Prevalence and 5-year incidence of dual sensory impairment in an older Australian population

Purpose: To report prevalence and 5-year incidence of dual sensory impairment (DSI), and associated risk factors, in an older population.

Methods: We included 2015 Blue Mountains Hearing Study participants aged ≥55 years, examined between 1997 and 1999 (baseline) and 2002 and 2004. Hearing thresholds were measured with the use of pure-tone audiometry. Visual acuity was measured with a LogMar chart while the subject wore distance glasses, if they owned a pair. DSI was defined as combined presenting visual acuity (better eye) <20/40, and PTA(0.5-4 kHz) (better ear) >25 dB HL. The incidence of DSI was considered by the use of two at-risk subpopulations: (i) participants with no sensory impairment and; (ii) with one type of sensory impairment at baseline.

Results: The prevalence of DSI was 6% at baseline, increasing from 0% for ages <60 years to 26.8% for ages 80+ years (p for trend <.0001). Five-year DSI incidence was 1.6% in persons with no sensory impairment and 11.3% in those with a single sensory impairment, a 7-fold difference. Among participants with either no sensory impairment or a single sensory impairment at baseline, a significant age-related increase in incident DSI was found (p for trend <.0001 and .0004, respectively). Low education was a significant risk factor for DSI among those with no sensory impairment and those with single sensory impairment, multivariable-adjusted odds ratio (OR, 6.62; 95% confidence interval [95% CI], 1.79-24.4) and OR, 2.55 (95% CI, 1.36-4.79), respectively.

Conclusions: Aging population trends and the age-related prevalence and incidence of DSI support the implementation of collaborative efforts in service provision between hearing and vision professionals. Active case-finding among older persons with single-sensory impairments may help identify those with DSI and provide timely and appropriate services.