Circadian Variation In Acute Coronary Syndromes

Background: Studies have shown that a circadian rhythm may exist in the onset of acute coronary syndromes. More studies are needed in the Indian population to confirm the existence of this circadian variation and add to the existing literature in the Indian population. Methods: Two hundred twenty consecutive patients with acute coronary syndromes, admitted to the coronary care unit were included in the study. The time of onset of symptoms was noted into six categories of four hours each. Results: The statistical analysis of the data obtained showed that acute coronary syndromes was commonest from 4am to 8 am (35%, P valueConclusions The circadian variation in the time of onset of acute coronary syndromes in an Indian population is similar to data published in the western literature, with a peak in the early morning. This variation appears to be exaggerated in the treatment naïve-hypertensive population. Further research is needed to assess the cellular and neuro-hormonal mechanisms of this circadian variation and may have implications in therapeutics.