Researchers who studied 34,000 babies born in a 20-year period found that those with a rare disorder of the heart rhythm had a sharply increased risk of sudden death before their first birthday. The finding could lead to a screening test for high-risk children and reduce the toll of unexpected and unexplained deaths.
Doctors in Italy took electrocardiograms - measures of heart rhythm - on the third or fourth day of life in all babies born in nine maternity hospitals between 1976 and 1994. In the year after their birth, 34 of the babies died, 24 from sudden infant death syndrome.
The researchers found that babies who died of cot death had longer QT intervals - a measure of the heart's pumping action - than those who died of other causes or who lived. Those in whom the interval was longest (over 440 milliseconds) were at more than 40 times the risk of suffering a cot death.
Writing in the New England Journal of Medicine, the researchers say: "A prolonged QT interval in the first week of life represents an important risk factor and this information may be useful in the early identification of infants at risk of Sids [Sudden Infant Death Syndrome]."
They add that traditional factors such as sleeping on the front and smoking by the mother increase the risks by much less. Parents are now advised to lay babies on their backs to sleep with their feet touching the end of the cot, not to smoke and to ensure infants are not wearing too many clothes or covered by too many blankets. Cot deaths in Britain have halved since 1991, when this advice was issued. An editorial in the journal warns that it would be premature to give all newborn babies an ECG to measure their heart rhythm.
The UK Foundation for the Study of Infant Deaths urged caution. A spokesman said: "These are interesting results but any suggestion that neonatal screening should be undertaken is premature."Reuse content