The impact of air pollution on mortality risk in the older adults with Alzheimer's disease and related dementias (ADRD)
Year: 2021
Type: conference-abstract
Abstract: BACKGROUND AND AIM: Increasing evidence links fine particulate matter (PM₂.₅), nitrogen dioxide (NO₂) and ozone (O₃) to mortality risk. We aimed to investigate the long-term effects of PM₂.₅, NO₂, O₃ and oxidant (Ox) exposures on mortality in an elderly population with a hospitalization in which Alzheimer's disease or related dementias (ADRD) were coded. METHODS: Using nationwide fee-for-service Medicare Part A data, we constructed a population-based open cohort including beneficiaries (age ≥ 65 years) in the contiguous United States (2000-2016) who had an ADRD code during a hospital stay, and we followed them from the year after the first such hospitalization to the end of the study period or their death. We assigned annual averages of PM₂.₅, NO₂ and O₃ from hybrid high-resolution models, and oxidant level as Ox=[(1.07×NO₂) + (2.075×O₃)]/3.14 to each individual based on calendar year and ZIP code. We applied multiple-pollutant (PM₂.₅+NO₂+O₃; PM₂.₅+Ox) Cox proportional hazard models with time-varying exposures to estimate hazard ratios (HRs) for mortality, stratifying on individual risk factors and adjusting for zip-code level socioeconomic status, seasonal temperature and humidity. RESULTS:Our cohort consisted of 5,076,794 individuals hospitalized with an ADRD code, of whom 81.5% died during the study period. We found that annual exposure to both PM₂.₅ (1.003 (95% CI 1.001, 1.006) for an IQR increase (3.7 μg/m³)) and NO₂ (1.010 (95% CI 1.008, 1.013) for an IQR increase (13.9 ppb)) were associated with increased mortality but we didn’t detect an association with ozone. We also found a HR of 1.004 (95% CI 1.002, 1.006) for an IQR increase (4.8 ppb) in Ox. CONCLUSIONS:In a large nationwide cohort, we provide new evidence on the association between long-term exposure to pollutants and mortality among elderly with an ADRD diagnosis during hospitalization. The associations were smaller than mortality risks previously reported in the general Medicare population. KEYWORDS: Air pollution, Particulate matter, Long-term exposure, Environmental epidemiology, Mortality, Multi-pollutant
Source: ISEE Conference Abstracts
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3195882450