Visual Impairment Is More Common in Parkinson's Disease and Is a Risk Factor for Poor Health Outcomes

Background: Visual impairment is associated with hip fracture, depression, anxiety, and dementia in the general population, and many causes of visual impairment are preventable or treatable with early detection. However, the prevalence, outcomes, and healthcare utilization patterns associated with visual impairment have not been examined in Parkinson's disease (PD).

Methods: We performed a cross-sectional analysis of all Medicare beneficiaries with complete data in 2014 and longitudinal analysis of beneficiaries with PD from 2010 to 2014. We used diagnosis and procedure codes to identify PD, visual impairment, eye exams, hip fracture, and neuropsychiatric disorders. We compared the prevalence of visual impairment using logistic regression and used Cox proportional hazards regression to examine visual impairment and incident hip fracture, depression, anxiety, dementia, and death. We also examined the frequency of eye exams in PD using repeated-measures logistic regression.

Results: Among 26,209,997 Medicare beneficiaries in 2014, visual impairment was significantly more prevalent in PD (1.7%) than non-PD (0.71%) (adjusted odds ratio, 1.60; 95% confidence interval [CI], 1.56-1.65). In a longitudinal cohort of 542,224 Medicare beneficiaries with PD, less than 60% had a yearly eye exam. Visual impairment associated with increased hazard of depression (hazard ratio [HR], 1.23; 95% CI, 1.14-1.32), anxiety (HR, 1.34; 95% CI, 1.24-1.43), dementia (HR, 1.28; 95% CI, 1.21-1.36), and death (HR, 1.49; 95% CI, 1.44-1.55).

Conclusion: Visual impairment is more common in PD than the general population and is associated with negative PD-related outcomes. Understanding the mechanisms for these relationships is important for guiding future interventions to improve health outcomes in PD. © 2020 International Parkinson and Movement Disorder Society.