Impact of COVID-19 Lockdowns from 2019 to 2021 on Air Pollution and Ischemic Heart Disease

Background: The COVID-19 lockdown led to reduced human activities and emissions, improving urban air quality.Studies have linked air pollution to increased risk of cardiovascular disease (CVD).Epidemiological studies have shown an association of ambient air with increased risk of cardiovascular disease mortality and morbidity.This study examines the effect of reduced vehicle movement and improved air quality on ischemic heart disease (IHD) emergency department (ED) visits in Tbilisi, Georgia.Objectives: To assess the short-term effects of exposure to fine particulate matter (PM₂.₅,PM₁₀), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO) on IHD (ICD10 codes: I20, I21) during the 2020 lockdown, compared with the same periods in 2019 and 2021.Methods: This retrospective study analyzed ED visits for IHD (ICD-10 codes: I20, I21) and ambient air pollution data in Tbilisi, Georgia.The lockdown period (March 21-May 22, 2020) was compared to the same periods in 2019 and 2021 using a 7-day moving average and t-tests to assess mean differences.Results: A total of 5,694 IHD cases were recorded across all years -42.8% in 2019, 26.2% in 2020, and 31% in 2021.In 2020, compared to 2019, there were significant reductions in CO and SO₂ levels and in 7-day average hospital admissions (mean difference 15.49, 95% CI (13.41-17.58)).In 2021, air pollution levels and hospital admissions increased compared to 2020.Conclusions: The decline in CO and SO₂ during the 2020 lockdown coincided with a reduction in IHD admissions, although the difference was not statistically significant.In 2021, pollution levels and admissions rose, suggesting a link between air quality and cardiovascular health, highlighting the potential public health benefits of improved air quality.