June 29, 2008 - A new study conducted by Taiwanese researchers revealed that sudden hearing loss could be a warning sign of increased stroke risk later in life.
People hospitalised for sudden hearing loss had more strokes in the following five years than otherwise fit appendicitis patients.

The article, in the journal ‘Stroke’, hinted no cause why the hearing problem could be related to strokes.

Five-year follow-up information on 1,423 patients taken to hospital for an acute episode of sudden sensorineural hearing loss (SSNHL) pointed that those patients were 1.5 times more likely to suffer a stroke, as compared to a control group of 5,692 patients who had been taken into hospital for appendix removal
   
Lead investigator Herng-Ching Lin, PhD, Taipei Medical University School of Health Care Administration, Taipei City, Taiwan., said that these findings may not have contained reliable information as there is not a clear universal definition for SSNHL in the database that was reexamined.

Secondly, the database didn’t have data about severity of hearing loss, level of hearing recovery, tobacco usage, BMI, and the medical record of cardiovascular disease and atrial fibrillation -- all of which can contribute to stroke risk.

Dr. Lin stated, “To the best of our knowledge, no study has investigated the incidence or risk of cerebrovascular diseases following the onset of sudden sensorineural hearing loss.”

On the other hand, Dr. Lin recommend all SSNHL patients to undergo a comprehensive neurological exam and blood testing to gauge their risk profile for stroke.

Dr. Tony Rudd, a stroke specialist from Guy's and St Thomas' Hospital in London, said that while it was an "interesting association", the two might not turn out to be linked.

"It's an unusual finding, quite surprising, but not one that you hear, and immediately think makes sense," Rudd added.

He said that while stroke itself could cause hearing loss, this was "very rare", although patients who lost hearing because of blood supply problems to their inner ear might be investigated to see if similar problems could happen anywhere else.