Abstract Background Hearing loss is increasingly recognized as a non‐motor manifestation of Parkinson's disease (PD), but its prevalence, characteristics, and underlying mechanisms remain unclear. This systematic review aims to evaluate the prevalence and characteristics of hearing loss in people with PD (PwPD). Methods PubMed, Embase, and Web of Science were searched without restrictions. Observational studies assessing hearing loss in PwPD using pure tone audiometry (PTA), speech audiometry (SA), or central auditory processing (CAP) tests were included. Random‐effects models were applied, and heterogeneity was examined by meta‐regression. Results Thirty‐five studies encompassing 1316 PwPD and 820 controls were included. Pooled prevalence indicated 73.9% (95% CI: 61.5%, 84.8%) of 1009 PwPD had hearing loss, with high‐frequency impairment (82.6%) more common than low‐frequency loss (45.1%). Compared with age matched controls, PwPD were 1.82 times more likely to experience hearing loss (odds ratio = 1.82; 95% CI: 1.19–2.78; PwPD = 599; healthy controls = 579). Older age and higher‐frequency testing predicted higher prevalence. SA results were inconsistent. CAP meta‐analyses revealed significant prolongation of brain stem auditory‐evoked potential wave III latency (standardized mean difference SMD = 0.51; 95% CI: 0.15–0.88), wave V latency (SMD = 0.73; 95% CI: 0.25–1.21), and I–V interpeak interval (SMD = 0.84; 95% CI: 0.41–1.27). Among late latency potentials, N200 latency (SMD = 0.60; 95% CI: 0.20–0.99) and P300 latency (SMD = 0.73; 95% CI: 0.49–0.98) were significantly delayed, while other components showed no group differences. Conclusions Hearing loss is common in PD, extending beyond age‐related decline and likely involving both peripheral and central pathways. It may represent an early non‐motor symptom and a marker of cognitive vulnerability. © 2026 International Parkinson and Movement Disorder Society.
Firouzabadi et al. (2026) studied this question.