Influenza epidemiology and treatment in people with a visual disability: A retrospective cohort study

Visual disabilities (VD) are expected to rise with an aging population. Persons with VD experience a higher prevalence of chronic and acute diseases. Despite the significance of influenza to this population, there is limited data comparing influenza care disparities between those with VD and those without.

The study aimed to determine the influenza burden and associated healthcare utilization in individuals with VD compared to those without disabilities.

A retrospective cohort study was conducted using the Korean National Health Information Database, encompassing three influenza seasons (2011-2012 to 2013-2014). The influenza incidence and incidence rate ratio (IRR) was calculated. Adjusted IRRs were calculated using a zero-inflated Poisson model. We assessed the risk of admissions and 30-day post-influenza mortality, employing logistic regression or survival analysis.

A total of 504,374 patients (252,964 patients with VD and 251,410 controls) were followed for 1,471,480 person-years. The influenza incidence was higher in the VD cohort than in the control (8.8 vs. 7.8 cases per 1000 person-years). VD cohort had a higher influenza IRR (adjusted IRR 1·13, 95% confidence interval [CI] 1·02-1·25). Severe VD exhibited higher hospitalization risk (adjusted odds ratio [OR] 1·29, 95% CI 1·10-1·20) and increased medical costs. Severe VD was a significant risk factor for mortality (adjusted Hazard Ratio 1·89, 95% CI 1·04-3·45).

People with VD have a higher influenza incidence, while their outcomes are comparable to those without. Nevertheless, severe VD significantly contributes more to hospitalization, mortality, and medical costs than controls.