Postherpetic neuralgia in the elderly

[Neurosurgical treatment of postherpetic neuralgia]

Postherpetic neuralgia is a chronic and debilitating condition that can occur following an episode of herpes zoster (shingles). It is characterized by severe, persistent pain in the area where the shingles rash occurred. While various treatment approaches exist, including medications and non-invasive therapies, some cases of postherpetic neuralgia may require neurosurgical intervention. Neurosurgical treatment options for postherpetic neuralgia aim to alleviate the pain by targeting the affected nerves or neural pathways. One common approach is spinal cord stimulation (SCS). In SCS, electrodes are implanted along the spinal cord, and electrical impulses are delivered to interfere with the transmission of pain signals. This technique can modulate pain perception and significantly reduce the intensity and frequency of postherpetic neuralgia symptoms. Neurosurgical treatment of postherpetic neuralgia is typically considered when conservative measures have failed to provide sufficient relief. However, it is crucial for patients to undergo a comprehensive evaluation and consultation with a neurosurgeon to determine the most appropriate treatment approach based on their specific condition and medical history. The risks, benefits, and potential outcomes of neurosurgical interventions should be carefully discussed between the patient and their healthcare provider to make an informed decision.

CT-guided paravertebral injection of doxorubicin for treatment of postherpetic neuralgia: a database-based retrospective stratified study

Objective

This study explored the impact of different doeses of doxorubicin in CT-guided transvertebral foraminal injections for postherpetic neuralgia (PHN) treatment and the impact of 0.5% doxorubicin treatment on patients with different disease courses and lesion locations.

Methods

This retrospective study included 291 patients with PHN who received CT-guided doxorubicin injection at West China Hospital between April 2014 and February 2020.

Results

A total of 228 patients received 0.5% doxorubicin treatment and 63 received 0.33% doxorubicin. Both groups showed significantly improvement in visual analogue scale (VAS) and Brief Pain Inventory (BPI) scores. The 0.5% doxorubicin group demonstrated significant lower VAS scores at 6 and 12 months after surgery (all p < 0.001) and a significant lower score on the BPI at 6 and 12 months than the 0.33% doxorubicin group (all p < 0.05). Stratified analysis of 0.5% doxorubicin demonstrated a significant reduction in VAS score at 1 week, 3 months, 6 months, and 12 months after treatment compared to baseline (all p < 0.05) and significant improvements in BPI score after treatment compared to baseline (p < 0.05). The VAS score of the chest group was significant higher than facial, neck and upper limbs and abdomen groupsin groups 1 week after surgery (all p < 0.05). Various aspects of quality of life, including daily life, enjoyment of life, sleep, relationships, work, walking ability, and emotions, significantly decreased after surgery (p < 0.05). Especially in sleep duration, there was an increase in patients reporting intermediate sleep (4-7 h) and a proportion achieving a normal sleep duration of ≥7 h. And no significant differences of BPI were observed among different affected locations. The incidence of adverse events in the 0.5% doxorubicin group and 0.33% doxorubicin group was 8.78 and 6.34%, respectively.

Conclusion

CT-guided doxorubicin injection therapy has the potential to alleviate pain and enhance the quality of life in patients with PHN. Notably, the use of a 0.5% doxorubicin concentration yields more pronounced pain relief compared to a 0.33% concentration. While longer durations of PHN and specific affected sites may influence the response to treatment, the overall improvements in quality of life remain consistent.

Patterns of use of recombinant zoster vaccine among commercially-insured immunocompetent and immunocompromised adults 50-64 years old in the United States

PURPOSE

The Centers for Disease Control and Prevention (CDC) recommends recombinant zoster vaccination (RZV) for adults ≥ 50 years to prevent herpes zoster (HZ) and its sequelae. Initially, no distinct recommendation was made for immunocompromised adults, who experience higher HZ rates and more severe outcomes. We characterized receipt of first RZV dose (initiation) and both doses (completion) over time, and the impact of immune function on RZV uptake among adults aged 50-64 years in the United States.

METHODS

We identified RZV claims from the IBM MarketScan database between 1/1/2018 and 12/31/2019. We characterized immunocompromised enrollees as having malignancy, HIV, solid organ transplant, primary immunosuppression, or medication-induced immunosuppression using inpatient, outpatient, and prescription claims in the 6 months prior to study start. We evaluated patterns of vaccine uptake by demographic and healthcare access characteristics and immune status.

RESULTS

The cumulative incidence of RZV initiation during the study period was 10.0%. Incidence increased with age and number of medical office visits, and was higher among women, urban residents, high-deductible insurance beneficiaries, and those who were immunocompromised compared to immunocompetent. Among immunocompromised adults, RZV initiation was highest among those with HIV and primary immunodeficiencies. Of those who initiated RZV, 89.5% received both doses. RZV completion was highest among those who received the first dose at a pharmacy. Most enrollees (88.6%) who completed RZV vaccination did so within the recommended dosing schedule.

CONCLUSIONS

RZV uptake was low in the two years since the CDC recommendation, and differed by demographic, healthcare access, and clinical characteristics. Initiation rates were higher among immunocompromised adults compared to immunocompetent adults, despite no CDC recommendation for vaccination in these groups during the study period. The CDC has since recommended RZV for immunocompromised individuals, and our findings may inform efforts to increase RZV uptake in individuals at higher risk of severe disease.

The Effectiveness of Various Types of Electrical Stimulation of the Spinal Cord for Chronic Pain in Patients with Postherpetic Neuralgia: A Literature Review

Introduction

Postherpetic neuralgia (PHN) is a severe condition that remains a challenge to treat. Spinal cord stimulation (SCS) is used in cases of insufficient efficacy of conservative treatment. However, in contrast to many other neuropathic pain syndromes, there is a huge problem in reaching long-term stable pain relief in patients with PHN using conventional tonic SCS. The objective of this article was to present a review of the current management strategies of PHN, their efficacy, and safety.

Materials and Methods

We searched for articles containing the keywords "spinal cord stimulation AND postherpetic neuralgia," "high-frequency stimulation AND postherpetic neuralgia," "burst stimulation AND postherpetic neuralgia" and "dorsal root ganglion stimulation AND postherpetic neuralgia" in Pubmed, Web of Science, and Scopus databases. The search was limited to human studies published in the English language. There were no publication period limitations. Bibliographies and references of selected publications on neurostimulation for PHN were further manually screened. The full text of each article was studied once the abstract was analyzed by the searching reviewer and found appropriate. The initial search yielded 115 articles. Initial screening based on abstract and title allowed us to exclude 29 articles (letters, editorials, and conference abstracts). The full-text analysis allowed us to exclude another 74 articles (fundamental research articles, research utilizing animal subjects, and systemic and nonsystemic reviews) and results of PHN treatment presented with other conditions, leaving 12 articles for the final bibliography.

Results

12 articles reporting on the treatment of 134 patients with PHN were analyzed, with a disproportionally large amount of traditional SCS treatment than that to alternative SCS: DRGS (13 patients), burst SCS (1 patient), and high-frequency SCS (2 patients). Long-term pain relief was achieved in 91 patients (67.9%). The mean VAS score improvement was 61.4% with a mean follow-up time of 12.85 months. Although the number of patients in alternative SCS studies was very limited, almost all of them showed good responses to therapy with more than 50% VAS improvement and reduction of analgesic dosage. The article contains a review analysis of 12 articles concerning the current methods of treatment for postherpetic neuralgia including conservative treatment, spinal cord stimulation, and novel neuromodulation strategies. Available information on the pathophysiology of PHN and the effect or stimulation on its course, together with a number of technical nuances concerning various types of neurostimulation are also elucidated in this article. A number of alternative invasive treatments of PHN are also discussed.

Conclusions

Spinal cord stimulation is an established treatment option for patients with pharmacologically resistant PHN. High-frequency stimulation, burst stimulation, and dorsal root ganglion stimulation are promising options in the management of PHN due to the absence of paresthesias which can be painful for patients with PHN. But more research is still required to recommend the widespread use of these new methods.

Short-term spinal cord stimulation is an effective therapeutic approach for herpetic-related neuralgia—A Chinese nationwide expert consensus

Purpose

Short-term spinal cord stimulation (st-SCS) has been widely used to treat herpetic-related neuralgia (HN) in China for several years, but is still heavily debated as it has no strong evidence in clinical application. Therefore, a questionnaire survey among the Chinese pain specialist workgroup of the Chinese Neuromodulation Society and Chinese Medical Doctor Association was carried out to achieve a consensus about the clinical use of st-SCS for HN treatment.

Methods

The contents of the questionnaire include basic information about doctors (hospital level, work experience, training, procedure numbers, etc.), efficacy, indications, and contraindications of st-SCS, operation conditions, and preoperative preparation of st-SCS, and the prospect of the st-SCS procedure. Initially, the survey was conducted on 110 experts who have practiced the st-SCS procedure from all over the provinces in China. Finally, valuable data was calculated from the 110 questionnaires excluding the doctors with <1 year of experience of st-SCS, <10 cases of procedures per year, and no standard training in SCS technique.

Results

Based on the 110 questionnaires, it is estimated that 5,000 to 10,000 cases of electrical stimulation are carried out nationwide each year. Sixty-nine valid questionnaires acquired from senior pain physicians were more valuable and specialized in the efficacy, indications, and contraindications of st-SCS for HN. It was commonly agreed (97.10%) that the HN patients with <3 months will obtain good effectiveness (patient satisfaction rate ≥50%). Almost all (98.55%) agreed that st-SCS can be used in SHN patients, there was a common agreement (72.46%) that AHN patients are an indication of st-SCS, and more than half agreement (53.62%) that st-SCS may be fit for early PHN (3–6 months). A common agreement (79.71%) was achieved that more than half of HN patients had the experience of nerve block or nerve pulsed RF. A similarly large number of experts 57/69 (82.61%) agreed that an 80% paresthesia coverage should be achieved at the test stimulation and 57/69 (82.61%) agreed that the treatment of st-SCS need be persistent for 1–2 weeks.

Conclusions

Early HN patients can get an effective outcome from the treatment of st-SCS and maybe the indication of st-SCS. Moreover, standardized training for pain physicians and basic research and clinical studies are warranted.

Comparing the efficacy and safety of short-term spinal cord stimulation and pulsed radiofrequency for zoster-related pain: A systematic review and meta-analysis

BACKGROUND

Pulsed radiofrequency (PRF) is a commonly used method for the treatment of zoster-related pain in the clinic. However, PRF therapy has a high recurrence rate and many adverse reactions. Recent studies have shown that short-term spinal cord stimulation (stSCS) can effectively alleviate zoster-related pain. Due to the lack of evidence, it is unclear whether stSCS is superior to PRF in the efficacy of treating zoster-related pain.

OBJECTIVE

This study aimed to compare the efficacy and safety of stSCS and PRF for zoster-related pain.

METHODS

We searched seven electronic databases from the establishment of the database to January 2021. Related randomized controlled trials were included in this meta-analysis. After extracting the data and evaluating the methodological quality of the included trials, the outcome indicators were statistically analyzed by using RevManV.5.3.

RESULTS

This meta-analysis included 6 trials with a total of 509 patients. Compared with PRF group, stSCS group showed lower pain intensity (standardized mean difference=-0.83, 95%CI [-1.37, -0.30], P=.002), better sleep quality (mean difference=-1.43, 95%CI [-2.29, -0.57], P=.001), lower pain rating index scores, and less incidence of adverse events (RR=0.32, 95%CI [0.12, 0.83], P<.05). However, the efficacies of PRF and stSCS for treating postherpetic neuralgia were consistent in the response rate (RR= 1.10, 95% CI [0.82, 1.48], P=.51) and the complete remission rate (RR=1.05, 95% CI [0.66, 1.68], P=.84).

CONCLUSIONS

In this study, stSCS showed a better analgesic effect and higher safety than PRF. Our meta-analysis results suggested that stSCS may be a feasible and safe invasive treatment for zoster-related pain. However, high-quality, randomized controlled trials with large sample sizes are needed to further verify our conclusions.

Pattern of Skin Diseases in Geriatric Population: Our Year-Long Experience from Nepal

Introduction:

The average life span has increased by about two decades in Nepal in last 30 years. With increasing longevity, geriatric health care is gaining much more importance. The statistical data regarding the geriatric skin disorders in Nepalese population is limited. The aim of this study to look for the patterns of skin diseases in the geriatric population of Nepal.

Methodology:

This is a retrospective, descriptive study where we reviewed the database of patients visiting the dermatology outpatient department of multispeciality teaching hospital in Nepal from August 2016 to July 2017. All patients from the age of 60 and above were included in the study. Data was analyzed using SPSS version 20. Chi square test was done where relevant.

Result:

Total of 918 patients were included in the study with mean age of 69 years. Most common presentation was that of dermatitis (32.2%) which was followed by infectious condition (29.4%), pruritus (7.4%), psoriasis (4.6%), urticaria (3.9%), miliaria (3.9%) and others. Among the dermatitis, 23% of the patients had hand or feet eczema and 23% had sebohrreic dermatitis. Variability according to weather was noticed with in presentation of sebohrreic dermatitis, dermatophytic infections, miliaria and herpes zoster.

Conclusion:

This study concludes that dermatitis, infections and pruritus are the most significant dermatological morbidities in our population. It highlights the need of zoster vaccine for our elderly population as it is not a part of the routine vaccination scheme in Nepal.

The brain's structural differences between postherpetic neuralgia and lower back pain

The purpose is to explore the brain's structural difference in local morphology and between-region networks between two types of peripheral neuropathic pain (PNP): postherpetic neuralgia (PHN) and lower back pain (LBP). A total of 54 participants including 38 LBP and 16 PHN patients were enrolled. The average pain scores were 7.6 and 7.5 for LBP and PHN. High-resolution structural T1 weighted images were obtained. Both grey matter volume (GMV) and morphological connectivity (MC) were extracted. An independent two-sample t-test with false discovery rate (FDR) correction was used to identify the brain regions where LBP and PHN patients showed significant GMV difference. Next, we explored the differences of MC network between LBP and PHN patients and detected the group differences in network properties by using the two-sample t-test and FDR correction. Compared with PHN, LBP patients had significantly larger GMV in temporal gyrus, insula and fusiform gyrus (p < 0.05). The LBP cohort had significantly stronger MC in the connection between right precuneus and left opercular part of inferior frontal gyrus (p < 0.05). LBP patients had significantly stronger degree in left anterior cingulate gyrus and left rectus gyrus (p < 0.05) while had significantly weaker degree than PHN patients in left orbital part of middle frontal gyrus, left supplementary motor area and left superior parietal lobule (p < 0.05). LBP and PHN patients had significant differences in the brain's GMV, MC, and network properties, which implies that different PNPs have different neural mechanisms concerning pain modulation.

Herpes zoster in outpatient departments of healthcare centers in India: a review of literature

In India, although incidence of Herpes zoster has not been assessed, regional cases have been reported. We revisited the peer-reviewed literature on clinical cases of HZ to depict the trends in population characteristics, disease presentation, and predisposing factors for the disease in India. Systematically conducted literature search yielded 27 studies, published between January 2011 and May 2020, reporting 3124 HZ clinical cases, with high proportions in older adults (>50 years of age: 15.0-81.3%). Thoracic dermatome was consistently reported as the most frequent site affected by HZ (38.9-71.0%). Post-herpetic neuralgia and secondary bacterial infections were the two most frequent complications (10.2-54.7% and 3.5-21.0%, respectively). Despite the paucity of data and gaps in the reporting of HZ cases, available evidence indicate that the disease causes an important burden to older adults in India, suggesting that preventive strategies, along with recommendations to healthcare practitioners, can help mitigate the burden of HZ.

Ultrasound-guided peripheral nerve interventions for common pain disorders

There are a number of common pain disorders that can be managed effectively by injections around or ablation of peripheral nerves. Ultrasound is a universally available imaging tool, is safe, cost-effective, and is excellent in imaging many peripheral nerves and guiding needles to the site of the nerves. This article aims to present an overview of indications and techniques of such procedures that can be effectively performed by a radiologist.

Pulsed Radiofrequency of the Trigeminal Ganglion for Treating Postherpetic Neuralgia of the Ophthalmic Branch

Postherpetic neuralgia (PHN) is a painful, long-lasting condition as a consequence of nerve damage resulting from a herpes zoster infection. Although there are many different treatments available to reduce pain duration and severity, PHN is often refractory to them and no single therapy shows an effective cure for all cases of PHN, especially for those involving the ophthalmic branch of the trigeminal nerve. Pulsed radiofrequency (PRF) is a minimally invasive procedure for pain treatment that has been practiced over the past decade. However, its clinical efficacy and safety for treating PHN involving the ophthalmic branch of the trigeminal nerve have not been evaluated. Objective. This study aimed to evaluate the efficacy and safety of PRF for treating PHN involving the ophthalmic branch of the trigeminal ganglion. Study Design. An observational study. Setting. All patients received PRF of the ophthalmic branch of the trigeminal nerve, pain intensity was assessed by a visual analogue scale (VAS), and complications before and after PRF stimulation were noted. Methods. Thirty-two patients with PHN of the ophthalmic branch were treated by PRF of the ophthalmic branch with controlled temperature at 42°C for 8 min. Pain relief, corneal reflex, sleep quality, and satisfaction were assessed for all patients. Results. Thirty out of 32 patients (93.75%) reported significant pain reduction after PRF treatment. Twenty-eight of them (87.5%) were satisfied with their sleep and obtained a pain score lower than 3 following the procedure. Only two patients had a recurrence of the severe burning pain and returned to the hospital for other medical therapies 2 weeks after the PRF procedure. No patient lost the corneal reflex. Limitations. This study is an observational study and a nonprospective trial with a short-term follow-up period. Conclusion. PRF of the trigeminal ganglion of the ophthalmic branch can significantly reduce pain sensation and improve sleep quality and satisfaction for PHN of the ophthalmic branch.

Advances and Perspectives in the Management of Varicella-Zoster Virus Infections

Varicella-zoster virus (VZV), a common and ubiquitous human-restricted pathogen, causes a primary infection (varicella or chickenpox) followed by establishment of latency in sensory ganglia. The virus can reactivate, causing herpes zoster (HZ, shingles) and leading to significant morbidity but rarely mortality, although in immunocompromised hosts, VZV can cause severe disseminated and occasionally fatal disease. We discuss VZV diseases and the decrease in their incidence due to the introduction of live-attenuated vaccines to prevent varicella or HZ. We also focus on acyclovir, valacyclovir, and famciclovir (FDA approved drugs to treat VZV infections), brivudine (used in some European countries) and amenamevir (a helicase-primase inhibitor, approved in Japan) that augur the beginning of a new era of anti-VZV therapy. Valnivudine hydrochloride (FV-100) and valomaciclovir stearate (in advanced stage of development) and several new molecules potentially good as anti-VZV candidates described during the last year are examined. We reflect on the role of antiviral agents in the treatment of VZV-associated diseases, as a large percentage of the at-risk population is not immunized, and on the limitations of currently FDA-approved anti-VZV drugs. Their low efficacy in controlling HZ pain and post-herpetic neuralgia development, and the need of multiple dosing regimens requiring daily dose adaptation for patients with renal failure urges the development of novel anti-VZV drugs.

Efficacy of intermittent epidural dexamethasone bolus for zoster-associated pain beyond the acute phase

Herpes zoster develops when latent varicella zoster virus is reactivated in the trigeminal or dorsal root ganglions. Zoster-associated pain (ZAP) is neuropathic pain caused by the herpes zoster virus. Histological studies of postherpetic neuralgia patients suggest that inflammation is involved in ZAP. The effectiveness of local anesthetic and steroid epidural injections in ZAP patients has been reported. However, most studies included patients with acute herpes zoster, and the safety and therapeutic effects of different doses of epidural steroids in ZAP patients remain elusive. In this study, we randomly assigned 42 patients with severe ZAP beyond the acute phase, as determined by a numeric rating scale (NRS) score ≥7, to receive continuous epidural infusion of local anesthetics with either a one-time 5-mg dose or intermittent repeated doses (15 mg total) of dexamethasone. We found that intermittent repeated epidural dexamethasone bolus resulted in reduced NRS scores and an increased likelihood of complete remission in ZAP patients without any adverse effects. Thus, our results suggest that intermittent repeated epidural dexamethasone administration is safe and effective for treatment of ZAP beyond the acute phase.

Chronic pain: a review of its epidemiology and associated factors in population-based studies

Chronic pain is a common, complex, and distressing problem that has a profound impact on individuals and society. It frequently presents as a result of a disease or an injury; however, it is not merely an accompanying symptom, but rather a separate condition in its own right, with its own medical definition and taxonomy. Studying the distribution and determinants of chronic pain allows us to understand and manage the problem at the individual and population levels. Targeted and appropriate prevention and management strategies need to take into account the biological, psychological, socio-demographic, and lifestyle determinants and outcomes of pain. We present a narrative review of the current understanding of these factors.

Measuring herpes zoster disease burden in São Paulo, Brazil: a clinico-epidemiological single-center study

OBJECTIVES

Herpes zoster is characterized by acute neuritis and post-herpetic neuralgia. Currently, data concerning the zoster-associated impact on quality of life and healthcare resource utilization in Brazil are scarce. This study measured the zoster-associated burden in a Brazilian population.

METHODS

This was a prospective, observational, single-cohort study conducted in a primary hospital's emergency room in São Paulo, Brazil. Patients enrolled at various timepoints during a zoster episode were followed over 180 days. The Zoster Brief Pain Inventory and the Initial Zoster Impact Questionnaire assessed zoster-associated pain. The EuroQoL assessed the impact of herpes zoster and/or zoster-associated pain on quality of life. Healthcare resource utilization was assessed by patient-reported questionnaires.

RESULTS

One-hundred forty-six zoster patients were enrolled [mean (SD) age of 69.9 (10.9) years]. Mean (SD) worst pain scores decreased from 5.3 (3.5) at baseline to 1.9 (3.0) 180 days following rash onset. Mean (SD) EuroQoL scores significantly decreased from 0.9 (0.2) before rash appearance to 0.7 (0.2) after rash onset (p<0.001), followed by gradual improvements in quality of life over 180 days, with pre-herpes zoster quality of life achieved at the end of the observation period. The majority of patients purchased prescription medications (89.7%) and required doctor's office visits (65.8%) for zoster episodes.

CONCLUSIONS

Herpes zoster is associated with a significant disease burden, including zoster-associated pain, impaired quality of life and increased healthcare resource utilization in Brazil. These results support the implementation of early intervention and prevention programs such as vaccinations to reduce the herpes zoster-associated disease burden in Brazil.

Evaluation of the Population Pharmacokinetic Properties of Lidocaine and its Metabolites After Long-Term Multiple Applications of a Lidocaine Plaster in Post-Herpetic Neuralgia Patients

Background and Objectives

Lidocaine 5% medicated plaster is the first lidocaine containing product for chronic use. As no previous investigations have been conducted to evaluate the population pharmacokinetics of long-term exposure to lidocaine 5% medicated plasters, further insights into the evaluation of the pharmacokinetic properties of lidocaine and its metabolites were needed for the assessment of its safety.

Methods

The population pharmacokinetic properties of lidocaine and its metabolites were evaluated after multiple applications of lidocaine 5% medicated plasters based on data collected for up to 14.5 months from two phase III clinical trials (up to 2.5 months in the first trial, and up to 12 months in a follow-up trial) in post-herpetic neuralgia patients. Modeling was performed using nonlinear mixed effects as implemented in NONMEM^® (nonlinear mixed-effect modeling) v.5. A stepwise forward inclusion and backward elimination procedure were used for covariate model building.

Results

The model provides reliable estimates of the pharmacokinetic behavior of lidocaine after medicated plaster application. It was validated using simulations and showed adequate predictive properties. Apparent Clearance was estimated to be 48 L/h after application of two or fewer plasters, whereas its value increased to 67 L/h after application of three plasters. Model-based simulations predicted no accumulation of lidocaine or any of its metabolites after long-term exposure of three simultaneous plasters up to 1 year. The variability explained by adding covariates into the model for the long-term exposures of lidocaine following one plaster or three simultaneous plaster applications was found to be very small with respect to the overall between-subject variability.

Conclusions

In conclusion, exposure to lidocaine after the application of the lidocaine medicated plaster was found to be primarily affected by the number of plasters simultaneously applied, i.e., it increased with the number of applied patches, but less than proportionally. No clinically relevant effect of other covariates was found to affect the exposure to lidocaine or its metabolites. As no accumulation was predicted by the model, long-term exposure to lidocaine and its metabolites is not expected to lead to any safety concerns in post-herpetic neuralgia patients.

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.

Recommendations of the Advisory Committee on Immunization Practices for Use of Herpes Zoster Vaccines

On October 20, 2017, Zoster Vaccine Recombinant, Adjuvanted (Shingrix, GlaxoSmithKline, [GSK] Research Triangle Park, North Carolina), a 2-dose, subunit vaccine containing recombinant glycoprotein E in combination with a novel adjuvant (AS01B), was approved by the Food and Drug Administration for the prevention of herpes zoster in adults aged ≥50 years. The vaccine consists of 2 doses (0.5 mL each), administered intramuscularly, 2-6 months apart (1). On October 25, 2017, the Advisory Committee on Immunization Practices (ACIP) recommended the recombinant zoster vaccine (RZV) for use in immunocompetent adults aged ≥50 years.

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.

The 5% Lidocaine-Medicated Plaster: Its Inclusion in International Treatment Guidelines for Treating Localized Neuropathic Pain, and Clinical Evidence Supporting its Use

When peripheral neuropathic pain affects a specific, clearly demarcated area of the body, it may be described as localized neuropathic pain (LNP). Examples include postherpetic neuralgia and painful diabetic neuropathy, as well as post-surgical and post-traumatic pain. These conditions may respond to topical treatment, i.e., pharmaceutical agents acting locally on the peripheral nervous system, and the topical route offers advantages over systemic administration. Notably, only a small fraction of the dose reaches the systemic circulation, thereby reducing the risk of systemic adverse effects, drug–drug interactions and overdose. From the patient’s perspective, the analgesic agent is easily applied to the most painful area(s). The 5% lidocaine-medicated plaster has been used for several years to treat LNP and is registered in approximately 50 countries. Many clinical guidelines recommend this treatment modality as a first-line option for treating LNP, particularly in frail and/or elderly patients and those receiving multiple medications, because the benefit-to-risk ratios are far better than those of systemic analgesics. However, some guidelines make only a weak recommendation for its use. This paper considers the positioning of the 5% lidocaine-medicated plaster in international treatment guidelines and how they may be influenced by the specific criteria used in developing them, such as the methodology employed by randomized, placebo-controlled trials. It then examines the body of evidence supporting use of the plaster in some prevalent LNP conditions. Common themes that emerge from clinical studies are: (1) the excellent tolerability and safety of the plaster, which can increase patients’ adherence to treatment, (2) continued efficacy over long-term treatment, and (3) significant reduction in the size of the painful area. On this basis, it is felt that the 5% lidocaine-medicated plaster should be more strongly recommended for treating LNP, either as one component of a multimodal approach or as monotherapy.

Efficacy of the Herpes Zoster Subunit Vaccine in Adults 70 Years of Age or Older

BACKGROUND

A trial involving adults 50 years of age or older (ZOE-50) showed that the herpes zoster subunit vaccine (HZ/su) containing recombinant varicella-zoster virus glycoprotein E and the AS01B adjuvant system was associated with a risk of herpes zoster that was 97.2% lower than that associated with placebo. A second trial was performed concurrently at the same sites and examined the safety and efficacy of HZ/su in adults 70 years of age or older (ZOE-70).

METHODS

This randomized, placebo-controlled, phase 3 trial was conducted in 18 countries and involved adults 70 years of age or older. Participants received two doses of HZ/su or placebo (assigned in a 1:1 ratio) administered intramuscularly 2 months apart. Vaccine efficacy against herpes zoster and postherpetic neuralgia was assessed in participants from ZOE-70 and in participants pooled from ZOE-70 and ZOE-50.

RESULTS

In ZOE-70, 13,900 participants who could be evaluated (mean age, 75.6 years) received either HZ/su (6950 participants) or placebo (6950 participants). During a mean follow-up period of 3.7 years, herpes zoster occurred in 23 HZ/su recipients and in 223 placebo recipients (0.9 vs. 9.2 per 1000 person-years). Vaccine efficacy against herpes zoster was 89.8% (95% confidence interval [CI], 84.2 to 93.7; P<0.001) and was similar in participants 70 to 79 years of age (90.0%) and participants 80 years of age or older (89.1%). In pooled analyses of data from participants 70 years of age or older in ZOE-50 and ZOE-70 (16,596 participants), vaccine efficacy against herpes zoster was 91.3% (95% CI, 86.8 to 94.5; P<0.001), and vaccine efficacy against postherpetic neuralgia was 88.8% (95% CI, 68.7 to 97.1; P<0.001). Solicited reports of injection-site and systemic reactions within 7 days after injection were more frequent among HZ/su recipients than among placebo recipients (79.0% vs. 29.5%). Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two study groups.

CONCLUSIONS

In our trial, HZ/su was found to reduce the risks of herpes zoster and postherpetic neuralgia among adults 70 years of age or older. (Funded by GlaxoSmithKline Biologicals; ZOE-50 and ZOE-70 ClinicalTrials.gov numbers, NCT01165177 and NCT01165229 .).

The use of Zostavax in Spain: the economic case for vaccination of individuals aged 50 years and older

Background Population aging brings up a number of health issues, one of which is an increased incidence of herpes zoster (HZ) and its complication, post-herpetic neuralgia (PHN). Zostavax vaccine has recently become available to prevent HZ and PHN. This study evaluates the cost-effectiveness of vaccination against HZ in Spain considering a vaccination of the population aged 50 years and older and comparing this to the current situation where no vaccination is being administered. Methods An existing, validated, and published economic model was adapted to Spain using relevant local input parameters and costs from 2013. Results Vaccinating 30% of the Spanish population aged 50 years and older resulted in €16,577/QALY gained, €2025/HZ case avoided, and €5594/PHN case avoided under the third-party payer perspective. From a societal perspective, the ICERs increased by 6%, due to the higher price of the vaccine. The number needed to vaccinate to prevent one case was 20 for HZ, and 63 for PHN3. Sensitivity analyses showed that the model was most sensitive to the HZ and PHN epidemiological data, the health state utilities values, and vaccine price used. Conclusion Considering an acceptable range of cost-effectiveness of €30,000-€50,000 per QALY gained, vaccination of the 50+ population in Spain against HZ with a new vaccine, Zostavax, is cost-effective and makes good use of the valuable healthcare budget.

Impact of Data Imputation Methodology on Pain Assessment over 24 Hours in a Randomized, Placebo-Controlled Study of Gabapentin Enacarbil in Patients with Neuropathic Pain Associated with Postherpetic Neuralgia

OBJECTIVE

To assess the impact of gabapentin enacarbil on primary and secondary pain endpoints using three data imputation methodologies in a randomized phase II study of adult patients with postherpetic neuralgia.

METHODS

The primary endpoint was change from baseline to end of maintenance treatment in mean 24-hour average pain intensity score. Secondary endpoints (daytime/nighttime average pain intensity score, daytime/nighttime current pain intensity score, and daytime/nighttime worst pain intensity score) were based on daily electronic diary assessments. Comparisons of each gabapentin enacarbil dose with placebo were performed using three different statistical methodologies: last observation carried forward, baseline observation carried forward, and mixed-effect model for repeated measures.

RESULTS

Of the 376 randomized patients, 371 were in the intent-to-treat population (gabapentin enacarbil 1,200 mg, 107; 2,400 mg, 82; 3,600 mg, 87; placebo, 95). For mean 24-hour average pain intensity score, there were statistically significant improvements from baseline to end of maintenance treatment for all gabapentin enacarbil groups vs placebo using the three analysis methods. Significant improvements were also observed for all secondary endpoints with gabapentin enacarbil 1,200 mg using the three analysis methods. Most secondary endpoints also showed improvements following treatment with gabapentin enacarbil 2,400 mg or 3,600 mg compared with placebo.

CONCLUSIONS

Gabapentin enacarbil (1,200 mg, 2,400 mg, and 3,600 mg) was effective and well tolerated in patients with postherpetic neuralgia compared with placebo, as confirmed by three different and robust statistical methodologies.

5% Lidocaine Medicated Plaster for the Treatment of Postherpetic Neuralgia: A Review of the Clinical Safety and Tolerability

Postherpetic neuralgia (PHN) is a common, very painful, and often long-lasting complication of herpes zoster which is frequently underdiagnosed and undertreated. It mainly affects the elderly, many of whom are already treated for comorbidities with a variety of systemic medications and are thus at high risk of drug-drug interactions. An efficacious and safe treatment with a low interaction potential is therefore of high importance. This review focuses on the safety and tolerability of the 5% lidocaine medicated plaster, a topical analgesic indicated for the treatment of PHN. The available literature (up to June 2014) was searched for publications containing safety data regarding the use of the 5% lidocaine medicated plaster in PHN treatment; unpublished clinical safety data were also included in this review. The 5% lidocaine medicated plaster demonstrated good short- and long-term tolerability with low systemic uptake (3 ± 2%) and minimal risk for systemic adverse drug reactions (ADRs). ADRs related to topical lidocaine treatment were mainly application site reactions of mild to moderate intensity. The treatment discontinuation rate was generally below 5% of patients. In one trial, the 5% lidocaine medicated plaster was better tolerated than systemic treatment with pregabalin. The 5% lidocaine medicated plaster provides a safe alternative to systemic medications for PHN treatment, including long-term pain treatment.

Mindfulness meditation in older adults with postherpetic neuralgia: a randomized controlled pilot study

This parallel-group, randomized controlled pilot study examined daily meditation in a diverse sample of older adults with postherpetic neuralgia. Block randomization was used to allocate participants to a treatment group (n = 13) or control group (n = 14). In addition to usual care, the treatment group practiced daily meditation for six weeks. All participants completed questionnaires at enrollment in the study, two weeks later, and six weeks after that, at the study's end. Participants recorded daily pain and fatigue levels in a diary, and treatment participants also noted meditation practice. Results at the 0.10 level indicated improvement in neuropathic, affective, and total pain scores for the treatment group, whereas affective pain worsened for the control group. Participants were able to adhere to the daily diary and meditation requirements in this feasibility pilot study.

Preventing and managing herpes zoster: key actions to foster healthy aging

Population aging is the demographic phenomenon characterizing all countries in the world, and it is challenging the national infrastructures, in particular health systems. However, aging itself is not associated with increased medical spending, but disability and comorbidity that affect older individuals are the actual drivers for health expenditures. Therefore, if people age in better health, medical spending may be significantly reduced. Preventative interventions proved to be effective in reducing/preventing disease and disability and often found to be cost effective, include diet and exercise interventions, medications, routine disease screenings, and immunizations. Vaccination can protect older citizens against life-threatening diseases, such as influenza, pneumococcal infections, tetanus, and against diseases which adversely impact their quality of life, such as herpes zoster (HZ). Including HZ vaccination in its citizens' lifetime immunization calendar can reinforce Europe's commitment toward active, healthy aging. This paper outlines the consensus statement of a group of Italian experts on HZ.

Reducing the burden of Herpes Zoster in Italy

Herpes Zoster (HZ) is a viral disease with painful neuro-dermatologic manifestations. Incidence increases with age. In Italy, the estimated incidence is 6.3 cases/1000 person/year; hospital admissions are less than 2%, 69% in patients aged over 65 years. The most frequent complication of HZ is Post-Herpetic Neuralgia (PHN) characterized by metameric pain, allodynia, and hyperalgesia. In Italy 20.6% and 9.2% of HZ patients experience PHN after 3 and 6 months, respectively. Available antiviral and analgesic treatments are relatively unsatisfactory in reducing pain and length of the disease. Prevention has recently become possible with the live attenuated vaccine Oka/Merck. Clinical studies show a reduction of 51% in the incidence of the disease, 61% of its burden and 67% of PHN in vaccinees. Protection seems to be long lasting and vaccine safety matches registration requirements. Available evidence suggests that the costs for QALY (less than € 20 000) and avoided cases is favorable. Due to the heavy burden of disease, it is time to offer this vaccination to elderly population.

Herpes zoster surveillance using electronic databases in the Valencian Community (Spain)

BACKGROUND

Epidemiologic data of Herpes Zoster (HZ) disease in Spain are scarce. The objective of this study was to assess the epidemiology of HZ in the Valencian Community (Spain), using outpatient and hospital electronic health databases.

METHODS

Data from 2007 to 2010 was collected from computerized health databases of a population of around 5 million inhabitants. Diagnoses were recorded by physicians using the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM). A sample of medical records under different criteria was reviewed by a general practitioner, to assess the reliability of codification.

RESULTS

The average annual incidence of HZ was 4.60 per 1000 persons-year (PY) for all ages (95% CI: 4.57-4.63), is more frequent in women [5.32/1000PY (95% CI: 5.28-5.37)] and is strongly age-related, with a peak incidence at 70-79 years. A total of 7.16/1000 cases of HZ required hospitalization.

CONCLUSIONS

Electronic health database used in the Valencian Community is a reliable electronic surveillance tool for HZ disease and will be useful to define trends in disease burden before and after HZ vaccine introduction.

Predictive factors for postherpetic neuralgia using ordered logistic regression analysis

OBJECTIVES

To identify predictive factors for the occurrence of postherpetic neuralgia (PHN).

METHODS

The participants were 73 herpes zoster patients who had been treated at the pain clinic of our hospital between January 2008 and June 2010. Variables present at the initial visit were extracted from the clinical records for regression analysis of factors related to the occurrence of PHN. The following scores for response were used: 0=no PHN after 3 months; 1=PHN present after 3 months but absent after 6 months; and 2=PHN present after 6 months. Multivariate ordered logistic regression analysis was performed to identify the predictive factors for PHN.

RESULTS

Advanced age [odds ratio (OR)=2.740, confidence interval (CI)=1.110-6.761; P=0.0288] and deep pain (OR=4.244, CI=1.114-16.163; P=0.0341) at the initial visit to our outpatient pain clinic were found to be significant predictive factors for the occurrence of PHN. Diabetes mellitus (OR=3.075) and pain reduced by bathing (OR=3.389) also had high OR, although they were not significant.

DISCUSSION

Our study indicates that advanced age and deep pain at the initial visit are significant predictors for PHN. Our results are considered likely to contribute to the establishment of evidence-based medicine in the optimal treatment of PHN.

Influence of anatomic location of lidocaine patch 5% on effectiveness and tolerability for postherpetic neuralgia

PURPOSE

Lidocaine patch 5% is recommended as a first-line therapy for postherpetic neuralgia pain in neuropathic pain guidelines. Postherpetic neuralgia can occur anywhere on the body but often follows acute herpes zoster occurring in trigeminal and brachial plexus dermatomes. An analysis was conducted to determine whether the anatomic location of lidocaine patch 5% is associated with variations in effectiveness or tolerability in patients with postherpetic neuralgia.

METHODS

This was a post hoc analysis by anatomic site of patch placement (head [including neck], trunk [chest, abdomen, back, hips], and extremities [arm, leg]) of a 4-week, multicenter, open-label study that enrolled patients with persistent pain following herpes zoster infection. Effectiveness was measured by Brief Pain Inventory (BPI) average pain intensity (0 [no pain] to 10 [worst imaginable pain]) and the BPI subscale for pain relief (0% [no relief] to 100% [complete relief]). Tolerability was assessed on the basis of patient-reported adverse events.

RESULTS

Of 332 enrolled patients (59.6% women [n = 198]; 92.5% white [n = 307]; mean [standard deviation] age, 71.2 [13.9] years), those (n = 203) who applied lidocaine patch 5% to a single anatomic site only and had baseline and postbaseline pain score data were analyzed (trunk, n = 130; head, n = 41; extremities, n = 32). The frequency of adverse events differed significantly by anatomic location, with significantly more adverse events reported with patch placement on the head versus the extremities (P = 0.006) or trunk (P = 0.02). BPI average pain improved significantly from baseline in each of the three anatomic areas (mean score decrease, 1.50-2.04; P ≤ 0.002), with no significant difference in effectiveness by patch location.

CONCLUSION

Lidocaine 5% patch was effective and generally well tolerated for each anatomic area evaluated, although application to the head was tolerated less well compared with the trunk and extremities.

Advances in the treatment of varicella-zoster virus infections

Varicella-zoster virus (VZV) causes two distinct diseases, varicella (chickenpox) and shingles (herpes zoster). Chickenpox occurs subsequent to primary infection, while herpes zoster (usually associated with aging and immunosuppression) appears as a consequence of reactivation of latent virus. The major complication of shingles is postherpetic neuralgia. Vaccination strategies to prevent varicella or shingles and the current status of antivirals against VZV will be discussed in this chapter. Varivax®, a live-attenuated vaccine, is available for pediatric varicella. Zostavax® is used to boost VZV-specific cell-mediated immunity in adults older than 50 years, which results in a decrease in the burden of herpes zoster and pain related to postherpetic neuralgia. Regardless of the availability of a vaccine, new antiviral agents are necessary for treatment of VZV infections. Current drugs approved for therapy of VZV infections include nucleoside analogues that target the viral DNA polymerase and depend on the viral thymidine kinase for their activation. Novel anti-VZV drugs have recently been evaluated in clinical trials, including the bicyclic nucleoside analogue FV-100, the helicase-primase inhibitor ASP2151, and valomaciclovir (prodrug of the acyclic guanosine derivative H2G). Different candidate VZV drugs have been described in recent years. New anti-VZV drugs should be as safe as and more effective than current gold standards for the treatment of VZV, that is, acyclovir and its prodrug valacyclovir.

Safety and efficacy outcomes of long-term treatment up to 4 years with 5% lidocaine medicated plaster in patients with post-herpetic neuralgia

OBJECTIVE

Prospective evaluation of the long-term efficacy and safety of the 5% lidocaine medicated plaster in patients with post-herpetic neuralgia (PHN).

RESEARCH DESIGN AND METHODS

Patients with persisting pain for ≥3 months after acute herpes zoster and a baseline pain intensity of at least 4 on an 11-point numerical rating scale (NRS 0-10) were treated with 5% lidocaine medicated plasters for up to 5 years and monitored in regular intervals. Efficacy parameters are presented for the first 4 years and include patients' recall of pain relief (6-point verbal rating scale (VRS), clinical global impression of change (CGIC), patients' global impression of change PGIC), and the global evaluations of study medication. Safety parameters (clinical examination, skin evaluation, laboratory) and adverse events (AEs) were assessed at regular visits.

CLINICAL TRIAL REGISTRATION

KF10004/02.

RESULTS

A total of 102 patients continuing from a 1 year main study period were included in an extension phase of up to 3 years. Ten patients (9.8%) dropped out due to lack of efficacy and 9 patients (8.8%) due to treatment-related AEs; 56 patients (54.9%) left the study for non-treatment-related reasons. Twenty-seven patients (26.4%) were still under treatment after a total treatment period of 4 years. On average, a pain relief of at least 4.3 (between moderate and a lot) was achieved throughout the study. At all visits the CGIC and the PGIC were much or very much improved in about 80% of patients. At the final visit, study medication was rated at least to be good by 91% of physicians and 89% of patients. Drug-related adverse events (DRAEs) were reported in 19 of 102 patients, mainly mild to moderate localized skin reactions. There were no hints for a reduced analgesic effect or an increase of DRAEs with long-term treatment.

CONCLUSIONS

This study demonstrates that long-term treatment of ≥12 months with the 5% lidocaine medicated plaster is effective and well tolerated in PHN patients. These findings support the recommendations to use the 5% lidocaine medicated plaster as baseline therapy for localized neuropathic pain after herpes zoster infection (PHN).

CYP2D6*4 polymorphism, tramadol treatment and its clinical impact in patients with postherpetic neuralgia

Aim: The aim of this study was to investigate the associations between the CYP2D6*4 polymorphism, interindividual differences in CYP2D6 activity and adverse drug effects in postherpetic neuralgia (PHN) patients receiving tramadol. Patients & methods: The study comprised 158 patients (including 78 nonresponders and 80 responders) with PHN who were undergoing analgesic treatment at the Pain Clinic in the Out Patient Department of the University College of Medical Sciences, Guru Teg Bahadur Hospital (New Delhi, India). The numerical rating scale scores were measured at the resting and movement stages; Neuropathic Pain Symptom Inventory scores were evaluated by the treating physician. WHO-brief questionnaire scores for quality of life and adverse drug effects during the time of study were recorded. All samples were analyzed for the CYP2D6*4 polymorphism using the PCR-restriction fragmentation length polymorphism method. Results: The genotype distribution did not vary significantly among different age groups in nonresponders and responders. The CYP2D6*4 polymorphism was significantly associated with lower Neuropathic Pain Symptom Inventory (burning, squeezing stabbing and pressure) scores. The quality-of-life (sociological, psychological and environmental domains) scores correlated with CYP2D6*4 and showed significant results (p < 0.05) using a generalized linear model. No association was found between the physiological domain compared with the CYP2D6*4 allele (p > 0.05). In addition, the homozygous mutated CYP2D6*4 allele was not related to adverse effects of analgesic therapy. Conclusion: The CYP2D6*4 polymorphism may not be a predictor for treatment outcome of patients with PHN receiving tramadol. However, further investigation is required to confirm these findings in a larger sample size.

5% lidocaine medicated plaster in elderly patients with postherpetic neuralgia: results of a compassionate use programme in France

BACKGROUND

Postherpetic neuralgia (PHN) is a common, debilitating complication of herpes zoster that has a major impact on patients' quality of life. PHN prevalence increases with advancing age. One treatment option is the topical analgesic 5% lidocaine (lignocaine) medicated plaster (Versatis®), which has been proven to be efficacious and well tolerated in a number of randomized clinical studies.

OBJECTIVE

The aim of this analysis was to assess the use of the lidocaine medicated plaster under clinical practice conditions in a patient population whose previous PHN treatment with antidepressant and/or antiepileptic agents was inadequate or was not tolerated, or for whom such treatment was contraindicated or not recommended.

METHODS

This was a prospective, multicentre, non-interventional observation conducted in private and public health centres in France under a compassionate use programme (CUP). To obtain this new - and, at the time, unauthorized - PHN treatment alternative, physicians (in accordance with French guidelines) had to complete standardized case report forms for each patient before his/her inclusion in the CUP. As it was a CUP and therefore a non-interventional observation, returning documented information on follow-up visits to the medication provider was voluntary, and only a limited number of physicians returned completed forms. Documentation was, however, mandatory for adverse events (AEs) occurrence. Depending on the size of the painful skin area, up to three lidocaine plasters daily were applied for a maximum of 12 hours with plaster-free intervals of at least 12 hours. The study assessed changes in the prescription of concomitant PHN medication from the start of lidocaine plaster treatment to the last follow-up visit, both in terms of the sum of all concomitant PHN treatments and stratified by type of treatment: antiepileptic drugs, tricyclic antidepressants (TCAs), serotonin reuptake inhibitors (SRIs), classical analgesics (classified as step 1, 2 or 3 according to the WHO cancer pain ladder), transcutaneous electrical nerve stimulation, and others (mainly NSAIDs). AEs were monitored for safety.

RESULTS

A total of 625 patients were included in the CUP and permitted to receive lidocaine plaster treatment. Physicians returned 273 documented follow-up visit report forms. The mean ± SD CUP duration (i.e. duration of lidocaine plaster treatment) was 2.4 ± 2.5 months (median 1 month). Efficacy was assessed in the group of patients with documented follow-up visits (n = 273; mean ± SD age 73.6 ± 11.2 years), of whom 184 were aged ≥70 years (elderly efficacy population). The safety analysis included 625 patients (mean ± SD age 73.2 ± 11.9 years). Lidocaine plaster treatment resulted in a significant mean reduction of one concomitant PHN treatment per patient in the overall efficacy population analysed at the end of the observation (p < 0.001). In both populations (overall efficacy and elderly efficacy population), significantly fewer patients received TCAs (p = 0.003 and p = 0.001, respectively), step 3 analgesics (p = 0.001 and p = 0.005, respectively), and other miscellaneous treatments (p < 0.001 for both populations); there was also a significant reduction in the proportion of patients who took step 2 analgesics (p = 0.009) in the overall efficacy group. AEs (mainly related to local plaster application) were documented for 2.6% of the patients in the safety population; none were considered serious.

CONCLUSIONS

In day-to-day clinical practice management of PHN, treatment with the 5% lidocaine medicated plaster permitted a significant quantitative reduction in concomitant treatments for neuropathic pain in the overall efficacy population. In the subgroup aged ≥70 years, the quantitative reduction was non-significant. However, in both populations, 5% lidocaine medicated plaster reduced use of TCAs and step 3 analgesics. An improved polymedication status and good tolerability in this likely multimorbid age group indicate that the plaster is a new therapeutic alternative for patients suffering from PHN in France.

Emerging drugs for varicella-zoster virus infections

INTRODUCTION

Varicella-zoster virus (VZV) is the etiological agent of two distinct diseases, varicella (chickenpox) and shingles (herpes zoster). Chickenpox occurs following primary infection, while herpes zoster (usually associated with ageing and immunosuppression) is the consequence of reactivation of the latent virus. Post-herpetic neuralgia is the major complication of shingles.

AREAS COVERED

This review will discuss vaccination strategies and the current status of antivirals against VZV. A live attenuated vaccine, Varivax, is available for pediatric varicella while Zostavax was developed to boost VZV-specific cell-mediated immunity in adults older than 60 years and, via this mechanism, to decrease the burden of herpes zoster and pain associated with post-herpetic neuralgia. Despite the availability of a vaccine, there is a need for new antiviral agents. Current drugs approved for the treatment of VZV infections include nucleoside analogs that target the viral DNA polymerase and depend on the viral thymidine kinase. Novel anti-VZV drugs have recently been evaluated in clinical trials, including the bicyclic nucleoside analog FV-100, the helicase-primase inhibitor ASP2151 and valomaciclovir (prodrug of the acyclic guanosine derivative H2G).

EXPERT OPINION

New anti-VZV drugs should be as safe as and more effective than acyclovir and its prodrug valacyclovir (current gold standard for the treatment of VZV).

[Burden of herpes zoster and postherpetic neuralgia: Incidence, proportion, and associated costs in the French population aged 50 or over]

BACKGROUND

Despite the perspective of vaccination against herpes zoster, there are few recent data available on the incidence of this disease, the proportion of postherpetic neuralgia cases, and associated disease management costs. This study was performed to evaluate these parameters in a representative sample of French physicians.

METHODS

It was a retrospective, declarative study conducted from the medical files of patients who presented with herpes zoster and consulted in 2005, based on a random sample of GPs, dermatologists, neurologists, and physicians in pain clinics, weighted by demographic departmental distribution of patients aged 50 years and above. The analysis was performed on cases diagnosed by physicians themselves (incident cases).

RESULTS

The annual incidence of herpes zoster was estimated at 8.99/1000 [8.34-9.64], all types of physicians pooled and at 8.67/1000 for GPs. This represents about 182,500 cases of herpes zoster in France in 2005 in patients aged 50 years and above. Incidence was slightly higher amongst women (1.3 times) and increased with age. Amongst the 777 cases of incident herpes zoster, 343 were complicated by postherpetic neuralgia one month after diagnosis. The proportion of patients presenting postherpetic neuralgia at 3 and 6 months was 32.1% and 17.6%, respectively. The annual cost of management of herpes zoster and postherpetic neuralgia was estimated at 170 [109-249] million euros, of which 61.0 million euros were covered by the national health insurance.

CONCLUSION

In this study, the incidence of herpes zoster observed in France in subjects aged 50 years and above is close to that already estimated in France and Europe. The proportion of postherpetic neuralgia is high and this painful complication may persist for several months after diagnosis of herpes zoster. To our knowledge, EPIZOD is the first study conducted in France to assess the cost of herpes zoster and of postherpetic neuralgia, the most frequent complication of this viral disease.

An audit on assessment and management of pain at the time of acute hospital admission in older people

BACKGROUND

Pain management is fundamental to good clinical care. All patients who are admitted into hospital with any acute condition should be assessed about the presence or absence of pain and managed appropriately at the time of admission. As the prevalence of pain is high in older people, we examined how well it is assessed and managed in the older people in a typical medical emergency setting in the UK.

METHODS

We performed a retrospective audit in a district general hospital with catchment population of 250,000 in West Norfolk, UK. We included all patients admitted to care of the elderly wards during October-November 2007. We evaluated management of pain within the first 24 h of acute hospital admission.

RESULTS

Of the 140 patients admitted, 74 (53%) were male and their median age was 84 years (range = 56-99; = < 70, n = 8). Only 93 (66%) were asked about the presence or absence of pain on admission. Of those who complained of pain (n = 45), severity of pain was documented in 5 (11%) and the management was documented in 17 (38%). Of 17 with documented pain management, only 4 (23%) had further assessment of effectiveness of pain management. Only 70 (50%) of the patients had their mental state assessed by the abbreviated mental test score (AMTS). Among those who complained of pain and AMTS < or = 8 (n = 51), only 4 (8%) had objective documentation.

CONCLUSIONS

Our findings suggest that pain management may be sub-optimal in older people in the acute medical settings. Regular monitoring and education may have potential to improve assessment and management of pain in these vulnerable older adults.

The impact of herpes zoster and post-herpetic neuralgia on quality-of-life

BACKGROUND

The potentially serious nature of herpes zoster (HZ) and the long-term complication post-herpetic neuralgia (PHN) are often underestimated. One in four people will contract herpes zoster in their lifetime, with this risk rising markedly after the age of 50 years, and affecting one in two in elderly individuals. Pain is the predominant symptom in all phases of HZ disease, being reported by up to 90% of patients. In the acute phase, pain is usually moderate or severe, with patients ranking HZ pain as more intense than post-surgical or labour pains. Up to 20% of patients with HZ develop PHN, which is moderate-to-severe chronic pain persisting for months or years after the acute phase. We review the available data on the effect of HZ and PHN on patients' quality-of-life.

DISCUSSION

Findings show that HZ, and particularly PHN, have a major impact on patients' lives across all four health domains--physical, psychological, functional and social. There is a clear correlation between increasing severity of pain and greater interference with daily activities. Non-pain complications such as HZ ophthalmicus can increase the risk of permanent physical impairment. Some elderly individuals may experience a permanent loss of independence after an acute episode of HZ. Current challenges in the management of HZ and PHN are highlighted, including the difficulty in administering antiviral agents before pain becomes established and the limited efficacy of pain treatments in many patients. We discuss the clinical rationale for the HZ vaccine and evidence demonstrating that the vaccine reduces the burden of the disease. The Shingles Prevention Study, conducted among >38,000 people aged >or=60 years old, showed that the HZ vaccine significantly reduces the burden of illness and the incidence of both HZ and PHN. In the entire study population, zoster vaccination reduced the severity of interference of HZ and PHN with activities of daily living by two-thirds, as measured by two questionnaires specific to HZ.

SUMMARY

A vaccination scheme may positively impact the incidence and course of HZ disease, thereby improving patients' quality-of-life.

Impact of herpes zoster and post-herpetic neuralgia on patients' quality of life: a patient-reported outcomes survey

BACKGROUND: The impact of herpes zoster (HZ) and post-herpetic neuralgia (PHN) on patients' quality of life (QoL) is currently poorly documented. SUBJECTS AND METHODS: Telephone interviews in Germany identified patients ≥50 years old with painful HZ diagnosed during the previous 5 years. Bespoke questions evaluated previous HZ episodes. RESULTS: Of 11,009 respondents, 280 met the screening criteria, and 32 (11%) developed PHN. PHN was associated with significantly worse outcomes than HZ (all P < 0.05). Mean pain scores associated with PHN and HZ, respectively, were 7.1 and 6.2 (average) and 8.2 and 7.0 (worst). Many patients with PHN (91%) and HZ (73%) experienced problems with daily activities, including work, studies, housework, family and leisure activities. Mean pain interference scores in patients with PHN versus HZ were highest for sleep (6.5 versus 4.9), normal work (6.1 versus 4.4) and mood (5.9 versus 4.4). Most employed interviewees with PHN (70%) and HZ (64%) stopped work during the disease. Pain and QoL outcomes were not significantly different between all patients versus those diagnosed during the previous 12 months or between patients aged 50-59 years versus ≥60 years. CONCLUSIONS: HZ causes substantial pain, which seriously interferes with many aspects of daily life, particularly in patients with PHN.