{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T07:06:27Z","timestamp":1793516787256,"version":"4.5.0"},"reference-count":44,"publisher":"American Medical Association (AMA)","issue":"8","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Intern Med"],"published-print":{"date-parts":[[2026,8,1]]},"abstract":"<jats:sec id=\"ab-ioi260030-4\">\n                    <jats:title>Importance<\/jats:title>\n                    <jats:p>COVID-19 vaccines were previously shown to reduce risk of major adverse cardiovascular events (MACEs). Whether the 2024-2025 COVID-19 vaccine continues to reduce COVID-19\u2013associated MACEs in the context of evolving variants and widespread population immunity is unknown.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-5\">\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To determine whether the 2024-2025 COVID-19 vaccine is associated with reduced risk of COVID-19\u2013associated MACE.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-6\">\n                    <jats:title>Design, Setting, and Participants<\/jats:title>\n                    <jats:p>This cohort study was a target-trial emulation using US Department of Veterans Affairs (VA) electronic health records. Participants were veterans with vaccination encounters between September 3, 2024, and December 31, 2024.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-7\">\n                    <jats:title>Exposures<\/jats:title>\n                    <jats:p>Same-day coadministration of the 2024-2025 COVID-19 and influenza vaccines vs influenza vaccine alone.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-8\">\n                    <jats:title>Main Outcomes and Measures<\/jats:title>\n                    <jats:p>Composite end point of COVID-19\u2013associated MACE, defined as COVID-19\u2013associated cardiovascular death, myocardial infarction, stroke, or hospitalization for heart failure. Secondary outcomes included all-cause MACE, hospitalization, and death. Vaccine effectiveness (VE), calculated as 1 minus the\u2009risk ratio, and risk difference were estimated at 8 months using inverse probability weighting.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-9\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 1\u202f039\u202f659 participants who received influenza vaccine (mean [SD] age, 70.1 [12.4] years; 954\u202f341 [91.8%] men), 349\u202f085 received COVID-19 vaccine and 690\u202f574 did not. At 8 months, the COVID-19 vaccine was associated with lower risk of COVID-19\u2013associated MACE (VE, 37.7% [95% CI, 18.2%-54.9%]; risk difference per 10\u202f000 persons, 2.0 [95% CI, 0.9-3.7]). VE for COVID-19\u2212associated MACE was statistically significant only in individuals older than 75 years (VE, 50.7% [95% CI, 31.8%-65.6%]), a group that also experienced the largest absolute risk reduction (5.5 fewer events per 10\u202f000 individuals). No statistically significant vaccine effectiveness was observed among those younger than 65 years or aged 65 to 75 years. While VE for COVID-19\u2212associated MACE on the relative scale was statistically significant across subgroups of participants with and without comorbid health conditions, the absolute benefit was consistently and substantially greater for individuals with the comorbid health condition. Secondary analyses of all-cause MACE, all-cause hospitalization, and all-cause death suggested substantially larger absolute risk reductions (risk difference for all-cause MACE, 23.7 [95% CI, 14.1 to 34.7]).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-ioi260030-10\">\n                    <jats:title>Conclusions and Relevance<\/jats:title>\n                    <jats:p>In this cohort study, receipt of the 2024-2025 COVID-19 vaccine was associated with reduced risk of COVID-19\u2013associated MACE, with reductions most prominent in those 75 years or older and those with comorbidities. While the reduction in COVID-19\u2013associated MACE was modest, the substantially larger reduction in all-cause MACE suggests that the vaccine\u2019s protective association extends to the hidden burden of undetected SARS-CoV-2 and its sequelae.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1001\/jamainternmed.2026.1929","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T15:30:50Z","timestamp":1781537450000},"page":"988","source":"Crossref","is-referenced-by-count":5,"title":["2024-2025 COVID-19 Vaccine and Major Adverse Cardiovascular Events Among US Veterans"],"prefix":"10.1001","volume":"186","author":[{"given":"Miao","family":"Cai","sequence":"first","affiliation":[{"name":"Clinical Epidemiology Center, Research and Development Service, VA St Louis Health Care System, US Department of Veterans Affairs, St Louis, Missouri"},{"name":"Veterans Research and Education Foundation of St Louis, St Louis, 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