Association of Circadian Rhythm with Myocardial Infarction

Abstract

Cardiovascular diseases are the world’s leading cause of death. Human physiologic activities and state during illness are under the control of circadian rhythm. The aim of the study was to determine the potential association of chronotype and daytime sleepiness with susceptibility to myocardial infarction. We conducted a case-control study on 200 patients hospitalized due to myocardial infarction and 200 healthy controls. Systematic information on the past and present medical history was obtained from all participants. Chronotype was assessed using the Morningness-Eveningness Questionnaire (MEQ), and daytime sleepiness was assessed by the Epworth Sleepiness Scale (ESS). The mean age of the study population was 64±13 years, and 54.5% were male. There was no significant difference in MEQ (58.88±6.52 vs. 58.46±7.78, p=0.601) or ESS (5 (interquartile range, IQR 4-7.5) vs. 6 (IQR 3-8), p=0.912) score between patients and controls. Nevertheless, we found statistically significant differences related to risk factors for cardiovascular diseases, such as hypertension, dyslipidemia, and diabetes mellitus. However, there was no association of MEQ and ESS score with myocardial infarction in the study population.

Keywords

• Cardiovascular diseases
• Circadian rhythm
• Myocardial infarction
• Cause of death
• Croatia