Health and economic burden of herpes zoster in adults in Finland: A retrospective nationwide database study

The risk of herpes zoster (HZ) and its complications, such as postherpetic neuralgia (PHN), increases with age and burdens patients, the healthcare system, and society. We aimed to estimate the incidence, healthcare resource use (HCRU), and direct and indirect costs due to HZ and HZ-related complications (i.e. PHN) per age group in the adult population in Finland. This retrospective, non-interventional population-based registry study collected data from four different registers over 2014-2019: three with nationwide coverage and one with partial nationwide coverage. International classification codes were used to identify HZ and PHN cases. The incidences of HZ and PHN were stratified annually and per age group (18-49, 50-59, 60-64, 65-69, 70-79, ≥80 years of age [YoA]). The HZ-associated HCRU, and direct and indirect costs were estimated by counting healthcare contact, medications, and their unit costs from national registries. HZ incidence rate increased with age from 1.99/1,000 persons in 18-49 YoA to 8.04/1,000 persons in ≥80 YoA over 2014-2019. PHN incidence also increased with age. The HZ 5-year recurrence rate was 4.5%. Average total annual costs of HZ amounted to €11.3 million; the individual costs of an HZ and a PHN HZ episode were €649 and €1,910, respectively. Estimated total costs were split between sick leave (37%), inpatient days (30%), outpatient visits (29%), and outpatient antiviral drugs (4%). In Finland, HZ poses a significant health and economic burden that increases with population aging, highlighting the need to consider HZ prevention.