Association between cataract and ischemic stroke risk in middle-aged adults: a retrospective cohort study in Taiwan

This cohort study aimed to investigate whether patients with cataract had an increased risk of ischemic stroke in Taiwan.

This study was conducted using electronic health records from Taiwan's National Health Insurance Research Database (NHIRD) over an eight-year period (2013-2020). Patients aged 40-64 years with newly diagnosed cataract were selected as the cataract group. Patients who had at least one ophthalmology visit but no diagnosis of cataract were selected as the non-cataract group from the same database. Both cataract and non-cataract groups were matched for sex, age, and baseline comorbidities using a 1:1 propensity score matching. The risk of ischemic stroke was compared between the two groups using a Cox proportional hazards model, adjusting for potential confounders.

The cohort study included 649,404 patients in the cataract group and 649,404 patients in the non-cataract group. The mean age was 57 years, and approximately 41.3% were male in both groups. The incidence rates of ischemic stroke were 6.12 per 1000 person-years in the cataract group and 4.48 per 1000 person-years in the non-cataract group (incidence rate ratio = 1.37, 95% CI = 1.34-1.40, P < 0.001). After adjusting for potential confounders, the hazard ratio for ischemic stroke was 1.33 in patients with cataract when compared to those without cataract (95% CI = 1.30-1.36, P < 0.001).

Our cohort study found that patients with cataract aged 40-64 years had an increased risk of ischemic stroke. These findings highlight the importance of recognizing this elevated risk in patients with cataract.