Dual-Sensory Loss Impacts Older Adults’ Health

A study of over 2,000 older adults in Singapore has found that combined hearing and olfactory loss is surprisingly common, affecting more than one in five people aged 60 and above. This dual sensory impairment (DSI), particularly the combination of hearing and smell loss, is linked to greater difficulty with daily tasks and a trend toward higher healthcare costs. The research provides new data on the interconnected nature of sensory health in an aging population.

How the Study Measured Sensory Loss

Led by researchers Isabelle Nooteboom, Eva Fenwick, and Ryan E. K. Man, the study involved 2,048 Asian adults with an average age of 75.7. To avoid relying on self-report, the team used validated clinical tests to objectively measure three senses. Hearing was assessed with pure-tone audiometry. Vision was tested using logMAR charts. Olfactory function was measured with the Sniffin’ Sticks test, which evaluates odor identification. The team then defined three types of dual sensory impairment (DSI): vision + hearing, vision + smell, and hearing + smell.

Using data from the 2020 Singapore Census, they calculated prevalence rates adjusted for age, sex, and ethnicity. Regression models identified which factors were linked to each type of DSI, and analyzed their impact on quality of life, instrumental activities of daily living (IADLs), and annual healthcare costs.

Hearing and Smell Loss is the Most Common Combination

The prevalence figures were striking. The combination of hearing and olfactory impairment was by far the most frequent, affecting 21.7% of the population studied. Hearing loss paired with vision impairment was less common but still significant at 7.3%. The combination of vision and smell loss was rare, with a prevalence of just 1.0%.

The risk profile for the two most common types of DSI differed. For hearing and vision loss, the significant factors were simply older age and having multiple chronic health conditions. In contrast, hearing and smell loss was associated with a wider set of factors: older age, being male, living alone, and being a current smoker.

Dual Impairments Amplify Impact on Daily Life

The consequences of having two impaired senses were greater than the sum of their parts. Participants with both hearing and vision loss reported measurably lower health-related quality of life scores. They were also 2.39 times more likely to have a lower status in instrumental activities of daily living—tasks like managing medications, finances, and transportation.

The group with hearing and smell loss faced similar challenges in daily functioning, being 2.10 times more likely to have lower IADL status. This group also showed a non-significant trend toward incurring higher annual healthcare costs compared to those without dual sensory loss. These findings highlight the compounded disability that can arise when more than one sensory channel is compromised.

Connections to Broader Hearing Health

This study underscores that hearing loss rarely exists in isolation, especially for older adults. The strong link between hearing impairment and olfactory loss points to possible shared mechanisms, such as general neural degeneration or common vascular risk factors. For clinicians, this means a diagnosis of hearing loss should prompt consideration of other sensory evaluations, and vice versa. A comprehensive auditory system evaluation is a logical starting point, but this research suggests a broader sensory health assessment may be warranted.

Understanding these combined impairments is also relevant for conditions like tinnitus and hyperacusis. The brain’s response to sensory deprivation or distortion from hearing loss can influence sound tolerance disorders. For instance, research into hyperacusis and tinnitus in cochlear implant users explores how the auditory system adapts to altered input, a process that may be further complicated by additional sensory losses.

Implications for Screening and Care in Aging Societies

The practical implications of this research are clear. With hearing and smell loss affecting over a fifth of this older Asian population, targeted screening programs could be highly effective. Identifying individuals with one sensory loss—particularly older men who live alone or smoke—should trigger a check for a second impairment.

Early identification is important because dual sensory loss has measurable impacts on independence and quality of life. Proactive management could help mitigate these outcomes. This might include sensory aids, home modifications, and social support to reduce the risk associated with living alone. The trend toward higher healthcare costs in the hearing+smell loss group suggests that early, integrated interventions could also be cost-effective for health systems.

As the global population ages, these findings from Singapore offer a template for other multi-ethnic societies. Sensory impairments are often managed by separate medical specialties. This study argues for a more holistic, person-centered approach to sensory health in older adults, where the focus is on the combined functional impact rather than each sense in isolation.

Source: Nooteboom, I., Fenwick, E. & Man, R.E.K. Prevalence, risk factors, impact and health-care costs of dual sensory impairment in a multi-ethnic older Asian population. Sci Rep (2024). https://doi.org/10.1038/s41598-026-40484-9

This article is for informational purposes only. Consult a qualified professional for personalised advice.