Patients with chronic lung disease are being denied intensive care treatment because doctors are too pessimistic about their chances, research suggests.A British Medical Journal study of 800 patients who had been admitted to intensive care to help them breathe has found survival rates were higher than doctors predicted. The implication is that patients might not be admitted, even though they would benefit from the treatment.

The syndrome under study, chronic obstructive pulmonary disease, which includes chronic bronchitis and emphysema, causes 30,000 deaths a year in the UK.

When patients have a COPD attack, they can benefit from intubation -- where a tube is put into their airway to help them breathe -- but they have to be admitted to intensive care so they can be sedated for the procedure. However, doctors may be unwilling to admit patients who have a poor prognosis.

Often, however, the survival rate is higher than pessimistic doctors believe. Some 62% of patients who were intubated were alive six months later, although doctors had forecast that less than half would survive that long. In the worst cases, the forecast was 10% survival at six months but 40% of patients lived this long.