Multiple sensory impairment in older Asians takes toll on functional capacity, healthcare spending

One in five older adults in Singapore sustain multiple sensory impairment (MSI), which can lead to the loss of functional independence and mobility while imposing a substantial economic burden, according to the PIONEER study.

In a cohort of 2,057 Singaporeans (mean age 72.2 years, 53.1 percent female, 48.6 percent Chinese), the national census-adjusted prevalence rate for any MSI was 20.6 percent. The respective prevalence rates for unilateral, combination, and bilateral MSI were 1.2 percent, 12.2 percent, and 7.2 percent. [BMC Public Health 2024;24:1102]

Compared with individuals who had no sensory loss, those who had any MSI had significantly decreased mobility (6.8 percent; p=0.012), had poor functioning (odds ratio [OR], 3.31, 95 percent confidence interval [CI], 1.18–9.32; p=0.023), and increased healthcare costs (β, 4.67, 95 percent CI, 2.21–9.85; p<0.001). The same was true for those with unilateral/combination and bilateral MSI.

However, only individuals with bilateral MSI had significant reductions in health-related quality of life (HRQoL) compared with those who had no sensory impairment (5.5 percent; β, –0.05, 95 percent CI, –0.09 to –0.01; p=0.012).

MSI was defined as concomitant vision (visual acuity >0.3 logMAR), hearing (pure-tone air conduction average >25 dB), and olfactory (Sniffin’ Sticks test score <12) impairments across the spectrum of laterality (any, unilateral, combination of unilateral and bilateral, and bilateral). Risk factors included older age (per year increase: OR, 1.33, 95 percent CI, 1.25–1.42; p<0.001), male gender (OR, 2.84, 95 percent CI, 1.43–5.65; p=0.003), low socioeconomic status (OR, 6.15, 95 percent CI, 2.06–18.15; p=0.001), and smoking (OR, 4.91, 95 percent CI, 1.60–15.01; p=0.005).

“These findings provide much needed evidence that MSI is a significant health concern in Asia and emphasize the urgent need to incorporate routine multiple sensory screening (vision, hearing, and smell) in basic medical assessments for older individuals, so that early detection and interventions can be adopted to prevent, slow, or even reverse the development and progression of MSI to maintain functional independence and decrease economic burden in this growing segment of the population,” the investigators said.

Referencing evidence from existing research on the negative consequences of MSI, the investigators postulated that MSI, particularly hearing and vision loss, might contribute to social isolation, depression, poor nutrition, sedentary behaviour, and functional limitations. These could lead to frailty, accelerated cognitive decline, and poor HRQoL, they said. [J Gerontol A Biol Sci Med Sci 2019;74:890-896; J Gerontol A Biol Sci Med Sci 2022;77:2123-2132; JAMA Otolaryngol Head Neck Surg 2020;146:278-285]

“Given that sensory impairments can be preventable or at least delayed, early detection and intervention for hearing (hearing aids) and vision (eg, surgical removal of cataract, provision of glasses), and to a lesser extent smell loss (olfactory training) might help to alleviate loneliness and maintain positive well-being in later life by not restricting social participation which, in turn, can help decrease the risk of future frailty, cognitive impairment, and functional dependence, potentially improving their QoL and economic well-being,” the investigators explained.

The study had several limitations, including an incomplete sensory data that excluded taste and touch, reliance on participants’ memory to report medical history and falls, and the inability to conduct any cultural adaptation of the Sniffin’ Sticks test. The investigators also acknowledged that the HRQoL questionnaire was generic and might not have fully captured the impact of specific sensory impairments.

A follow-up study is being conducted in a bid to establish the value of multiple sensory deficits as a clinical biomarker identifying older adults at high risk of poor health outcomes who could be targeted for early intervention to prevent the onset of adverse outcomes.