Varicella Zoster infection is not independently associated with ischemic or hemorrhagic stroke

Background: Previous studies have shown a correlation between having had a previous infection of Varicella Zoster and an increased risk of stroke, even in the absence of rash. Our goal was to further evaluate this correlation using a large, publicly available inpatient database, searching for patients who have had either shingles, a stroke, or both. Method: We used the National (Nationwide) Inpatient Sample (NIS) to assess for any correlation between active shingles and increased stroke risk, looking at patients who were admitted to an inpatient setting in 2016-2020. Univariate and multivariate analyses were performed, adjusting for comorbid conditions Results: A total of 4,115,724 patients ≥ 18 years old had a diagnosis of stroke. From them, 2.85% had a history of shingles vs 2.77% without a history of shingles (OR, 1.03; 95% CI, 0.97-1.09; p = 0.31). When comparing only for hemorrhagic stroke, the percentage of patients admitted who had a history of shingles was 0.89%, versus 0.74% of patients without a history of shingles (OR, 1.20; 95% CI, 1.09-1.33; p = <0.001). However, after multivariate analysis, this difference became statistically insignificant (OR: 0.91, CI: 0.85-1,05, p =0.32) Conclusion: We found no correlation between having a history of shingles and an increased risk of hemorrhagic or ischemic stroke over the five years we studied.