A study published in Arch Neurol (2011) found that hearing loss is independently associated with an increased risk of incident all-cause dementia and Alzheimer's disease (AD). The study followed 639 participants aged 36–90 years from the Baltimore Longitudinal Study of Aging (BLSA) who had audiometric testing and were dementia-free in 1990–1994. Hearing loss was defined by pure-tone average (PTA) thresholds in the better-hearing ear, with normal hearing (PTA <25 dB), mild (25–40 dB), moderate (41–70 dB), and severe (>70 dB). Over a median follow-up of 11.9 years, 58 cases of all-cause dementia were diagnosed, of which 37 were AD. The risk of incident dementia increased log-linearly with the severity of baseline hearing loss. Compared to normal hearing, the hazard ratios for incident all-cause dementia were 1.89 for mild, 3.00 for moderate, and 4.94 for severe hearing loss. For AD, the hazard ratio increased with hearing loss but with a wider confidence interval. The study adjusted for age, sex, race, education, diabetes, smoking, and hypertension. The findings suggest that hearing loss may be a modifiable risk factor for dementia. The study also considered potential mechanisms, including cognitive reserve depletion, social isolation, and environmental deafferentation. However, the study had limitations, such as the lack of data on hearing loss trajectories and the potential for residual confounding. The results highlight the importance of addressing hearing loss in older adults to potentially reduce dementia risk. The study underscores the need for further research to determine whether hearing loss is a marker for early dementia or a modifiable risk factor.A study published in Arch Neurol (2011) found that hearing loss is independently associated with an increased risk of incident all-cause dementia and Alzheimer's disease (AD). The study followed 639 participants aged 36–90 years from the Baltimore Longitudinal Study of Aging (BLSA) who had audiometric testing and were dementia-free in 1990–1994. Hearing loss was defined by pure-tone average (PTA) thresholds in the better-hearing ear, with normal hearing (PTA <25 dB), mild (25–40 dB), moderate (41–70 dB), and severe (>70 dB). Over a median follow-up of 11.9 years, 58 cases of all-cause dementia were diagnosed, of which 37 were AD. The risk of incident dementia increased log-linearly with the severity of baseline hearing loss. Compared to normal hearing, the hazard ratios for incident all-cause dementia were 1.89 for mild, 3.00 for moderate, and 4.94 for severe hearing loss. For AD, the hazard ratio increased with hearing loss but with a wider confidence interval. The study adjusted for age, sex, race, education, diabetes, smoking, and hypertension. The findings suggest that hearing loss may be a modifiable risk factor for dementia. The study also considered potential mechanisms, including cognitive reserve depletion, social isolation, and environmental deafferentation. However, the study had limitations, such as the lack of data on hearing loss trajectories and the potential for residual confounding. The results highlight the importance of addressing hearing loss in older adults to potentially reduce dementia risk. The study underscores the need for further research to determine whether hearing loss is a marker for early dementia or a modifiable risk factor.