The American Heart Association published a recap of an extensive study that establishes a relationship between sudden loss and stroke. This condition is marked, obviously, with the sudden onset of hearing loss, as in one day you hear fine and a week later you can't hear the TV anymore. So, we're not talking about the slow, gradual hearing loss associated with the ageing process. This is different. You hear. Then you don't. Very sudden.
The study, conducted in Taiwan, showed a clear relationship between the onset of sudden hearing loss and stroke. Published in Stroke: Journal of the American Heart Association, this important study "suggests that sudden loss of hearing might be an early sign of vulnerability to stroke, foreshadowing an actual cerebrovascular event [stroke] as much as two years [later]."
Study Parameters and Conclusions
The study, which took place over five years, tracked 1,423 patients who had been hospitalized for unexplained, acute, sudden hearing loss. Also included in the study as a control group [for comparison purposes] were 5,692 patients admitted for simple appendectomies.
The group reporting severe hearing loss was more than 150% more likely to experience a stroke within two years of the hearing loss when compared to the appendectomy control group.
Results Must be Interpreted with Care
Lead investigator, Herng-Ching Lin, Ph.D and professor at the Taipei Medical University School of Health Care Administration, urged caution in drawing too many conclusions too quickly.
"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 said. "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."
Dr. Lin continued. "Secondly, the database did not contain information regarding severity of hearing loss, extent of hearing recovery, tobacco use, body mass index and the medical history of cardiovascular disease and atrial fibrillation - all of which can contribute to stroke risk."
The data was incomplete with regard to other factors that affect hearing and the incidence of stroke. The authors report the need for further research into the relationship between sudden hearing loss and stroke.