The temporal impact of aging on the burden of herpes zoster

Incidence and costs of herpes zoster and postherpetic neuralgia in German adults aged ≥50 years: A prospective study

OBJECTIVES

Herpes zoster (HZ) mainly affects elderly people and immunocompromised individuals. HZ is usually characterized by a unilateral painful skin rash. Its most common complication, postherpetic neuralgia (PHN), may cause chronic debilitating pain. This study aimed to estimate the HZ incidence in individuals aged ≥50 years in Germany, the proportion of PHN and the economic burden.

METHODS

From 2010 to 2014, HZ patients were recruited when consulting physicians in physician networks covering about 157,000 persons aged ≥50 years. PHN was defined as "worst pain" rated ≥3 on the zoster brief pain inventory persisting or appearing over 90 days after rash onset. Costs were calculated based on medical resource utilization and lost working time.

RESULTS

HZ incidence was estimated as 6.7/1000 person-years, increasing with age to 9.4/1000 in ≥80 year-olds. Among 513 HZ patients enrolled, the proportion of PHN was 11.9%, rising with age to 14.3% in HZ patients ≥80 years. Estimated total cost per HZ patient was €156 from the healthcare system perspective and €311 from the societal perspective.

CONCLUSIONS

The study confirmed previous findings that HZ causes a substantial clinical and economic burden in older German adults. It also confirmed the age-related increasing risk of HZ and PHN.

Assessment of the potential public health impact of Herpes Zoster vaccination in Germany

The aim of this study was to compare the public health impact of introducing 2 Herpes Zoster (HZ) vaccines, Zoster Vaccine Live (ZVL) versus a non-live adjuvanted subunit candidate vaccine (HZ/su), in the German population aged 50+ years split into 3 age cohorts, i.e. 50–59, 60–69 and 70+ years, respectively. A multi-cohort static Markov model was developed following age cohorts over their lifetime. Demographic data were obtained from the German federal statistical office. HZ incidence and the proportion of HZ individuals developing post-herpetic neuralgia (PHN) were derived from German specific sources. Age-specific vaccine efficacy and waning rates were based on published clinical trial data. Vaccine coverage for both vaccines was assumed to be 40%, with compliance of the second dose of the HZ/su vaccine of 70%. Sensitivity analyses were performed to assess the robustness of the results. It was estimated that, over the remaining lifetime since vaccination, the HZ/su vaccine would reduce the number of HZ cases by 725,233, 533,162 and 486,794 in the 3 age cohorts, respectively, compared with 198,477, 196,000 and 104,640, using ZVL. The number needed to vaccinate (NNV) to prevent one HZ case ranged from 8 to 11 using the HZ/su vaccine compared with 20 to 50 using ZVL. Corresponding NNV to prevent one PHN case ranged from 39 to 53 using the HZ/su vaccine compared with 94 to 198 using ZVL. Due to the higher, sustained vaccine efficacy, the candidate HZ/su vaccine demonstrated superior public health impact compared with ZVL.