A systematic review and meta-analysis of risk factors for postherpetic neuralgia

Public health impact model estimating the impact of introducing an adjuvanted recombinant zoster vaccine into the UK universal mass vaccination programme

OBJECTIVES

In 2013, the herpes zoster (HZ) immunisation programme was introduced in the UK, recommending vaccination of adults 70 years of age (YOA) with the zoster vaccine live (ZVL), the only vaccine available at the time. The recently approved adjuvanted recombinant zoster vaccine (RZV) has a substantially different clinical profile that may offer additional benefits.This study aimed to 1) assess the public health impact (PHI) of introducing RZV in the UK compared with the current vaccination strategy and 2) explore via scenario analyses the optimal age group of vaccination in terms of PHI.

DESIGN

A previously developed health economic model was adapted to the UK setting.

SETTING

Calculations were based on efficacy data from pivotal clinical trials, HZ incidence and postherpetic neuralgia (PHN) probability from a UK study and HZ-associated complication rates from published literature.

POPULATION

The base-case population considered a 2018-projected UK vaccination cohort of individuals 70 YOA.

INTERVENTIONS

Vaccination with ZVL or RZV, assuming a first-dose coverage of 48.3% for both vaccines and 70% compliance for the second dose of RZV.

OUTCOME MEASURES

Outcomes included reduction of HZ and PHN cases, complications and the use of healthcare resources over a life-time horizon. The impact of coverage and second-dose compliance was also explored.

RESULTS

Compared with no vaccination, RZV would lead to a reduction of 30 262 HZ and 5409 PHN cases while ZVL would lead to a reduction of 7909 HZ and 3567 PHN cases. The number needed to vaccinate to prevent 1 HZ case is 12 with RZV and 45 with ZVL. The highest PHI with RZV could be achieved in individuals 60 or 65 YOA.

CONCLUSION

Under the model assumptions, RZV is predicted to avert more HZ and PHN cases compared with ZVL. Results were robust under different scenario and sensitivity analyses.

CT-Guided Stellate Ganglion Pulsed Radiofrequency Stimulation for Facial and Upper Limb Postherpetic Neuralgia

Objective: Postherpetic neuralgia (PHN) is the most common complication of herpes zoster, manifesting as a persistent, spontaneous, knife-like pain or paroxysmal burning that seriously affects a patient’s quality of life. An effective treatment of PHN is lacking. This retrospective study examined the efficacy and safety of stellate ganglion (SG) pulsed radiofrequency (PRF) on facial and upper limb PHN.

Methods: Eighty-four patients with PHN on the face or upper limbs were enrolled for the study. Patients were randomly divided into two surgical groups according to the order of enrollment; one group underwent SG block (SG-B group, n = 42) and the other underwent SG pulsed radiofrequency (SG-P group, n = 42). After surgery, patients were followed at 1 week, 2 weeks, 1 month, 3 months, and 6 months. Observation at each follow-up included basic patient characteristics, visual analog scale (VAS), quality of life (QOL) using Physical Component Summary (PCS), and Mental Component Summary (MCS) to assess, total effective rate, complications and side effects.

Results: Compared with preoperative values, VAS decreased in both groups after surgery (P < 0.05). In the SG-B group, VAS increased after 1 month, while in the SG-P group, VAS gradually decreased at later follow-up time points. VAS decreased more significantly in the SG-P group after 1 month (P < 0.05). PCS and MCS increased in both groups after the operation, and the difference was significant compared with preoperative values (P < 0.05). The total effective rates of the SG-B and SG-P groups were 64.3 and 83.3%, respectively. The total effective rate of the SG-P group was higher than that of the SG-B group (P < 0.05). The incidence of complications and side effects in the SG-B group was higher than that in the SG-P group (P < 0.05).

Conclusion: SG pulsed radiofrequency treatment of facial and upper limb PHN is safe and effective. It is a treatment method worth promoting.

Response to Transforaminal Epidural Block as a Useful Predictive Factor of Postherpetic Neuralgia

Despite the high frequency of nerve blocks in the acute phase of herpes zoster, factors associated with intervention, such as response to epidural block, have not been analyzed as predictive factors of postherpetic neuralgia (PHN). To determine the predictive factors of progression to PHN in the presence of interventions, we analyzed the medical records of 145 patients who underwent transforaminal epidural injection (TFEI) in the acute phase of herpes zoster. A total volume of 5 mL (a mixture of 0.5% lidocaine and 5 mg dexamethasone) was injected during TFEI. Corticosteroid was used only for the first TFEI. Clinical data of age, sex, involved dermatome, presence of comorbidity, time from zoster onset to first TFEI, numerical rating scale (NRS) before TFEI, NRS at 1 week and 1, 3, and 6 months after the first TFEI, and number of TFEI were collected and analyzed. Through multivariate logistic regression analysis, pain improvement less than 50% at 1 week after the first TFEI was a strong predictive factor of progression of PHN at all time points. Response to TFEI appears to be a stronger predictive factor of progression to PHN than patient factors of sex, age, degree of initial pain, and presence of co-morbidity.

Pain Clinic in Tibet, China: A Single-Center Retrospective Study

Pain disease is a worldwide problem.The prevalence of chronic pain in developed and developing countries has been reported in some published research. However, little knowledge of situation of pain clinic in Tibet is known. Tibet Autonomous Region People's Hospital established the first pain clinic in Tibet. This study collected and analyzed the data of medical records of pain clinic in Tibet Autonomous Region People's Hospital from September 2017 to August 2018. The results showed that the total amounts of patients visiting pain clinic were very small, the most common pain diseases were postherpetic neuralgia and sciatica, and more female patients visited the pain clinic than male patients. All these results indicate that the hospital and government need to pay more attention to the development and promotion of pain medicine in Tibet to make Tibetans being accessed to high-quality pain clinic service.

Recurrence Rate of Herpes Zoster and Its Risk Factors: a Population-based Cohort Study

BACKGROUND

Herpes zoster (HZ) is generally thought to occur once in a lifetime and recurrence is considered to be limited to immunocompromised individuals. Although HZ recurrence rates seem to be increasing, there have been few studies exploring these rates in the general population. We investigated the recurrence rate and associated risk factors in the general population.

METHODS

We used the population-based samples of the National Health Insurance Service database to identify cases of initial HZ episodes from January 1, 2002 to December 31, 2013. We also followed up on these cases through December 31, 2013 to identify recurrence.

RESULTS

Overall, the incidence rate of HZ is 5.1 per 1,000 person years and the recurrence rate is 12.0 per 1,000 person years. There were 2,100 recurrent cases out of 39,441 initial episodes with 4.4 years of the mean follow-up period. We identified significant risk factors for recurrence such as old age (51-70 years) (hazard ratio [HR], 1.447; 95% confidence interval [CI], 1.311-1.598), women (1.476; 1.345-1.619), zoster-related pain (ZRP) longer than 30 days (cases of ZRP lasting 31-90 days [1.200; 1.042-1.383], and ZRP lasting longer than 90 days [2.293; 1.990-2.643]). Concurrent hematologic malignancies (2.864; 1.929-4.251), autoimmune diseases (1.466; 1.252-1.715), dyslipidemia (1.390; 1.263-1.530), and hypertension (1.222; 1.107-1.350) were also significant risk factors.

CONCLUSION

Our results suggest that the recurrence of HZ is much more common than generally expected, and that the associated risk factors can play an important role in predicting recurrence.

The Effect of Interventional Pain Management on Treating Postherpetic Neuralgia

Background:

Herpes zoster (HZ) is identified to induce postherpetic neuralgia (PHN) which is difficult to cure. PHN-related pain brings patients not only physical discomfort but also mental depression and anxiety. Currently, the main purpose of PHN treatment is to reduce patients’ pain. Now treatment combining some international pain management and drug therapy has come up.

Aims and Objective:

This study aims to evaluate the effect of interventional management through meta-analysis.

Materials and Methods:

Interventional pain management was defined as a direct strategy on nerve through physical or chemical method. Drug therapy was always regarded as control. Potentially relevant articles were searched in PubMed, EMBASE, and the Cochrane Library through key words by consensus. Pain severity was evaluated by a validated visual analog scale (VAS). Moreover, the weighted mean difference was used to calculate pain intensity. Some trails recorded the efficiency rate and odds ratio was used to calculate the effectiveness. Statistical heterogeneity was measured by the value of I², and when statistical I² > 50%, subgroup analysis was used to seek for the source of heterogeneity.

Results:

Pulsed radiofrequency (PRF) combined with medication reduced the VAS scores at 1, 2, 4, and 8 weeks after treatment. The nerve block combined with medication reduced VAS scores at 8 weeks after treatment, but there is no difference between the results of medication alone at 1, 2, and 4 weeks after treatment.

Conclusion:

The interventional mean of PRF combined with medication has a good effect on PHN. The effect of nerve block combined with medication on PHN seems to be the same as that of medication alone. Besides, a long period with high-quality randomized controlled trial should be done to verify the results.

AAPT Diagnostic Criteria for Peripheral Neuropathic Pain: Focal and Segmental Disorders

Peripheral neuropathic pain is among the most prevalent types of neuropathic pain. No comprehensive peripheral neuropathic pain classification system that incorporates contemporary clinical, diagnostic, biological, and psychological information exists. To address this need, this article covers the taxonomy for 4 focal or segmental peripheral neuropathic pain disorders, as part of the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership and the American Pain Society (APS) collaborative to develop a standardized, evidence-based taxonomy initiative: the ACTTION-APS Pain Taxonomy (AAPT). The disorders-postherpetic neuralgia, persistent posttraumatic neuropathic pain, complex regional pain disorder, and trigeminal neuralgia-were selected because of their clinical and clinical research relevance. The multidimensional features of the taxonomy are suitable for clinical trials and can also facilitate hypothesis-driven case-control and cohort epidemiologic studies. PERSPECTIVE: The AAPT peripheral neuropathic pain taxonomy subdivides the peripheral neuropathic pain disorders into those that are generalized and symmetric and those that are focal or segmental and asymmetric. In this article, we cover the focal and segmental disorders: postherpetic neuralgia, persistent posttraumatic neuropathic pain, complex regional pain disorder, and trigeminal neuralgia. The taxonomy is evidence-based and multidimensional, with the following dimensions: 1) core diagnostic criteria; 2) common features; 3) common medical and psychiatric comorbidities; 4) neurobiological, psychosocial, and functional consequences; and 5) putative neurobiological and psychosocial mechanisms, risk factors, and protective factors.

Quantifying drivers of antibiotic resistance in humans: a systematic review

Mitigating the risks of antibiotic resistance requires a horizon scan linking the quality with the quantity of data reported on drivers of antibiotic resistance in humans, arising from the human, animal, and environmental reservoirs. We did a systematic review using a One Health approach to survey the key drivers of antibiotic resistance in humans. Two sets of reviewers selected 565 studies from a total of 2819 titles and abstracts identified in Embase, MEDLINE, and Scopus (2005-18), and the European Centre for Disease Prevention and Control, the US Centers for Disease Control and Prevention, and WHO (One Health data). Study quality was assessed in accordance with Cochrane recommendations. Previous antibiotic exposure, underlying disease, and invasive procedures were the risk factors with most supporting evidence identified from the 88 risk factors retrieved. The odds ratios of antibiotic resistance were primarily reported to be between 2 and 4 for these risk factors when compared with their respective controls or baseline risk groups. Food-related transmission from the animal reservoir and water-related transmission from the environmental reservoir were frequently quantified. Uniformly quantifying relationships between risk factors will help researchers to better understand the process by which antibiotic resistance arises in human infections.

Rethinking the causes of pain in herpes zoster and postherpetic neuralgia: the ectopic pacemaker hypothesis

INTRODUCTION

Pain in herpes zoster (HZ) and postherpetic neuralgia (PHN) is traditionally explained in terms of 2 processes: irritable nociceptors in the rash-inflamed skin and, later, deafferentation due to destruction of sensory neurons in one virally infected dorsal root ganglion.

OBJECTIVES AND METHODS

Consideration of the evidence supporting this explanation in light of contemporary understanding of the pain system finds it wanting. An alternative hypothesis is proposed as a replacement.

RESULTS

This model, the ectopic pacemaker hypothesis of HZ and PHN, proposes that pain in both conditions is driven by hyperexcitable ectopic pacemaker sites at various locations in primary sensory neurons affected by the causative varicella zoster virus infection. This peripheral input is exacerbated by central sensitization induced and maintained by the ectopic activity.

CONCLUSIONS

The shift in perspective regarding the pain mechanism in HZ/PHN has specific implications for clinical management.

Herpes Zoster

Primary care providers and hospitalists frequently encounter older or immunocompromised patients with herpes zoster accompanied by debilitating pain. Atypical presentations and zosteriform herpes simplex may present diagnostic challenges to clinicians. This article summarizes the background, evidence, and guidelines for the diagnosis, complications, treatment, and prevention of herpes zoster. Diagnosis of challenging cases relies on polymerase chain reaction as the preferred test. Treatment focuses on optimal use of antiviral therapy and analgesics. Prevention emphasizes utilization of a new recombinant zoster vaccine, which reduces the incidence of herpes zoster by more than 90% and is preferred to the live attenuated herpes zoster vaccine.

Effect of 2% lidocaine continuous epidural infusion for thoracic or lumbar herpes-zoster-related pain

Few treatments are effective to manage herpes-zoster (HZ)-related pain. This retrospective study focused on the efficacy of 2% lidocaine continuous epidural infusion on pain control and quality of life in patients with thoracic or lumbar HZ.A total of 256 patients with thoracic or lumbar HZ were reviewed for this study. Patients included in the study were divided into continuous epidural infusion (70 mL 2% lidocaine + 180 mL 0.9% normal saline) and medical therapy group (group1) and only medical therapy group (group2). European Organization for Research and Treatment of Cancer and Izbicki pain score were used to evaluate the pain control and quality of life before therapy, and 6 and 9 months after therapy.For 256 patients with HZ (thoracic HZ = 162, lumbar HZ = 94), 53.1% was women. Mean ± standard deviation age was 69.4 ± 9.5 ( range, 38-85) years. Significant differences between the 2 groups in terms of quality of life and pain control were detected after 6 and 9 months follow-up (P < .001). For patients with HZ at 1 to 3 months after rash onset, the pain score was significantly lower in group 1 (P < .001). Sixteen patients with postherpetic neuralgia (PHN) underwent continuous epidural infusion therapy. Only 4 patients achieved satisfactory pain relief. Seven patients required analgesic drugs, and 6 patients still were unable to work, 10/16 (62.5%) patients had readmission. In addition, the pain score was higher in patients with HZ with diabetes (P < .001). Epidural infection occurred in 6 patients (8.8%), catheter dislodgement in 4 patients (5.8%), and catheter leakage in 3 patients (4.4%). There was no spinal epidural abscesses occurred.2% lidocaine continuous epidural infusion therapy can lead to sustained pain relief and improve the quality of life in patients with for thoracic or lumbar HZ at 1 to 3 months after rash onset. Epidural lidocaine is avoided for the treatment PHN, and the level of glucose might be associated with zoster-related pain.

Acupuncture for postherpetic neuralgia: Systematic review and meta-analysis

BACKGROUND

Acupuncture is widely used for postherpetic neuralgia (PHN) in China but its effect is unclear. We aim to evaluate the effect and safety of acupuncture for PHN.

METHODS

The Cochrane Skin Group Trials Register, The Cochrane Central Register of Controlled Trials, MEDLINE, Embase, the Chinese Biomedical Literature Database, the China National Knowledge Infrastructure, and the gray literature were searched. Randomized controlled trials (RCTs) comparing acupuncture alone versus no treatment/another active therapy/sham acupuncture, or comparing acupuncture with another active therapy versus the same active therapy were included.

RESULTS

Seven RCTs comparing acupuncture versus pharmacologic therapy were included. Meta-analysis was conducted for acupuncture's effect on PHN evaluating by pain intensity. Results from 2 RCTs showed that compared with pharmacologic therapy, acupuncture was better in decreasing the pain intensity measured by visual analog scale score (mean difference: 1.80, 95% confidence interval 1.72-1.87; P < .001). The limitations of the study are as follows: only trials comparing acupuncture versus pharmacologic therapy were included and all of the included trials were performed in China.

CONCLUSION

There was not enough evidence to suggest that acupuncture was superior to pharmacologic therapy in improving global impression or life quality. No adverse effects about acupuncture were reported. In all, acupuncture is safe and might be effective in pain relieving for patients with PHN. Given the low quality of included studies, the results are not conclusive and more large-scale RCTs with high quality are needed.

Burden of herpes zoster in 16 selected immunocompromised populations in England: a cohort study in the Clinical Practice Research Datalink 2000-2012

OBJECTIVES

Herpes zoster (HZ) is caused by reactivation of varicella-zoster virus which remains latent in individuals after a varicella infection. It is expected that HZ will be more frequent in immunocompromised (IC) individuals than in immunocompetent (IC-free). This study assessed the incidence rate (IR) of HZ in individuals with a wide set of IC conditions and in IC-free individuals.

SETTING

A retrospective cohort study was conducted in England using data (January 2000 to March 2012) from the Clinical Practice Research Datalink with linkage to the Hospital Episodes Statistics.

PARTICIPANTS

A cohort of 621 588 individuals with 16 selected IC conditions and a gender/age-matched cohort of IC-free individuals were identified. The IC conditions included haematopoietic stem cell transplant (HSCT), solid organ transplant, malignancies, autoimmune diseases and users of immunosuppressive medications.

OUTCOMES

IR of HZ per 1000 person-years (PY) was estimated. Proportions of postherpetic neuralgia (PHN) and other HZ complications within 90 days of HZ onset were also estimated among patients with HZ. Risk factors for PHN in IC individuals with HZ were assessed by a multivariate regression model.

RESULTS

The overall IR of HZ in the IC cohort was 7.8/1000 PY (95% CI 7.7 to 7.9), increasing with age from 3.5/1000 PY (3.4-3.7) in individuals aged 18-49 years to 12.6/1000 PY (12.2-13.0) in individuals aged ≥80 years. This IR in the IC-free cohort was 6.2/1000 PY (6.1-6.3). The overall IR of HZ varied across IC conditions, ranging from 5.3 (5.1-5.5) in psoriasis to 41.7/1000 PY (35.7-48.4) in HSCT. The proportions of PHN and other HZ complications were 10.7% (10.2-11.1) and 2.9% (2.7-3.2) in the IC cohort, but 9.1% (8.7-9.5) and 2.3% (2.1-2.6) in the IC-free cohort, respectively.

CONCLUSION

IC population contributes to the public health burden of HZ in England. Vaccination might be the most preferable HZ preventive measure for the IC population.

Effectiveness of herpes zoster vaccination in an older United Kingdom population

BACKGROUND

Vaccination against herpes zoster was introduced in the United Kingdom in 2013 for individuals aged 70 years, with a phased catch-up campaign for 71-79 year olds. Vaccine introduction has resulted in a marked fall in incident herpes zoster and in post-herpetic neuralgia (PHN), but formal evaluation of vaccine effectiveness is needed.

METHODS

In a population-based cohort study of older individuals born between 1933 and 1946, we used linked UK anonymised primary care health records for the first three years of the vaccination programme (01/09/2013-31/08/2016) and multivariable Poisson regression to obtain incidence rates and vaccine effectiveness (VE) against zoster and PHN.

RESULTS

Among 516,547 individuals, 21% were vaccinated. Incidence of zoster was 3.15/1000 person-years in vaccinees and 8.80/1000 person-years in unvaccinated individuals. After adjustment, VE was 64% (95%CI = 60-68%) against incident zoster and 81% (95%CI = 61-91%) against PHN, with very similar VE estimates in the routine and catch-up cohorts. VE against zoster was lower in those with a previous history of zoster: 47% (95%CI = 31-58%) versus 64% (95%CI = 60-68%) in those without previous zoster. There was evidence of waning VE over time, from 69% (95%CI = 65-74%) in the first year after vaccination to 45% (95%CI = 29-57%) by the third year.

CONCLUSION

This first formal assessment of VE in the UK zoster vaccination programme demonstrates good effectiveness of zoster vaccine, and very good protection against PHN. The findings provide evidence that VE is similar across the age groups targeted for vaccination in the UK, and on duration of protection of the vaccine in public health use. The study provides key information for decision-makers about the future direction of UK zoster vaccination programme, indicating that the live zoster vaccine may be more cost-effective than estimated previously. It also supports efforts to communicate the benefits of zoster vaccination to address the declining coverage observed across the UK.

Activated Glia Increased the Level of Proinflammatory Cytokines in a Resiniferatoxin-Induced Neuropathic Pain Rat Model

BACKGROUND AND OBJECTIVES

Administration of resiniferatoxin (RTX) can mimic the clinical symptoms of postherpetic neuralgia. However, it is unclear whether activated glia contribute to the pathogenesis of RTX-induced neuropathic pain; furthermore, the relationship between p38, N-methyl-D-aspartate receptor type 2B (NR2B) as well as proinflammatory cytokines and activated glia remains unknown.

METHODS

Intraperitoneal injection of RTX was performed to induce neuropathic pain in rats. Mechanical allodynia and thermal hyperalgesia were assessed by von Frey filaments and a radiant heat stimulus, respectively. Western blot and immunofluorescence labeling examined the expression of NR2B, activated glia markers, p38, and proinflammatory cytokines in the spinal cord. We further investigated the effect of the glial inhibitors, fluorocitrate and minocycline, on nociceptive behaviors and expression of p38, NR2B, and proinflammatory cytokines.

RESULTS

Resiniferatoxin leads to an increase of paw withdrawal latency to a heat stimulus and caused a mechanical allodynia within 2 weeks. The expression of tumor necrosis factor α, IL-1β, p38, and NR2B was up-regulated in RTX-induced neuropathic pain rat model and lasted for at least 49 days. Microglia were activated at the early phase of the disease, whereas activated astrocytes were detected in the sustainment phase. Both minocycline and fluorocitrate attenuated the nociceptive behaviors and expression of related proteins.

CONCLUSIONS

Activated glia participate in the pathogenesis of RTX-induced neuropathic pain and are likely to be the source of proinflammatory cytokines. Inhibition of glia contributes to an analgesic effect. These findings provide a novel strategy for the treatment of postherpetic neuralgia.

Epidemiology and long-term disease burden of herpes zoster and postherpetic neuralgia in Taiwan: a population-based, propensity score-matched cohort study

Background

The objectives of this study were to characterize the burden of herpes zoster, as well as the longitudinal and incremental changes of healthcare service utilization among individuals with herpes zoster and postherpetic neuralgia (PHN) compared to those without.

Methods

Using the National Health Insurance Research Database (NHIRD), we established a herpes zoster cohort of people diagnosed with herpes zoster between 2004 and 2008 as study cases. Another subset of the NHIRD, which was randomly selected from all elderly beneficiaries between 2004 and 2008 served as a non-herpes-zoster elderly control pool. Each case was then assigned one matched control according to age, gender, index date and propensity score. PHN cases were defined as those with persisting pain for more than 90 days after the onset of herpes zoster.

Results

Between 2004 and 2008, about 0.6 million patients were newly diagnosed with herpes zoster. The incidence increased with age, and most cases were identified during the summer period. Herpes zoster cases were found to have higher consumption of all types of healthcare services in the first year after the index date. Such increases were particularly obvious for patients with PHN, who showed incremental increases on average of 16.3 outpatient visits, 0.4 emergency room visits and 0.24 inpatient admissions per year.

Conclusions

The incidence of herpes zoster increased with age and changed according to the seasons. Patients with herpes zoster were associated with higher healthcare utilization and this increase in healthcare utilization was most obvious for herpes zoster patients with PHN.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5247-6) contains supplementary material, which is available to authorized users.

Clinical efficacy of transforaminal epidural injection for management of zoster-associated pain: a retrospective analysis

OBJECTIVES

Transforaminal epidural injection (TFEI) has superior accessibility to the dorsal root ganglion, which is an essential location of pain signaling in herpes zoster. However, the effectiveness of TFEI for herpes zoster patients has not previously been studied. We retrospectively analyzed the efficacy of TFEI for pain control and prevention of PHN in patients with acute and subacute herpes zoster.

METHODS

Medical records of 137 patients who underwent TFEI for zoster-associated pain (ZAP) were reviewed. The participants were divided into two groups: acute TFEI group (TFEI within 30 days after zoster) and subacute TEEI group (TFEI between 30 and 90 days). The efficacy of TFEI was assessed by a numerical rating scale (NRS), doses of medications, and time to relief of ZAP. Incidence of PHN at 1 week to 6 months after TFEI was evaluated.

RESULTS

Time to ZAP relief was significantly shorter and the incidence of PHN was significantly lower in the acute TFEI group than in the subacute TFEI group. Rate of medication discontinuation was significantly higher in the acute TFEI group than in the subacute TFEI group.

CONCLUSIONS

Early application of TFEI in the acute phase of zoster can be a useful option for ZAP control and prevention of chronic neuropathic pain such as PHN.

Letter to the editor regarding "The role of age-sex interaction in the development of post-herpetic neuralgia"

The objective of the study was to evaluate the role of age and sex and their combined effect in the development of post-herpetic neuralgia (PHN) in a large population-based study, in order to confirm the results published previously by Amicizia et al. Data were extracted from population and healthcare databases from the Valencia Region (2009-2014). Logistic regressions were implemented to estimate the effect of increasing age on the probability of developing PHN stratified by sex. From a cohort of 2,289,485 subjects ≥ 50 years, 87,086 cases of HZ were registered and 13,658 (15.7%) of them developed PHN. In our population, PHN cases were more common in women and rose with increasing age independently of the sex.

Studies with herpes zoster vaccines in immune compromised patients

INTRODUCTION

The active component of the herpes zoster vaccine (ZVL), licensed for people ≥50 years of age, is a live attenuated varicella-zoster virus. ZVL is contraindicated for immune compromised individuals, with limited regard to the degree of immunosuppression. Areas covered: This review evaluates phase I and II and observational studies for ZVL, and published reports of the off-label use of ZVL, for conditions and therapies for which investigators considered the risk-benefit for using ZVL to be favorable. It also discusses exploratory trials of ZVL for additional immune compromising conditions, and summarizes clinical guidelines from many countries and professional societies that are based upon recent investigations. Studies in immune compromised patients of investigational vaccines that do not contain live virus are reviewed. Expert commentary: It is likely that past and ongoing research with ZVL will define immune compromising diseases and/or therapies for which the risk-benefit for using ZVL vaccine is favorable. The main variables to consider in this assessment in immune compromised patients are safety, immunogenicity, protection against herpes zoster, and persistence of protection. Vaccination against herpes zoster prior to suppressing immunity is an important clinical strategy, although efficacy of this approach has not been evaluated in a clinical trial.

Post-herpetic neuralgia - a review of current management and future directions

Post-herpetic neuralgia (PHN) is common and treatment is often suboptimal with less than half of patients achieving adequate 50% pain relief. As an area of unmet clinical need and as an archetype of neuropathic pain, it deserves the attention of clinicians and researchers. Areas covered: This review summarises the epidemiology, pathophysiology, risk factors and clinical features of varicella infection. It describes the current and possible future management strategies for preventing varicella infection and reactivation and for treating PHN. Expert opinion: A highly successful Varicella Zoster (VZV) vaccine has not been universally adopted due to fears that it may increase Herpes Zoster (HZ) incidence - and thus PHN - in older, unvaccinated generations. This is a controversial theory but advances in the efficacy of vaccines against HZ may allay these fears and encourage more widespread adoption of the VZV vaccine. Treatment of PHN, as for any neuropathic pain, must be multidisciplinary and multimodal. Advances in sensory phenotyping technology and genomics may allow more individualised treatment. Traditional research methodologies are ill-suited to assess the kind of complex interventions that are necessary to achieve better clinical outcomes in this challenging field.

The role of age-sex interaction in the development of post-herpetic neuralgia

Post-herpetic neuralgia is the most frequent complication of herpes zoster and affects up to 30% of patients. Increased age is a well-recognized risk factor, while the role of gender is highly uncertain. Little research has been performed into a possible combined effect of age and sex in post-herpetic neuralgia.

The objective of the study was to study the role of age and sex and their combined effect in the development of post-herpetic neuralgia.

This retrospective study enrolled adult subjects with at least one episode of herpes zoster in the previous 10 y. A questionnaire on the patient's socio-demographic, anamnestic and clinical characteristics was administered by general practitioners. Multivariable logistic regression was used to detect relationships between post-herpetic neuralgia and age, sex and their interaction.

Fifty-nine of 272 patients reported post-herpetic neuralgia: a prevalence of 21.7%. Subjects with post-herpetic neuralgia (mean age 70.9 years) were significantly older (P = .001) than those without (64.2 years), the standardised mean difference being 0.5; no significant between-sex association was revealed (P = .96). A fully adjusted multivariable logistic analysis, however, revealed a highly significant (P = .007) age-sex interaction, with an odds ratio of 0.92; this also showed that older males were more likely to report post-herpetic neuralgia than younger males, while no obvious age-associated pattern was observed among females.

We discerned a significant age-by-sex interaction in the development of post-herpetic neuralgia, which suggests that the effect of age on the development of this condition may differ between men and women.

Comparison of efficacy of continuous epidural block and pulsed radiofrequency to the dorsal root ganglion for management of pain persisting beyond the acute phase of herpes zoster

Background

There is little evidence regarding the effectiveness of intervention methods in the treatment of zoster-related pain (ZAP) after the acute phase of zoster. Generally, if ZAP remains after more than 180 days from its onset, the likelihood of pain reduction is very low; this condition is considered as a “well established” post-herpetic neuralgia (PHN). Although the clinical efficacy of intrathecal steroid injection and spinal cord stimulation (SCS) for ZAP management has been reported, these interventions are not widely used due to inherent disadvantages. Continuous epidural block is widely used in clinical practice, and the effectiveness of pulsed radiofrequency (PRF) to the dorsal root ganglion (DRG) in the treatment of ZAP already has been reported.

Objectives

The purpose of this study was to compare the clinical efficacy of continuous epidural block and DRG PRF beyond acute phase of zoster, bur before PHN was well established (from 30 days to180 days after zoster onset).

Study design

Retrospective comparative study.

Methods

A total of 42 medical records were analyzed. Patients were divided into two groups according to the type of procedure utilized: continuous epidural block (continuous epidural group) and DRG PRF (PRF group). The clinical efficacy of the procedure was evaluated using a numeric rating scale (NRS) and the medication dose before and 1 to 6 months after the procedure.

Results

There was a significant decrease in the NRS value with time in both groups. However, this decrease was more significant in the PRF group than in the continuous epidural group. The medication doses decreased significantly in the PRF group over time, but not in the continuous epidural group. The rate of clinically meaningful PHN (NRS≥3) was also lower in the PRF group than in the continuous epidural group.

Conclusions

This study revealed that DRG PRF was more effective than a continuous epidural block in treating ZAP after the acute phase of zoster. A neuromodulation method such as DRG PRF may be a useful option for reducing the progression of neuropathic changes caused by the persistent transmission of a pain signal after the acute phase of zoster.

Effect of Repetitive Intracutaneous Injections with Local Anesthetics and Steroids for Acute Thoracic Herpes Zoster and Incidence of Postherpetic Neuralgia

Background

Treatment of established postherpetic neuralgia (PHN) is difficult and often disappointing. In this study, we assessed the efficacy of repetitive intracutaneous injections with local anesthetics and steroids in acute thoracic herpes zoster (HZ) pain, herpetic eruption, and incidence of PHN.

Methods

Ninety-three patients with acute thoracic HZ were randomly assigned to receive a standard treatment of antiviral medication with p.o. analgesics or the standard treatment with the addition of repetitive intracutaneous injections of a local anesthetic and steroid mixture. Patients were permitted to take tramadol when the visual analog scale (VAS) ≥ 4. Pain assessment using VAS was conducted at the initial visit, as well as 1, 2, 4, 12, and 24 weeks after the end of the treatments.

Results

In comparison with the standard treatment group, the VAS scores of the intracutaneous injection group were significantly lower during the study. The intracutaneous injection group also reported shorter duration of pain and skin eruption than the control group ( P  = 0.005 vs P  < 0.001, respectively). At 1 month post-therapy, 12.8% patients in the intracutaneous injection group reported zoster-associated pain, compared with 47.8% in the standard treatment group ( P  < 0.001). At 3 and 6 months post-therapy, the incidence of PHN was still significantly lower in the intracutaneous injection group than the standard treatment group. EuroQol VAS scores were significantly higher in the intracutaneous injection group vs standard treatment group (P < 0.001).

Conclusion

Repetitive intracutaneous injections with local anesthetics and steroids along with standard treatment significantly reduce the duration of pain and herpetic eruption and incidence of PHN.

FV-100 versus valacyclovir for the prevention of post-herpetic neuralgia and the treatment of acute herpes zoster-associated pain: A randomized-controlled trial

This prospective, parallel-group, randomized, double-blind, multicenter study compared the efficacy and safety of FV-100 with valacyclovir for reducing pain associated with acute herpes zoster (HZ). Patients, ≥50 years of age, diagnosed with HZ within 72 h of lesion appearance who had HZ-associated pain, were randomized 1:1:1 to a 7-day course of either FV-100 200 mg QD (n = 117), FV-100 400 mg QD (n = 116), or valacyclovir 1000 mg TID (n =117). Efficacy was evaluated on the basis of the burden of illness (BOI; Zoster Brief Pain Inventory scores); incidence and duration of clinically significant pain (CSP); pain scores; incidence and severity of post-herpetic neuralgia (PHN); and times to full lesion crusting and to lesion healing. Safety was evaluated on the basis of adverse event (AE)/SAE profiles, changes in laboratory and vital signs values, and results of electrocardiograms. The burden of illness scores for pain through 30 days were 114.5, 110.3, and 118.0 for FV-100 200 mg, FV-100 400 mg, and valacyclovir 3000 mg, respectively. The incidences of PHN at 90 days for FV-100 200 mg, FV-100 400 mg, and valacyclovir 3000 mg were 17.8%, 12.4%, and 20.2%, respectively. Adverse event and SAE profiles of the two FV-100 and the valacyclovir groups were similar and no untoward signals or trends were evident. These results demonstrate a potential for FV-100 as an antiviral for the treatment of shingles that could both reduce the pain burden of the acute episode and reduce the incidence of PHN compared with available treatments.

Earlier treatment improves the chances of complete relief from postherpetic neuralgia

Background

As herpes zoster progresses via postherpetic neuralgia (PHN) to well-established PHN, it presents its recalcitrant nature to the treatment. At this point, the well-established PHN is fixed as a non-treatable, but manageable chronic painful neuropathic disorder. This study evaluated the incidence of complete relief from PHN according to PHN duration at their first visit, and the other factors influencing it.

Methods

A retrospective chart review was performed on patients with PHN at a university-based pain clinic over 7 years. The responders were defined as patients who had complete relief from pain after 1 year of active treatment. Age, sex, PHN duration at their first visit, dermatomal distribution, and underlying disorders were compared in the responder and non-responder groups. Responders were also compared according to these factors.

Results

Among 117 PHN patients (M/F = 48/69), 35 patients (29.9%) had complete relief from PHN. Mean ages were 64.3 ± 10.6 and 66.9 ± 10.7 years, numbers of male to female patients were 11/24 and 37/45, and mean durations of PHN at their first visit were 8.5 ± 6.3 and 15.3 ± 10.7 months in the responder and non- responder groups, respectively. In addition, PHN patients who visited the clinic before 9 months showed a better result. Dermatomal distribution and underlying disorders did not show significant differences.

Conclusions

Almost 30% of PHN patients received complete relief. Those who sought treatment in a pain clinic before 9 months received a better result.

A case control study on family history as a risk factor for herpes zoster and associated outcomes, Beijing, China

BACKGROUND

Hospital-based case control studies have found family history of herpes zoster (HZ) was associated with risk of HZ, but the role of family history is not fully examined for other HZ-associated outcomes such as recurrent HZ, occurrence of postherpetic neuralgia (PHN), and HZ with different pain severities.

METHODS

We conducted a population-based matched case control study. HZ cases that occurred during December 1, 2011 to November 30, 2012 were identified by face-to-face interview with all residents of eight selected communities/villages from three districts of Beijing, China. Medical records were reviewed for those who sought healthcare for HZ. For each case-patient, three, age-matched controls (±5 years) without HZ were enrolled from the same community/village of the matched case. Data on family history of HZ were collected by interview and only defined among first-degree relatives.

RESULTS

A total of 227 case-patients and 678 matched controls were enrolled. Case-patients were more likely to report a family history of HZ [odds ratio (OR) =2.4, P = 0.002]. Compared with controls, association of family history decreased from HZ with PHN to HZ without PHN (OR = 6.0 and 2.3, respectively; P = 0.002 for trend), from recurrent HZ to primary HZ (OR = 9.4 and 2.2, respectively; P = 0.005 for trend), and from HZ with moderate or severe pain to HZ with mild or no pain (OR = 3.2 and 0.8, respectively; P < 0.001 for trend).

CONCLUSIONS

Family history of HZ was associated with HZ occurrence and was more likely in HZ case-patients with PHN, recurrences, and painful HZ.

Sociodemographic predictors of variation in coverage of the national shingles vaccination programme in England, 2014/15

INTRODUCTION

In September 2013, England introduced a shingles vaccination programme to reduce incidence and severity of shingles in the elderly. This study aims to assess variation in vaccine coverage with regards to selected sociodemographic factors to inform activities for improving equity of the programme.

METHODS

Eligible 70year-olds were identified from a national vaccine coverage dataset in 2014/15 that includes 95% of GPs in England. NHS England Local Team (LT) and index of multiple deprivation (IMD) scores were assigned to patients based on GP-postcode. Vaccine coverage (%) with 95% confidence intervals (CIs), were calculated overall and by LT, ethnicity and IMD, using binomial regression.

RESULTS

Of 502,058 eligible adults, 178,808 (35.6%) had ethnicity recorded. Crude vaccine coverage was 59.5% (95%CI: 59.3-59.7). Coverage was lowest in London (49.6% coverage, 95%CI: 49.0-50.2), and compared to this coverage was significantly higher in all other LTs (+6.3 to +10.4, p<0.001) after adjusting for ethnicity and IMD. Coverage decreased with increasing deprivation and was 8.2% lower in the most deprived (95%CI: 7.3-9.1) compared with the least deprived IMD quintile (64.1% coverage, 95%CI: 63.6-64.6), after adjustment for ethnicity and LT. Compared with White-British (60.7% coverage, 95%CI: 60.5-61.0), other ethnic groups had between 4.0% (Indian) and 21.8% (Mixed: White and Black African) lower coverage. After adjusting for IMD and LT, significantly lower coverage by ethnicity persisted in all groups, except in Mixed: Other, Indian and Bangladeshi compared with White-British.

CONCLUSIONS

After taking geography and deprivation into account, shingles vaccine coverage varied by ethnicity. White-British, Indian and Bangladeshi groups had highest coverage; Mixed: White and Black African, and Black-other ethnicities had the lowest. Patients' ethnicity and IMD are predictors of coverage which contribute to, but do not wholly account for, geographical variation coverage. Interventions to address service-related, sociodemographic and ethnic inequalities in shingles vaccine coverage are required.

Efficacy of gabapentin for prevention of postherpetic neuralgia: study protocol for a randomized controlled clinical trial

BACKGROUND

Postherpetic neuralgia (PHN) is a chronic neuropathic pain that results from alterations of the peripheral nervous system in areas affected by the herpes zoster virus. The symptoms include pain, paresthesia, dysesthesia, hyperalgesia, and allodynia. Despite the availability of pharmacological treatments to control these symptoms, no treatments are available to control the underlying pathophysiology responsible for this disabling condition.

METHODS/DESIGN

Patients with herpes zoster who are at least 50 years old and have a pain score of 4 or higher on a visual analogue scale (VAS) will be recruited. The aim is to recruit 134 patients from the practices of general physicians. Participants will be randomized to receive gabapentin to a maximum of 1800 mg/day for 5 weeks or placebo. Both arms will receive 1000-mg caplets of valacyclovir three times daily for 7 days (initiated within 72 h of the onset of symptoms) and analgesics as needed. The primary outcome measure is the percentage of patients with a VAS pain score of 0 at 12 weeks from rash onset. The secondary outcomes measures are changes in quality of life (measured by the SF-12 questionnaire), sleep disturbance (measured by the Medical Outcomes Study Sleep Scale), and percentage of patients with neuropathic pain (measured by the Douleur Neuropathique in 4 Questions).

DISCUSSION

Gabapentin is an anticonvulsant type of analgesic that could prevent the onset of PHN by its antihypersensitivity action in dorsal horn neurons.

TRIAL REGISTRATION

ISRCTN Registry identifier: ISRCTN79871784 . Registered on 2 May 2013.

European consensus-based (S2k) Guideline on the Management of Herpes Zoster - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV), Part 1: Diagnosis

Herpes zoster (HZ, shingles) is a frequent medical condition which may severely impact the quality of life of affected patients. Different therapeutic approaches to treat acute HZ are available. The aim of this European project was the elaboration of a consensus-based guideline on the management of patients who present with HZ, considering different patient populations and different localizations. This interdisciplinary guideline aims at an improvement of the outcomes of the acute HZ management concerning disease duration, acute pain and quality of life of the affected patients and at a reduction of the incidence of postherpetic neuralgia and other complications. The guideline development followed a structured and predefined process, considering the quality criteria for guidelines development as suggested by the AGREE II instrument. The steering group was responsible for the planning and the organization of the guideline development process (Division of Evidence based Medicine, dEBM). The expert panel was nominated by virtue of clinical expertise and/or scientific experience and included experts from the fields of dermatology, virology/infectiology, ophthalmology, otolaryngology, neurology and anaesthesiology. Recommendations for clinical practice were formally consented during the consensus conference, explicitly considering different relevant aspects. The guideline was approved by the commissioning societies after an extensive internal and external review process. In this first part of the guideline, diagnostic means have been evaluated. The expert panel formally consented recommendations for the management of patients with (suspected) HZ, referring to the assessment of HZ patients, considering various specific clinical situations. Users of the guideline must carefully check whether the recommendations are appropriate for the context of intended application. In the setting of an international guideline, it is generally important to consider different national approaches and legal circumstances with regard to the regulatory approval, availability and reimbursement of diagnostic and therapeutic interventions.

Predicting risk factors for varicella zoster virus infection and postherpetic neuralgia after hematopoietic cell transplantation using ordered logistic regression analysis

To identify risk factors for varicella zoster virus (VZV) infection and postherpetic neuralgia (PHN) after hematopoietic cell transplantation (HCT), we conducted a retrospective chart review of 163 consecutive patients who underwent HCT between November 2004 and July 2014. Overall, the male/female (M/F) ratio was 80/83, median age at HCT was 54 (range 15-69) years, and autologous/allogeneic HCT (auto/allo-HCT) ratio was 71/92. Forty-four patients [M/F, 25/19; median age, 57 (range: 16-68) years; auto/allo-HCT, 26/18] developed VZV infection after HCT. All cases were successfully treated with acyclovir (ACV) or valacyclovir, and there was no VZV-related death. Nine (20%) of the 44 patients [M/F, 5/4; median age, 58 (range: 21-63) years; auto/allo-HCT, 7/2] developed PHN after resolution of zoster. Multivariate ordered logistic analysis identified receiving immunosuppressive therapy at the cessation of ACV [odds ratio (OR) = 74.53; 95% confidence interval (CI) = 6.99-794.32; P = 0.0004] as a risk factor for VZV infection and PHN in allo-HCT recipients. However, in auto-HCT recipients, only advanced age was identified as a risk factor (OR = 1.06, 95% CI = 1.002-1.127, P = 0.0429). Our findings indicate receiving immunosuppressive therapy at the cessation of ACV is a significant risk factor for allo-HCT recipients, while advanced age is a significant risk factor for auto-HCT recipients.

Vaccination of special populations: Protecting the vulnerable

One of the strategic objectives of the 2011-2020 Global Vaccine Action Plan is for the benefits of immunisation to be equitably extended to all people. This approach encompasses special groups at increased risk of vaccine-preventable diseases, such as preterm infants and pregnant women, as well as those with chronic and immune-compromising medical conditions or at increased risk of disease due to immunosenescence. Despite demonstrations of effectiveness and safety, vaccine uptake in these special groups is frequently lower than expected, even in developed countries with vaccination strategies in place. For example, uptake of the influenza vaccine in pregnancy rarely exceeds 50% in developed countries and, although data are scarce, it appears that only half of preterm infants are up-to-date with routine paediatric vaccinations. Many people with chronic medical conditions or who are immunocompromised due to disease or aging are also under-vaccinated. In the US, coverage among people aged 65years or older was 67% for the influenza vaccine in the 2014-2015 season and 55-60% for tetanus and pneumococcal vaccines in 2013, while the coverage rate for herpes zoster vaccination among those aged 60years or older was only 24%. In most other countries, rates are far lower. Reasons for under-vaccination of special groups include fear of adverse outcomes or illness caused by the vaccine, the inconvenience (and in some settings, cost) of vaccination and lack of awareness of the need for vaccination or national recommendations. There is also evidence that healthcare providers' attitudes towards vaccination are among the most important influences on the decision to vaccinate. It is clear that physicians' adherence to recommendations needs to be improved, particularly where patients receive care from multiple subspecialists and receive little or no care from primary care providers.

European consensus-based (S2k) Guideline on the Management of Herpes Zoster - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV), Part 2: Treatment

Herpes zoster (HZ, shingles) is a frequent medical condition which may severely impact the quality of life of affected patients. Different therapeutic approaches to treat acute HZ are available. The aim of this European project was the elaboration of a consensus-based guideline on the management of patients who present with HZ, considering different patient populations and different localizations. This interdisciplinary guideline aims at an improvement of the outcomes of the acute HZ management concerning disease duration, acute pain and quality of life of the affected patients and at a reduction in the incidence of postherpetic neuralgia (PHN) and other complications. The guideline development followed a structured and pre-defined process, considering the quality criteria for guidelines development as suggested by the AGREE II instrument. The steering group was responsible for the planning and the organization of the guideline development process (Division of Evidence-Based Medicine, dEBM). The expert panel was nominated by virtue of clinical expertise and/or scientific experience and included experts from the fields of dermatology, virology/infectiology, ophthalmology, otolaryngology, neurology and anaesthesiology. Recommendations for clinical practice were formally consented during the consensus conference, explicitly considering different relevant aspects. The guideline was approved by the commissioning societies after an extensive internal and external review process. In this second part of the guideline, therapeutic interventions have been evaluated. The expert panel formally consented recommendations for the treatment of patients with HZ (antiviral medication, pain management, local therapy), considering various clinical situations. Users of the guideline must carefully check whether the recommendations are appropriate for the context of intended application. In the setting of an international guideline, it is generally important to consider different national approaches and legal circumstances with regard to the regulatory approval, availability and reimbursement of diagnostic and therapeutic interventions.

Increasing incidence associated with herpes zoster infection in British Columbia, Canada

BACKGROUND

Recent studies have shown an increasing incidence of herpes zoster (HZ) infection, which may be related to the introduction of varicella vaccination programs in children. We examined the epidemiology and treatment costs of HZ and post-herpetic neuralgia (PHN) over time in British Columbia, Canada.

METHODS

The cohort consisted of all cases with HZ infection from January 1, 1997 and December 31, 2012. Incident zoster was defined as a case (ICD-9 053 or ICD-10 B02) without a previous episode of HZ or PHN in the previous 12 months. We determined the incidence for HZ and PHN and the age-sex standardized rate for the overall population. We determined the association between the varicella vaccination program and increased HZ rates by evaluating the rate ratios in the publicly-funded varicella vaccine period compared to the non-publicly funded period in a regression model. We evaluated the hospitalization rates, treatment by GPs and their associated yearly costs for HZ and PHN.

RESULTS

HZ incidence increased for the entire study period from 3.2 per 1000 population in 1997 to 4.5 in 2012. HZ rates were higher for females than males and all age groups had an increased incidence rate, except the 0-9 year olds, where the rate decreased. Crude and age-sex standardized incidence rates of PHN demonstrated very similar patterns to HZ incidence. Based on the regression model, rates of HZ were higher in the older individuals. No significant increase with HZ incidence was seen during the publically funded varicella vaccination program compared to the non-publicly funded period. From 1997 to 2012, the annual HZ-related costs associated with hospitalizations and GP visits were over $CDN4.9 million and $CDN537,286, respectively; treatment costs for hospitalizations have increased significantly over time. Majority of PHN-related cases are managed by GPs, with a steady increase over time in number of cases and associated annual costs.

CONCLUSIONS

The incidence of zoster and PHN is increasing with time, particularly in the elderly population and the risk is greater in the over 65 year olds. Treatment costs for both HZ and PHN represent a significant burden on the Canadian healthcare system.

Pain, Itch, Quality of Life, and Costs after Herpes Zoster

BACKGROUND

Herpes zoster (HZ) and postherpetic neuralgia are known to have a profound effect on the patient's quality of life, but the incidence and severity of itch and its relation with pain and quality of life in the long term are still relatively unknown.

OBJECTIVE

The aim of this study was to measure the presence and severity of pain and itch and impact on quality of life in patients over 50 years old with HZ.

METHODS

We enrolled 661 patients with HZ in this 12-month observational study. Patient data were collected via a web-based questionnaire. Outcomes were pain, itch, burden of illness, impact on patient's daily life, impact on quality of life, and healthcare costs.

RESULTS

At inclusion, 94% of patients reported any pain, 74.3% significant pain, and 26% severe pain. After 3 months, 18.8% of patients suffered from postherpetic neuralgia. At inclusion, 70.8% of patients had any itch, 39.2% significant itch, and 7.3% severe itch. The occurrence of pain increases costs and has a high impact on the quality of life, lowering EQ-5D scores by an average of 18%. In contrast, itch has little effect on the quality of life.

CONCLUSIONS

Pain and itch are highly prevalent months after HZ. Pain caused by HZ has a large impact on quality of life, burden of illness, impact on daily life, and health care costs for these patients. The impact of itch on quality of life is relatively small.

Postherpetic neuralgia: epidemiology, pathophysiology, and pain management pharmacology

Herpes zoster, also known as shingles, is a distinctive clinical condition caused by the reactivation of latent varicella zoster (chickenpox) virus following an initial infection. Approximately 1 million cases of herpes zoster occur annually in the US, and one in every three people develops herpes zoster during their lifetime. Postherpetic neuralgia is a neuropathic pain syndrome characterized by pain that persists for months to years after resolution of the herpes zoster rash. It stems from damage to peripheral and central neurons that may be a byproduct of the immune/inflammatory response accompanying varicella zoster virus reactivation. Patients with postherpetic neuralgia report decreased quality of life and interference with activities of daily living. Approaches to management of postherpetic neuralgia include preventing herpes zoster through vaccination and/or antiviral treatment, and administering specific medications to treat pain. Current guidelines recommend treatment of postherpetic neuralgia in a hierarchical manner, with calcium channel α2-δ ligands (gabapentin and pregabalin), tricyclic antidepressants (amitriptyline, nortriptyline, or desipramine), or topical lidocaine patches as first-line drugs. The safety and tolerability of pharmacologic therapies for pain are important issues to consider as postherpetic neuralgia affects primarily an older population. Patients should be educated on appropriate dosing, titration if applicable, the importance of adherence to treatment for optimal effectiveness, and possible side effects. Health-care professionals play a key role in helping to ameliorate the pain caused by postherpetic neuralgia through early recognition and diligent assessment of the problem; recommending evidence-based treatments; and monitoring treatment adherence, adverse events, responses, and expectations. Nurse practitioners are especially crucial in establishing communication with patients and encouraging the initiation of appropriate pain-relieving treatments.

Efficacy of continuous epidural block in acute herpes zoster: Incidence and predictive factors of postherpetic neuralgia, a retrospective single-center study

The aim of the present study was to investigate efficacy of continuous epidural block for prevent postherpetic neuralgia (PHN) progression in cases of acute herpes zoster with severe pain and also to identify predictive factors for PHN in such conditions.We retrospectively analyzed the clinical data of patients with herpes zoster who underwent continuous epidural block between March 2013 and October 2015. Time points were set as 1 month, 3 months, and 6 months after zoster onset. PHN was defined as the presence of pain with NRS ≥3 at certain time points.The incidence of developing PHN was 38.1%, 27.0%, and 19.0% 1 month, 3 months, and 6 months after zoster onset, respectively. Age and duration of catheterization were predictive factors for PHN at 1 month. Age, duration of catheterization, and NRS at first visit were identified as predictive factors for PHN at 3 months. Presence of diabetes, duration of catheterization, and NRS during catheterization were significant predictive factors for PHN at 6 months.The incidence of PHN is higher in zoster patients with severe pain that requires continuous epidural block compared to incidence in the general population. Advanced age and severe initial pain intensity were predictive factors of PHN development. Prolonged catheterization resulting from weak response to treatment strongly suggested progression to PHN.

Quantification of risk factors for postherpetic neuralgia in herpes zoster patients: A cohort study

OBJECTIVE

To investigate risk factors for postherpetic neuralgia, the neuropathic pain that commonly follows herpes zoster.

METHODS

Using primary care data from the Clinical Practice Research Datalink, we fitted multivariable logistic regression models to investigate potential risk factors for postherpetic neuralgia (defined as pain ≥90 days after zoster, based on diagnostic or prescription codes), including demographic characteristics, comorbidities, and characteristics of the acute zoster episode. We also assessed whether the effects were modified by antiviral use.

RESULTS

Of 119,413 zoster patients, 6,956 (5.8%) developed postherpetic neuralgia. Postherpetic neuralgia risk rose steeply with age, most sharply between 50 and 79 years (adjusted odds ratio [OR] for a 10-year increase, 1.70, 99% confidence interval 1.63-1.78). Postherpetic neuralgia risk was higher in women (6.3% vs 5.1% in men: OR 1.19, 1.10-1.27) and those with severely immunosuppressive conditions, including leukemia (13.7%: 2.07, 1.08-3.96) and lymphoma (12.7%: 2.45, 1.53-3.92); autoimmune conditions, including rheumatoid arthritis (9.1%: 1.20, 0.99-1.46); and other comorbidities, including asthma and diabetes. Current and ex-smokers, as well as underweight and obese individuals, were at increased risk of postherpetic neuralgia. Antiviral use was not associated with postherpetic neuralgia (OR 1.04, 0.97-1.11). However, the increased risk associated with severe immunosuppression appeared less pronounced in patients given antivirals.

CONCLUSIONS

Postherpetic neuralgia risk was increased for a number of patient characteristics and comorbidities, notably with age and among those with severe immunosuppression. As zoster vaccination is contraindicated for patients with severe immunosuppression, strategies to prevent zoster in these patients, which could include the new subunit zoster vaccine, are an increasing priority.

Efficacy of low dose gabapentin in acute herpes zoster for preventing postherpetic neuralgia: a prospective controlled study

Postherpetic neuralgia (PHN) is a sequela of herpes zoster that adversely affects quality of life seriously. The risk factors for PHN are well known but the effective interventions that reduce the incidence of PHN are less studied. The objective of this study is to evaluate the efficacy of treatment with gabapentin in patients with acute herpes zoster for preventing PHN. We performed a prospective randomized controlled study of 120 participants diagnosed with acute herpes zoster, aged 50 and over and complaining moderate to severe pain. All patients were treated with valacyclovir and acetaminophen. Half of the participants were assigned to the gabapentin group and received gabapentin 300 mg three times a day additionally. The intensity of pain at every visit and the incidence of PHN in both groups were measured. Total 52 and 49 patients in the gabapentin group and the control group, respectively, had completed 12 weeks of follow-up period. Although the incidence of PHN was higher in the control group, the difference was not statistically significant (6.1% vs. 3.8%, p = 0.67). Our results indicate that the use of low-dose gabapentin in acute herpes zoster seems not effective in the prevention of PHN.

Non-invasive measurement of skin autofluorescence to evaluate diabetic complications

Although the accumulation of advanced glycation end-products (AGEs) of the Maillard reaction in our body is reported to increase with aging and is enhanced by the pathogenesis of lifestyle-related diseases such as diabetes, routine measurement of AGEs is not applied to regular clinical diagnoses due to the lack of conventional and reliable techniques for AGEs analyses. In the present study, a non-invasive AGEs measuring device was developed and the association between skin AGEs and diabetic complications was evaluated. To clarify the association between the duration of hyperglycemia and accumulation of skin fluorophores, diabetes was induced in mice by streptozotocin. As a result, the fluorophore in the auricle of live mice was increased by the induction of diabetes. Subsequent studies revealed that the fingertip of the middle finger in the non-dominant hand is suitable for the measurement of the fluorescence intensity by the standard deviation value. Furthermore, the fluorescence intensity was increased by the presence of diabetic microvascular complications. This study provides the first evidence that the accumulation of fluorophore in the fingertip increases with an increasing number of microvascular complications, demonstrating that the presence of diabetic microvascular complications may be predicted by measuring the fluorophore concentration in the fingertip.