Association of age-related eye diseases with cognitive frailty in older adults: a population-based study

Background Age-related eye diseases and cognitive frailty (CF) are both important predictors of adverse health outcomes in older adults, however, little is known about their association. Aims To demonstrate the association between age-related eye diseases and cognitive frailty in a population of Iranian older adults. Methods In this cross-sectional, population-based study, we included 1136 individuals (female n = 514) aged 60 years and older (mean 68.8 ± 6.7 years) who participated in the second cycle of the Amirkola Health and Aging Project (AHAP) between 2016 and 2017. Cognitive function and frailty were evaluated based on Mini-Mental State Examination (MMSE) and the FRAIL scale respectively. Cognitive frailty was defined as coexistence of cognitive impairment (CI) and physical frailty (PF), excluding confirmed cases of dementia such as Alzheimer’s disease. Cataract, diabetic retinopathy (DR), age-related macular degeneration (AMD), elevated intraocular pressure (IOP ≥ 21 mmHg) and glaucoma suspects (vertical cup to disc ratio (VCDR) ≥ 0.6) were diagnosed based on standardized grading protocols. Associations between eye diseases and cognitive frailty were evaluated through binary logistic regression analysis. Results Overall, CI, PF and CF were observed in 257 (22.6%), 319 (28.1%) and 114 (10.0%) participants respectively. After adjusting for confounders and ophthalmic conditions, individuals with cataract were more likely to have CF (OR 1.66; p -value 0.043), while DR, AMD, elevated IOP and glaucoma suspects (OR 1.32, 1.62, 1.42, 1.36, respectively) were not significantly associated with CF. Furthermore, cataract was significantly associated with CI (OR 1.50; p -value 0.022), but not with frailty (OR 1.18; p -value 0.313). Conclusion Older adults with cataract were more likely to have cognitive frailty and cognitive impairment. This association demonstrates the implications of age-related eye diseases beyond ophthalmology and substantiates the need for further research involving cognitive frailty in the context of eye diseases and visual impairment.