The official number of problem alcohol use cases being treated in Ireland has increased by 43% over the past six years, according to a new report.

However, the actual number of cases being treated by addiction services could be much greater than reported. One case does not necessarily represent one person as the same patient can have more than one treatment episode.

According to the report by the Health Research Board (HRB) there were 42,333 cases treated for problem alcohol use between 2005 and 2010. The numbers treated rose from 5,525 to 7,866 in that period.

ThHRB says the major rise in alcohol abuse treatment was partly due to improved reporting but also reflected a true increase in the number of people requiring treatment for problem alcohol use.

Half of the cases treated had started drinking by the time they were 16 and one-in-five cases reported problem drug use with other substances including cannabis, cocaine, ecstasy and benzodiazepines.

The report shows that half of all cases treated over the six-year period were under 39 and there was a 145% increase in new cases of alcohol problems in under 18s. Forty per cent of cases were drinking on a daily basis.

Dr Suzi Lyons of the HSE said given that some treatment services have yet to take part in the reporting system, the new figures underestimated the true extent of treated alcohol problems in Ireland.