Original paper
The effect of Ramadan fasting on circadian variation of Turkish patients with acute myocardial infarction

Introduction: The mechanisms of circadian variation in cardiovascular events are not clear.

Aim: Evaluation of the effect of Ramadan fasting on circadian variation of acute ST-elevation myocardial infarction (STEMI) in Turkish patients.

Material and methods: This comparative cross-sectional study included 151 consecutive patients with acute STEMI. The time of onset of STEMI was determined by the attending physician on the basis of patients’ self-reports. The patients were divided into two group based on the history of fasting. The standard hourly profile of the onset of STEMI was obtained over a 24-h period. Patients were then categorized into four 6-hour increments according to the time that the symptoms began (00:00–05:59; 06:00–11:59; 12:00–17:59 and 18:00–23:59 h).

Results: In all study participants, the highest incidence of STEMI was between 12.00 and 18.00; the odds ratio was 2.77 (95% CI: 2.63–2.92, p < 0.001). In the non-fasting group, the highest incidence of STEMI occurred between 06:00 and 12:00 A.M. The highest incidence of AMI occurred between 12.00 A.M. and 18.00 in patients with fasting; the odds ratio was 2.70 (95% CI: 2.51–2.91, p < 0.001). There were significant differences between fasting and non-fasting groups regarding circadian variation of STEMI (p < 0.001).

Conclusions: There are significant changes in the circadian variation of patients with STEMI in relation to Ramadan fasting.