PO-05-167 THE BIDIRECTIONAL ASSOCIATION BETWEEN ATRIAL FIBRILLATION AND MYOCARDIAL INFARCTION IN THE FRAMINGHAM HEART STUDY

Abstract

Atrial fibrillation (AF) and myocardial infarction (MI) are major contributors to disease burden. Studies suggest a bidirectional association between AF and MI. 1) To assess the bidirectional association between MI and AF, 2) to describe temporality between MI and AF among Framingham Heart Study participants with new-onset AF/MI, 3) to examine the association between interim/prevalent MI/AF and mortality among new-onset AF/MI cases. For aim 1, we included participants aged ≥45 years attending exams between 1960-2019. Multivariable-adjusted Cox proportional hazards models were used to calculate hazards ratios (HR) and 95% confidence intervals (CI) for the association between prevalent/interim MI/AF and incident AF/MI. Interim AF/MI were included as time-varying variables. For aims 2 and 3, we included all participants aged ≥45 years developing AF/MI from 1960-2019. In new-onset AF cases, we assessed percentages of prevalent MI, concurrent MI (diagnosed on the same day), and no MI, at time of AF diagnosis. Multivariable-adjusted HRs (95% CIs) were calculated for the association between prevalent/interim MI and mortality among participants with new-onset AF. We performed corresponding analyses for new-onset MI cases, using AF as exposure. In 10,334 participants free of MI at baseline (56% female, mean age 54±7 years), incidence rates of MI according to AF status are shown in table. The risk of incident MI was higher with interim compared to no AF (table). In 10,488 participants free of AF at baseline (55% female, mean age 54±7 years), incidence rates of AF according to MI status are displayed in table. The risk of incident AF was higher with prevalent and interim MI compared to no MI (table). In the 1,847 participants developing AF during 1960-2019 (46% female, mean age 75±11 years), 15% had prevalent MI, 2% had concurrent MI, and 84% had no MI, at time of AF diagnosis. In the 1,091 participants developing MI (42% female, mean age 70±11 years), 9% had prevalent AF, 3% had concurrent AF, and 89% had no AF, at time of MI diagnosis. In participants with new-onset AF or MI, prevalent and interim MI or AF were associated with significantly greater mortality compared to only AF or MI (table). The risk of incident AF was greater in participants with MI compared to no MI. The risk of incident MI was higher in participants with AF compared to no AF. Co-existing AF and MI were associated with a greater mortality compared to only AF or MI.Tabled 1(PO-05-167)Study SampleExposureOutcomeIncidence Rate per 1,000 person-years (95% CI)Hazards Ratio (95% CI)P-valueAF-free participants (N=10,488)Prevalent MIIncident AF23 (19-27)1.72 (1.41-2.11)<0.0001Interim MI50 (42-60)4.36 (3.51-5.42)<0.0001No MI8 (7-8)1.00 (ref)--MI-free participants (N=10,334)Prevalent AFIncident MI11 (8-15)1.33 (0.95-1.87)0.10Interim AF20 (16-26)2.75 (2.06-3.66)<0.0001No AF5 (4-5)1.00 (ref)--New-onset AF cases (N=1,847)Prevalent MIAll-cause mortality159 (139-180)1.36 (1.17-1.58)<0.0001Interim MI202 (161-252)2.25 (1.71-2.98)<0.0001No MI103 (97-109)1.00 (ref)--New-onset MI cases (N=1,091)Prevalent AFAll-cause mortality191 (153-236)1.60 (1.26-2.02)<0.0001Interim AF170 (147-192)2.53 (2.09-3.07)<0.0001No AF78 (72-84)1.00 (ref)-- Open table in a new tab