A nation-wide research study in Taiwan based on health insurance records indicates that sudden loss of hearing might be an early sign of risk to stroke. In fact, this symptom may be able to predict the actual stroke two years before it happens.
According to a news release of the American Heart Association:
Five-year follow-up data on 1,423 patients hospitalized for an acute episode of sudden sensorineural hearing loss (SSNHL) showed they were more than one-and-a-half times more likely to suffer a stroke than a control group of 5,692 patients who had been hospitalized for an appendectomy.
8.7 % (621 patients) of all the study patients had strokes during the 5-year follow-up period. Of these, 12.7 % were diagnosed with SSNHL. Only 7.8 % of patients in the control group had stroke in the same follow-up period.
“The inner ear is especially sensitive to transient ischemia because of its high energy requirement and lack of adequate collateral blood supply…Consequently, sudden sensorineural hearing loss appears to be an early sign of impending anterior inferior cerebellar artery infarction.”
“suggest that SSNHL can be an early warning sign of impending stroke. [The authors] suggest that SSNHL patients should undergo a comprehensive hematologic and neurological examination to help clinicians identify those potentially at risk for stroke developing in the near future.”
However, the authors caution that the results are very preliminary. This is the first study to investigate the link between cardiovascular event and hearing loss. More extensive studies are necessary to confirm the findings of this study. Other factors related to stroke risks such tobacco use, body mass index, heredity, and the medical history of heart disease and hypertension should also be considered in future studies.
Hearing loss is not an uncommon condition. According to the Hearing Loss Association of America, one in ten Americans has a hearing loss. It may be due to a lot of causes namely infection, or structural damage due to tumors, ruptured eardrums, nerve damage. Some medications may also cause temporary hearing loss as side effects.
Herng-Ching Lin et al. Sudden Sensorineural Hearing Loss Increases the Risk of Stroke. A 5-Year Follow-Up Study: Stroke 26 June 2008.