CLINICAL AND ECONOMIC BURDEN OF HERPES ZOSTER IN PATIENTS WITH ASTHMA: A RETROSPECTIVE COHORT STUDY

Abstract

<h3>Introduction</h3> Herpes zoster (HZ) is caused by reactivation of the varicella zoster virus, typically involves a painful dermatomal rash, and may lead to complications. Patients with asthma may be at increased risk of HZ. This study estimated the incremental burden of HZ in patients with asthma. <h3>Methods</h3> This retrospective cohort study used healthcare claims data from Oct-2015 to Feb-2020. Adults (aged ≥18 years) with asthma were identified using ICD-10-CM codes and pharmacy claims and assigned to cohorts of asthma+HZ if they had an HZ diagnosis (index date) or asthma-only if not (index date assigned to match the timing of HZ index dates). Healthcare resource utilization (HRU) and cost outcomes were compared between cohorts, adjusting for baseline differences, using generalized linear models. <h3>Results</h3> The study cohorts included 8,129 patients with asthma+HZ and 334,404 with asthma-only. Mean (standard deviation) age was 61.4 (15.0) and 52.9 (17.8) years in the asthma+HZ and asthma-only cohorts, respectively, and the asthma+HZ cohort had higher comorbidity burden. HRU was higher in the month after index for the asthma+HZ cohort: adjusted incidence rate ratios comparing the number of inpatient, emergency department, and outpatient encounters in asthma+HZ vs asthma-only cohorts were 2.75 (95% confidence interval 2.44-3.09), 2.82 (2.59-3.06), and 1.86 (1.81-1.90), respectively. HRU was also higher at 12 months after index for the asthma+HZ cohort and costs were higher at 1 month and 12 months after index in the asthma+HZ cohort (Table 1). <h3>Conclusion</h3> HZ was associated with higher HRU and costs in adults with asthma after HZ diagnosis.