Hearing loss may be a non-motor feature of Parkinson's disease in older people in Taiwan.

BACKGROUND AND PURPOSE: The aim of this study was to explore whether hearing loss is associated with the risk of Parkinson's disease in the elderly in Taiwan. METHODS: Using claims data of the Taiwan National Health Insurance Program, 4976 patients (aged 65 years or older) with newly diagnosed hearing loss from 2000 to 2010 were identified and 19 904 subjects without hearing loss were randomly selected as comparisons, frequency matched by sex, age and index year of diagnosing hearing loss. The incidence of Parkinson's disease by the end of 2010 and the associated risk factors were investigated. RESULTS: The incidence of Parkinson's disease in the hearing loss group was 1.77-fold higher than that in the non-hearing-loss group (3.11 vs. 1.76 per 1000 person-years). After controlling for confounding factors, the adjusted hazard ratio (HR) of Parkinson's disease was 1.53 (95% CI 1.17, 1.99) for the hearing loss group compared with the non-hearing-loss group. Male sex (HR = 1.33, 95% CI 1.02, 1.74), age (for each year, HR = 1.06, 95% CI 1.04, 1.09), hypertension (HR = 1.70, 95% CI 1.26, 2.30) and cerebrovascular disease (HR = 1.78, 95% CI 1.37, 2.32) were also significantly associated with the risk of Parkinson's disease. CONCLUSIONS: Hearing loss correlates with an increased risk of Parkinson's disease in the elderly. Further studies are needed to confirm whether hearing loss could be a non-motor feature of Parkinson's disease.