Long-term air pollution exposure and incident dementia in American elderly population: a national cohort study
Year: 2021
Type: conference-abstract
Abstract: BACKGROUND AND AIM: Evidence links air pollution to increased risk of dementia or Alzheimer’s disease (AD). However, previous studies have focused on hospitalizations as the measure of morbidity, which is a poor measure of either incidence or prevalence for these conditions. In addition, neuropathologic changes are known to occur many years prior to the diagnosis, and the relevant time window in which air pollution might increase risk of dementia or AD remains unclear. METHODS: We conducted a national, population-based, cohort study to investigate the impact of long-term exposure to PM2.5, NO2, and O3 on dementia and AD incidence, using the nationwide Medicare population and high-resolution air pollution data. To better approximate dementia and AD incidence, we used a 5-year “clean” period and all Medicare claims nationwide (2000-2018), including Medicare inpatient and outpatient claims, carrier file (primarily doctor visits), skilled nursing facility, and home health-care claims. Cox proportional hazard models were fit to estimate hazard ratios (HRs) for dementia and AD incidence. RESULTS:Using annual average pollutant level 5 years prior to diagnosis, per interquartile range (IQR) increase in annual PM2.5 (3.7 µg/m3), annual NO2 (13.3 ppb), and warm-season O3 (7.2 ppb), the HRs were 1.050 (95% CI: 1.045, 1.055), 1.017 (95% CI: 1.011, 1.023), and 0.994 (95% CI: 0.991, 0.998) for incident dementias, and 1.087 (95% CI: 1.078, 1.097), 1.045 (95% CI: 1.035, 1.056), and 0.972 (95% CI: 0.965, 0.978) for incident AD, respectively. For both outcomes there was strong evidence of linearity in concentration-response relationships for PM2.5 and NO2, suggesting that no safe threshold exists for health-harmful pollution levels. CONCLUSIONS:Using a large nationwide cohort, we provide strong evidence that exposure to PM2.5 and NO2, but not O3, were significantly associated with an increased incidence of dementia and AD. Improving air quality may yield substantial health benefits by reducing the burden of neurological disorders. KEYWORDS: Air pollution, Dementia, Alzheimer's disease, incidence
Source: ISEE Conference Abstracts
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4233240719