Functional hearing difficulty in Alzheimer's disease: Selective links to verbal fluency and behavioral and psychological symptoms of dementia severity

Background Hearing loss is a well-established risk factor for dementia. However, the clinical relevance of everyday listening difficulties after the diagnosis of Alzheimer's disease (AD) remains insufficiently understood, particularly in relation to cognition and behavioral and psychological symptoms of dementia (BPSD). Functional hearing difficulty refers to perceived difficulties in everyday listening situations that are not fully captured by standard audiometric thresholds. Objective To examine the associations between caregiver-rated functional hearing difficulty, cognitive measures commonly used in clinical practice, and overall BPSD severity in patients with AD. Methods This single-center cross-sectional study included 101 patients with clinically diagnosed AD attending a memory clinic. Functional hearing difficulty was assessed using a caregiver-based structured interview. Associations with widely used cognitive measures and BPSD severity, operationalized as the Neuropsychiatric Inventory five-domain total score, were examined using regression models adjusted for relevant covariates. Results Greater functional hearing difficulty was selectively associated with poorer verbal fluency, whereas no significant associations were observed with other cognitive measures. Functional hearing difficulty was also associated with greater BPSD severity. Exploratory analyses showed a pattern statistically consistent with an indirect association via verbal fluency. Conclusions Caregiver-rated functional hearing difficulty was selectively linked to verbal fluency and BPSD severity in patients with AD. These findings suggest that functional hearing difficulty may capture communication-related cognitive processes relevant to everyday functioning beyond global disease severity, although longitudinal studies are needed to clarify temporal relationships.