Camilo J. Acosta

Systematic review of incidence and complications of herpes zoster: towards a global perspective

Objective The objective of this study was to characterise the incidence rates of herpes zoster (HZ), also known as shingles, and risk of complications across the world. Design We systematically reviewed studies examining the incidence rates of HZ, temporal trends of HZ, the risk of complications including postherpetic neuralgia (PHN) and HZ-associated hospitalisation and mortality rates in the general population. The literature search was conducted using PubMed, EMBASE and the WHO library up to December 2013. Results We included 130 studies conducted in 26 countries. The incidence rate of HZ ranged between 3 and 5/1000 person-years in North America, Europe and Asia-Pacific, based on studies using prospective surveillance, electronic medical record data or administrative data with medical record review. A temporal increase in the incidence of HZ was reported in the past several decades across seven countries, often occurring before the introduction of varicella vaccination programmes. The risk of developing PHN varied from 5% to more than 30%, depending on the type of study design, age distribution of study populations and definition. More than 30% of patients with PHN experienced persistent pain for more than 1u2005year. The risk of recurrence of HZ ranged from 1% to 6%, with long-term follow-up studies showing higher risk (5–6%). Hospitalisation rates ranged from 2 to 25/100u2005000 person-years, with higher rates among elderly populations. Conclusions HZ is a significant global health burden that is expected to increase as the population ages. Future research with rigorous methods is important.

Cost-effectiveness of vaccination against herpes zoster and postherpetic neuralgia: a critical review.

OBJECTIVEnThe objective of this study was to systematically review cost-effectiveness studies of vaccination against herpes zoster (HZ) and postherpetic neuralgia (PHN).nnnMETHODSnWe searched MEDLINE and EMBASE databases for eligible studies published prior to November 2013. We extracted information regarding model structure, model input parameters, and study results. We compared the results across studies by projecting the health and economic impacts of vaccinating one million adults over their lifetimes.nnnRESULTSnWe identified 15 cost-effectiveness studies performed in North America and Europe. Results ranged from approximately US

Annual incidence rates of herpes zoster among an immunocompetent population in the United States

10,000 to more than US

Burden of illness, quality of life, and healthcare utilization among patients with herpes zoster in South Korea: a prospective clinical–epidemiological study

100,000 per quality-adjusted life years (QALY) gained. Most studies in Europe concluded that zoster vaccination is likely to be cost-effective. Differences in results among studies are largely due to differing assumptions regarding duration of vaccine protection and a loss in quality of life associated with HZ and to a larger extent, PHN. Moreover, vaccine efficacy against PHN, age at vaccination, and vaccine cost strongly influenced the results in sensitivity analyses.nnnCONCLUSIONnMost studies included in this review shows that vaccination against HZ is likely to be cost-effective. Future research addressing key model parameters and cost-effectiveness studies in other parts of the world are needed.

Predictors of postherpetic neuralgia in patients with herpes zoster: a pooled analysis of prospective cohort studies from North and Latin America and Asia

BackgroundHerpes zoster (HZ), also known as shingles, is a painful and commonly occurring condition in the United States. In spite of a universally recommended vaccine for use in immunocompetent adults aged 60xa0years and older, HZ continues to impact the American public, and a better understanding of its current incidence is needed. The objective of the current study is to estimate the overall and age- and gender-specific incidence rates (IRs) of HZ among an immunocompetent US population in 2011 following availability of a vaccine.MethodsClaims data from the Truven Health MarketScan® Research databases between 01/01/2011 and 12/31/2011 were extracted. Immunocompetent adult patients, enrolled as of January 1, 2011 were analyzed. The denominator was defined as eligible subjects who were immunocompetent, had no evidence of zoster vaccination, and no diagnosis of HZ (International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code 053.xx) in the 90xa0days prior to January 1, 2011. Subjects contributed person-days to the denominator until the occurrence of one of the following events: end of continuous enrollment in the database, a claim for zoster vaccination, diagnosis of HZ or end of the observation period (December 31, 2011). The numerator was defined as enrollees within the denominator file exhibiting evidence of HZ. Annual IRs were calculated for the entire population in the database as well as by gender and age group; standardized IRs were also produced using the 2010 US Census data.ResultsThe overall annual IR of HZ across all ages was 4.47 per 1000 person-years (95xa0% confidence interval [CI]: 4.44–4.50) which monotonically increased with age from 0.86 (95xa0% CI: 0.84–0.88) for those aged ≤19 to 12.78 (95xa0% CI: 12.49–13.07) for patients ≥80xa0years. The IR was 8.46 (95xa0% CI: 8.39–8.52) among adults ≥50xa0years and 10.46 (95xa0% CI: 10.35–10.56) among those aged ≥60xa0years. Women compared to men had higher HZ incidence (5.25, 95xa0% CI: 5.21–5.29 vs. 3.66, 95xa0% CI: 3.62–3.69) and this was seen across all age groups. When adjusted for age and gender using 2010 US Census data, the annual IR was 4.63 per 1000 person-years (95xa0% CI: 4.61–4.66).ConclusionsDespite the availability of a vaccine, HZ remains common among immunocompetent adults in the US with incidence rates of HZ observed to increase with age and be higher in women than men.

Modeling the durability of ZOSTAVAX® vaccine efficacy in people ≥60 years of age.

OBJECTIVESnTo assess the herpes zoster (HZ) disease burden, including the severity and duration of HZ-associated pain, its impact on quality of life (QoL), and healthcare resource utilization (HCRU) in a South Korean clinical setting.nnnMETHODSnPatients aged ≥50 years were followed prospectively for ≤6 months. Based on the duration of their episode at enrollment, cases were classified as incident (<7 days) or prevalent (≥7 days). HZ pain and discomfort were measured with the HZ Severity of Illness (HZ-SOI) severity-by-duration composite score.nnnRESULTSnOne hundred fifty-one patients (69.5% prevalent cases) were enrolled. Prodrome pain was experienced by 68.2% of patients, of whom 95.1% experienced moderate-to-severe pain; post-herpetic neuralgia was experienced by 38.4%. Prevalent disease, higher acute pain, and older age were significant predictors of greater HZ-SOI, while use of antivirals was associated with decreased HZ-SOI. HZ-associated pain was associated with reduced QoL and affected all daily living activities (particularly mood, life enjoyment, general activities, and sleep), resulting in significant HCRU, including primary care doctor, specialist, or physiotherapist consultations, hospitalizations, and emergency department visits.nnnCONCLUSIONnSevere morbidity, impaired QoL, and significant HCRU are associated with HZ in South Korea, especially in older patients, supporting the need for early intervention and preventive strategies to reduce the HZ-associated disease burden.

Herpes zoster-associated severity and duration of pain, health-related quality of life, and healthcare utilization in Taiwan: a prospective observational study.

OBJECTIVESnThe most common complication of herpes zoster (HZ) is postherpetic neuralgia (PHN), a persistent pain that can substantially affect quality of life (QoL). This analysis aimed to evaluate predictors of PHN in HZ patients.nnnMETHODSnA pooled analysis of prospective cohort studies of HZ patients aged ≥ 50 years from North America (Canada), Latin America (Brazil, Mexico, and Argentina), and Asia (Taiwan, South Korea, and Thailand) was performed. Patients within 14 days of rash onset were included. The incidence of PHN was defined as a worst pain score of ≥ 3, persisting/appearing at >90 days after rash onset. Socio-demographics, HZ disease characteristics, treatment, pain-related interference with activities of daily living, and health-related QoL were assessed.nnnRESULTSnOf 702 patients with HZ, 148 (21.1%) developed PHN. Similar risks of PHN were observed across geographic regions. On multivariate analysis, older age, greater severity of pain at rash onset, employment status, walking problems at enrollment, and pain interference affecting social relationships were significantly associated with the development of PHN.nnnCONCLUSIONSnIn addition to older age and severe acute pain, this study suggests that impaired physical and social functioning from acute zoster pain may play a role in the development of PHN in this prospective cohort study of HZ patients from North and Latin America and Asia.

Public Health Impact and Cost-Effectiveness of Hepatitis A Vaccination in the United States: A Disease Transmission Dynamic Modeling Approach

Since 2006, the vaccine, ZOSTAVAX(®), has been licensed to prevent herpes zoster. Only limited clinical follow-up data are available to evaluate duration of protection, an important consideration when developing HZ vaccination policy recommendations. Four Poisson regression models were developed based on an integrated analysis of data from the Shingles Prevention Study and its Short Term Persistence extension to estimate the effects of years-since-vaccination and chronological-age on vaccine efficacy among people ≥60 years old. The models included number of HZ cases parsed into categories by chronological-age and time-since-vaccination as the dependent variable with different explanatory variables in each model. In all models, the interaction between vaccine-group and chronological-age was statistically significant indicating that vaccine efficacy decreases with the expected effects of advancing age but the interaction between vaccine-group and time-since-vaccination was not statistically significant indicating that much of the reduction in vaccine efficacy over time-since-vaccination can be explained by increasing age.

Herpes Zoster-Attributable Resource Utilization and Cost Burden in Patients With Solid Organ Transplant

To assess the severity and duration of herpes zoster (HZ)‐associated pain (ZAP) and its impact on quality of life (QoL) and healthcare utilization (HCRU) from a patient perspective in routine care in Taiwan.

Herpes Zoster Vaccine Coverage in Older Adults in the U.S., 2007–2013

OBJECTIVEnTo assess the population-level impact and cost-effectiveness of hepatitis A vaccination programs in the United States.nnnMETHODSnWe developed an age-structured population model of hepatitis A transmission dynamics to evaluate two policies of administering a two-dose hepatitis A vaccine to children aged 12 to 18 months: 1) universal routine vaccination as recommended by the Advisory Committee on Immunization Practices in 2006 and 2) Advisory Committee on Immunization Practicess previous regional policy of routine vaccination of children living in states with high hepatitis A incidence. Inputs were obtained from the published literature, public sources, and clinical trial data. The model was fitted to hepatitis A seroprevalence (National Health and Nutrition Examination Survey II and III) and reported incidence from the National Notifiable Diseases Surveillance System (1980-1995). We used a societal perspective and projected costs (in 2013 US