population. Therefore, more in-depth studies are required to understand the extent of the harmful effects of particulate matter (PM) based on duration and levels of exposure. An investigation was conducted to determine the association between short- (1–14 days), medium- (1, 3, and 6 months), and long-term (1, 2, and 3 years) exposure to air pollutants (PM_2.5 and PM₁₀) and cognitive function among Koreans (4175 participants, mean age 67.8 years, 55.2% women) aged over 50 years. Higher levels of PM_2.5 exposure for short to long term and PM₁₀ exposure for medium to long term were found to be associated with decreased cognitive function, as indicated by lower scores of the Mini-Mental State Examination adopted in Korean (K-MMSE). There were significant effect modifications by sex, age group, alcohol consumption, physical activity, and smoking status in the association between long-term PM_2.5 and PM₁₀ exposure and cognitive function. These findings, which underscore the importance of the efforts to reduce the exposure levels and durations of air pollutants, especially in the vulnerable elderly population, provide evidence for establishing more stringent policies for air pollution regulations.

Ambient air pollutants reportedly increase inflammatory responses associated with multiple chronic diseases. We investigated the effects of long-term exposure to ambient air pollution on high-sensitivity C-reactive protein (hs-CRP) using data from 60,581 participants enrolled in the Korean Genome and Epidemiology Study-Health Examinees Study between 2012 and 2017. Community Multiscale Air Quality System with surface data assimilation was used to estimate the participants’ exposure to criteria air pollutants based on geocoded residential addresses. Long-term exposure was defined as the 2-year moving average concentrations of PM₁₀, PM_2.5, SO₂, NO₂, and O₃. Multivariable linear and logistic regression models were utilized to estimate the percent changes in hs-CRP and odds ratios of systemic low-grade inflammation (hs-CRP > 3 mg/L) per interquartile range increment in air pollutants. We identified positive associations between hs-CRP and PM₁₀ (% changes: 3.75 [95% CI 2.68, 4.82]), PM_2.5 (3.68, [2.57, 4.81]), SO₂ (1.79, [1.10, 2.48]), and NO₂ (3.31, [2.12, 4.52]), while negative association was demonstrated for O₃ (−3.81, [−4.96, −2.65]). Elevated risks of low-grade inflammation were associated with PM₁₀ (odds ratio: 1.07 [95% CI 1.01, 1.13]), PM_2.5 (1.08 [1.02, 1.14]), and SO₂ (1.05 [1.01, 1.08]). The odds ratios reported indicated that the exposures might be risk factors for inflammatory conditions; however, they did not reflect strong associations. Our findings suggest that exposure to air pollutants may play a role in the inflammation process.

Objectives: To investigate the association of sarcopenia, exposure to medium-term to long-term ambient particulate matter 2.5 µm and 10 µm (PM_2.5and PM₁₀) pollution and cognitive function in a community-dwelling cohort of middle-aged and older adults in South Korea.Design: A community-based prospective cohort study.Setting: In the Korean Genome and Epidemiology Study (KoGES).Participants: The participants were drawn from the seventh follow-up visit conducted between 2015 and 2016 in the KoGES community-based Ansung cohort who had participated in an ageing substudy.Outcome measures: Cognitive function was evaluated by the Korean version of the Mini-Mental State Examination (K-MMSE) and decreased cognitive function was defined as a K-MMSE score of 23 or less.Results: Of the 2274 participants (mean age 70.1 years, 58.3% women and mean annual PM_2.5and PM₁₀levels of 30.7 and 52.2 μg/m³, respectively), 8.7% (n=197) were sarcopenic, 35.8% (n=814) were possible sarcopenic and 55.5% (n=1263) were non-sarcopenic. The predictors of sarcopenia included body mass index, cognitive function, age, marital status, hypertension and physical activity. Exposure to PM_2.5and PM₁₀for an average duration of 1 month to 3 years was not selected as a predictor of sarcopenia. Participants with sarcopenia were associated with lower cognitive scores (β=−1.51, p<0.0001) and decreased cognitive function compared with those without sarcopenia (OR 2.34, 95% CI 1.56 to 3.52). Exposure to medium-term and long-term PM_2.5or PM₁₀was not associated with sarcopenia. The effect modification of PM exposure on the association between sarcopenia and cognitive function was generally not detected.Conclusions: In this community-based observational cohort study of KoGES participants aged 50 years and older, sarcopenia was associated with decreased cognitive function. However, medium-term to long-term exposure to PM_2.5or PM₁₀was not associated with sarcopenia and did not modify the relationship between sarcopenia and cognitive function.