Circadian variation in onset of epistaxis: analysis of hospital admissions

Most nosebleeds seem to occur either in the morning or the evening, suggesting that nosebleeds follow a 24-hour (circadian) pattern similar to that of blood pressure, finds a study in this week's BMJ.

Manfredini and colleagues reviewed all cases of nosebleeds from 1 January 1992 to 31 December 1998 in the emergency department of St Anna Hospital in Ferrara, Italy. For each of the 1741 nosebleeds reported, the time of onset was calculated - either within a 30-minute range or, where this was not possible, a range of within three hours. The age, sex and details of any underlying diseases amongst these patients were also recorded.

The authors found a highly significant circadian rhythm for nosebleeds, with a primary peak in the morning (8.24am) and a smaller secondary peak in the evening. This pattern was similar in both men (8.12am) and women (8.44am) say the authors, but age had no influence on this pattern, they add.

It is interesting that this biphasic pattern closely resembles the circadian rhythm of blood pressure, say the authors, suggesting that blood pressure might trigger or contribute to nosebleeds. Other factors related to venous bleeding and that might also show circadian variation deserve further investigation, they conclude.

Contact:

Roberto Manfredini, Professor of Emergency Medicine University of Ferrara Medical School, Italy. Email: [email protected]