LARGER reserves of blood will be needed as the population ages, North-East researchers warned today.

A study published in the British Medical Journal predicts that, if present trends continue, hospitals in the North-East will need two per cent more blood next year and five per cent more by 2008.

In the long-term, Dr Jonathan Wallis, a consultant haemotologist at Newcastle's Freeman Hospital, predicted the outlook could be "much worse" because of population trends.

But Dr Wallis said he hoped advances in medical science could help plug the yawning gap.

The study recorded the use of nearly 10,000 units of red blood cells from 18 NHS hospital blood banks in the north of England over 28 days.

It showed that 52 per cent were given to medical patients, 41 per cent to surgical patients and six per cent to obstetric and gynaecology patients.

Demand for red blood cell transfusion increases with age and, in the study, the average age of a patient receiving an individual unit was 63.

Using these figures and applying them to future population growth, the authors calculated how much extra blood would be needed in the region.

The research suggested demand for units of red blood cell will steadily increase.

The study authors, led by Dr Wallis, stated: "Figures from this study may help in planning effective and efficient use of the available blood supply."

However, they warned the introduction of donor testing for variant Creutzfeldt Jakob Disease (vCJD) could have a major impact on donations.

Some estimates suggested that up to 50 per cent of active donors could be lost because of it.

The researchers concluded rates of red cell transfusion would rise steeply with advancing ages and ''small increases in the number of elderly people will have large effects on demand''