ImportanceEvidence-based therapies to reduce atherosclerotic cardiovascular disease risk in adults with type 2 diabetes are underused in clinical practice.ObjectiveTo assess the effect of a coordinated, multifaceted intervention of assessment, education, and feedback vs usual care on the proportion of adults with type 2 diabetes and atherosclerotic cardiovascular disease prescribed all 3 groups of recommended, evidence-based therapies (high-intensity statins, angiotensin-converting enzyme inhibitors [ACEIs] or angiotensin receptor blockers [ARBs], and sodium-glucose cotransporter 2 [SGLT2] inhibitors and/or glucagon-like peptide 1 receptor agonists [GLP-1RAs]).Design, Setting, and ParticipantsCluster randomized clinical trial with 43 US cardiology clinics recruiting participants from July 2019 through May 2022 and follow-up through December 2022. The participants were adults with type 2 diabetes and atherosclerotic cardiovascular disease not already taking all 3 groups of evidence-based therapies.InterventionsAssessing local barriers, developing care pathways, coordinating care, educating clinicians, reporting data back to the clinics, and providing tools for participants (n = 459) vs usual care per practice guidelines (n = 590).Main Outcomes and MeasuresThe primary outcome was the proportion of participants prescribed all 3 groups of recommended therapies at 6 to 12 months after enrollment. The secondary outcomes included changes in atherosclerotic cardiovascular disease risk factors and a composite outcome of all-cause death or hospitalization for myocardial infarction, stroke, decompensated heart failure, or urgent revascularization (the trial was not powered to show these differences).ResultsOf 1049 participants enrolled (459 at 20 intervention clinics and 590 at 23 usual care clinics), the median age was 70 years and there were 338 women (32.2%), 173 Black participants (16.5%), and 90 Hispanic participants (8.6%). At the last follow-up visit (12 months for 97.3% of participants), those in the intervention group were more likely to be prescribed all 3 therapies (173/457 [37.9%]) vs the usual care group (85/588 [14.5%]), which is a difference of 23.4% (adjusted odds ratio [OR], 4.38 [95% CI, 2.49 to 7.71]; P < .001) and were more likely to be prescribed each of the 3 therapies (change from baseline in high-intensity statins from 66.5% to 70.7% for intervention vs from 58.2% to 56.8% for usual care [adjusted OR, 1.73; 95% CI, 1.06-2.83]; ACEIs or ARBs: from 75.1% to 81.4% for intervention vs from 69.6% to 68.4% for usual care [adjusted OR, 1.82; 95% CI, 1.14-2.91]; SGLT2 inhibitors and/or GLP-1RAs: from 12.3% to 60.4% for intervention vs from 14.5% to 35.5% for usual care [adjusted OR, 3.11; 95% CI, 2.08-4.64]). The intervention was not associated with changes in atherosclerotic cardiovascular disease risk factors. The composite secondary outcome occurred in 23 of 457 participants (5%) in the intervention group vs 40 of 588 participants (6.8%) in the usual care group (adjusted hazard ratio, 0.79 [95% CI, 0.46 to 1.33]).Conclusions and RelevanceA coordinated, multifaceted intervention increased prescription of 3 groups of evidence-based therapies in adults with type 2 diabetes and atherosclerotic cardiovascular disease.Trial RegistrationClinicalTrials.gov Identifier: NCT03936660