Interindividual variability in the benefits of personal sound amplification products on speech perception in noise: A randomized cross-over clinical trial

OBJECTIVE: The aging population is prone to hearing loss, which has several adverse effects on quality of life, including difficulty following conversations in noisy environments. Personal Sound Amplification Products (PSAPs) are a less expensive, over-the-counter alternative to traditional, more expensive hearing aids. Although some studies have shown that PSAPs can mitigate hearing loss, the literature generally only addresses group differences without considering interindividual variability. This study aimed to 1) determine how PSAPs affect listening effort and speech perception in noise and 2) measure interindividual variability and identify contributing demographic and health factors. DESIGN: We used a cross-over design in which all participants were assigned to each condition. PARTICIPANTS: Twenty-eight adults aged 60 to 87 years with normal hearing and mild hearing loss fulfilled the study requirements. INTERVENTION: In one session, speech-in-noise perception tasks were performed without PSAPs, and in the other, the tasks were performed with bilateral PSAPs. The two sessions were separated by one week, and the order of the sessions was balanced across participants. MAIN OUTCOME MEASURES: In both sessions, participants performed the Quick speech-in-noise test and a word discrimination task in noise, in which their self-reported listening effort was measured. RESULTS: PSAPs use improved speech perception in noise in both tasks and reduced listening effort. There was considerable variability between individuals, with approximately 60-70% of participants showing benefit. Age, hearing and cognitive status were significant predictors of the benefits. CONCLUSION: Not all individuals may benefit from the effect of PSAPs to the same extent at their first use, and this depends on specific health and demographic factors, particularly age, hearing, and cognitive status. These results underscore the importance of demographic and health factors in assessing the benefits of hearing amplification in older adults. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05076045.