Short-term and long-term health impacts of air pollution reductions from COVID-19 lockdowns in China and Europe: a modelling study.

BACKGROUND: Exposure to poor air quality leads to increased premature mortality from cardiovascular and respiratory diseases. Among the far-reaching implications of the ongoing COVID-19 pandemic, a substantial improvement in air quality was observed worldwide after the lockdowns imposed by many countries. We aimed to assess the implications of different lockdown measures on air pollution levels in Europe and China, as well as the short-term and long-term health impact. METHODS: For this modelling study, observations of fine particulate matter (PM2·5) concentrations from more than 2500 stations in Europe and China during 2016-20 were integrated with chemical transport model simulations to reconstruct PM2·5 fields at high spatiotemporal resolution. The health benefits, expressed as short-term and long-term avoided mortality from PM2·5 exposure associated with the interventions imposed to control the COVID-19 pandemic, were quantified on the basis of the latest epidemiological studies. To explore the long-term variability in air quality and associated premature mortality, we built different scenarios of economic recovery (immediate or gradual resumption of activities, a second outbreak in autumn, and permanent lockdown for the whole of 2020). FINDINGS: The lockdown interventions led to a reduction in population-weighted PM2·5 of 14·5 µg m-3 across China (-29·7%) and 2·2 µg m-3 across Europe (-17·1%), with unprecedented reductions of 40 µg m-3 in bimonthly mean PM2·5 in the areas most affected by COVID-19 in China. In the short term, an estimated 24 200 (95% CI 22 380-26 010) premature deaths were averted throughout China between Feb 1 and March 31, and an estimated 2190 (1960-2420) deaths were averted in Europe between Feb 21 and May 17. We also estimated a positive number of long-term avoided premature fatalities due to reduced PM2·5 concentrations, ranging from 76 400 (95% CI 62 600-86 900) to 287 000 (233 700-328 300) for China, and from 13 600 (11 900-15 300) to 29 500 (25 800-33 300) for Europe, depending on the future scenarios of economic recovery adopted. INTERPRETATION: These results indicate that lockdown interventions led to substantial reductions in PM2·5 concentrations in China and Europe. We estimated that tens of thousands of premature deaths from air pollution were avoided, although with significant differences observed in Europe and China. Our findings suggest that considerable improvements in air quality are achievable in both China and Europe when stringent emission control policies are adopted. FUNDING: None.

Risks and benefits of early treatment of acute myocardial infarction with an angiotensin-converting enzyme inhibitor in patients with a history of arterial hypertension: analysis of the GISSI-3 database.

BACKGROUND: Many trials have proved the benefits of early systematic treatment with angiotensin-converting enzyme inhibitors in patients with acute myocardial infarction (AMI). Pathophysiological studies, however, suggest potential harm in excessive reduction of blood pressure (BP) in hypertensive patients with ischemic heart disease. METHODS: We analyzed data from the GISSI-3 (Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto miocardico) trial to assess the effects of early treatment with angiotensin-converting enzyme inhibitors during AMI in patients with a history of hypertension compared with normotensive patients. The trial randomly assigned 19,394 patients to 6 weeks of lisinopril treatment or control, starting treatment within 24 hours of AMI onset. RESULTS: In the 10,661 normotensive patients, lisinopril significantly reduced lethal events, but in the 7362 hypertensive patients, a higher rate of lethal events was reported the first day of treatment, and the benefits only appeared subsequently. These results may be attributable to the subgroup of 1165 hypertensive patients with low baseline systolic BP (lower quintile, BP <120 mm Hg), in whom critical hypotension was more prone to develop after lisinopril treatment. In fact, these patients showed a higher mortality rate as the result of an excess of cardiogenic shock during the first day of lisinopril treatment (odds ratio 3.07, 95% CI 1.39-6.77) and a persistent, unfavorable death trend after 6 weeks. CONCLUSIONS: These data suggest that caution should be exercised when using lisinopril in the acute phase of a myocardial infarction in patients with a history of hypertension but low systolic BP at presentation.