July 1, 2008

Sudden Hearing Loss Linked to Stroke

A study using Taiwanese medical insurance records suggests sudden loss of hearing might be an early sign of vulnerability to stroke, researchers say.

Hearing loss can foreshadow a cerebrovascular event by as much as two years, the study published in Stroke: Journal of the American Heart Association found.

Lead investigator Herng-Ching Lin, a professor at Taipei Medical University School of Health Care Administration, says five-year follow-up data on 1,423 patients hospitalized for an acute episode of sudden sensorineural hearing loss showed they were more than 1 1/2 times more likely to suffer a stroke than a control group of 5,692 patients who had been hospitalized for an appendectomy.

However, because insurance records may not have contained reliable information, such as correct diagnostic codes or other factors, the findings should be considered tentative, Lin says.

To the best of our knowledge, no study has investigated the incidence or risk of cerebrovascular diseases developing following the onset of sudden sensorineural hearing loss, Lin says in a statement. But because this is the first time any association has been suggested, and because there were many limitations in the data, the results need to be interpreted cautiously until additional independent studies are performed.