Burden of Herpes Zoster Among Patients with Psoriasis in the United States

Abstract

Introduction

Patients with psoriasis (PsO) are at increased risk of herpes zoster (HZ), but recent data on the incidence of HZ among patients with PsO and the impact of HZ on healthcare resource use (HRU) and costs for patients with PsO have not been described.

Methods

This retrospective, longitudinal, cohort study estimated HZ incidence in cohorts of adults with vs without PsO (PsO + vs PsO–) and HRU and costs among those with PsO, with vs without HZ (PsO + /HZ + vs PsO + /HZ–) using Optum’s de-identified Clinformatics Data Mart Database during 2015–2020. Patients with psoriatic arthritis were excluded from all four cohorts. Comparisons between cohorts used generalized linear models to adjust outcomes based on various baseline characteristics.

Results

The incidence rate of HZ was significantly higher in the PsO + (n = 144,115) vs PsO– (n = 23,837,237) cohorts at 11.35 vs 7.67 per 1000 patient-years; adjusted incidence rate ratio (aIRR): 1.21, 95% confidence interval (CI): 1.16–1.25. HRU (outpatient, emergency department, and inpatient) was significantly higher in the PsO + /HZ + (n = 1859) vs PsO + /HZ– (n = 78,664) cohorts during 1 month and 3 months after HZ diagnosis (e.g., outpatient visits during month: 2.83 vs 1.30 per patient; aIRR: 1.96; 95% CI 1.86–2.06). Mean all-cause costs were also significantly higher in the PsO + /HZ + vs PsO + /HZ– cohort during both month ($5020 vs $2715 per patient; adjusted cost difference: $1390; 95% CI $842–$1964) and 3 months ($12,305 vs $8256; adjusted cost difference: $1422; 95% CI $280–$2889) after HZ diagnosis.

Conclusion

These findings show the increased incidence of HZ among patients with PsO and the clinical and economic burdens of HZ in this population. Considering the high prevalence of PsO, insights into the impact of HZ in these patients provide valuable evidence to inform clinical decision-making.

Plain Language Summary

Psoriasis is an inflammatory condition that causes flaky, scaly skin. Herpes zoster (shingles) causes a painful rash, usually on the abdomen. However, recent data on the proportion of patients with psoriasis who develop herpes zoster is lacking. Furthermore, little is known about the healthcare resources that are used or the costs of care for patients with psoriasis who develop herpes zoster. We found that patients with psoriasis were 21% more likely to have herpes zoster than patients without psoriasis. Among patients with psoriasis, those who developed herpes zoster had twice as many doctor’s visits, 3 times as many emergency department visits, and twice as many inpatient hospital stays during the month after a herpes zoster diagnosis as patients without herpes zoster. This resulted in an additional cost of $1390 per patient with psoriasis and herpes zoster compared with those with psoriasis but without herpes zoster. Overall, patients with psoriasis are at increased risk of developing herpes zoster and the healthcare resource use and associated cost of treating herpes zoster in patients with psoriasis is substantial.