Background Comprehensive smoke-free laws have been followed by drops in hospitalisations for acute myocardial infarction (AMI), including in a study with 2 years follow-up for such a law in Uruguay.

Methods Multiple linear and negative binomial regressions for AMI admissions (ICD-10 code 121) from 37 hospitals for 2 years before and 4 years after Uruguay implemented a 100% nationwide smoke-free law.

Results Based on 11 135 cases, there was a significant drop of −30.9 AMI admissions/month (95% CI −49.8 to −11.8, p=0.002) following implementation of the smoke-free law. The effect of the law did not increase or decrease over time following implementation (p=0.234). This drop represented a 17% drop in AMI admissions following the law (IRR=0.829, 95% CI 0.743 to 0.925, p=0.001).

Conclusions Adding two more years of follow-up data confirmed that Uruguay's smoke-free law was followed by a substantial and sustained reduction in AMI hospitalisations.