Prevalence of electrocardiographic unrecognized myocardial infarction and its association with mortality

Background: Identifying unrecognizedmyocardial infarction (MI) is important for secondary prevention. The aim of this study is to determine the prevalence and correlates of unrecognizedMI and the associationwithmortality in the general population.

Methods: All participants >= 18 years participating in the Lifelines population, a three- generation Cohort Study and Biobank, were included (n= 152,180). Participants with unrecognized MI were matched with controls without MI (1: 2) based on age and gender. Unrecognized MI was defined when no history of MI was reported in combinationwith electrocardiographic (ECG) signs corresponding to MI. A history ofMIwas defined as a reported history of MI in combination with ECG signs and/ or the use of antithrombotic medication.

Results: MI was present in 1881(1.2%) of participants and was unrecognized in 431 (22.9%) participants. Under the age of 50 years, percentages of unrecognized MI relative to the total amount of MI were 34% and 55% in men and women respectively. Compared to recognized MI, classical cardiovascular risk factors were less prevalent in participants with unrecognized MI. During a median follow- up time of 5, 4 and 4 years, 4.4%, 6.4% and 2.2% of participants with unrecognizedMI, recognized MI and without MI died, respectively. In a multivariable logistic regression unrecognized MI was an independent predictor of death.

Conclusions: The prevalence of unrecognized MI is substantial and classical cardiovascular risk factors are less prevalent in participants with unrecognized MI. Nevertheless, unrecognized MI is associated with mortality. Risk stratification and early diagnosis is necessary to reduce the morbidity and mortality after MI. (C) 2017 Elsevier B. V. All rights reserved.