Antiepileptics for post-herpetic neuralgia in the elderly: current and future prospects

Pain Management in the Older Adults: A Narrative Review

With the increase in life expectancy in the United States, octogenarians and nonagenarians are more frequently seen in clinical practice. The older adults patients have multiple preexisting comorbidities and are on multiple medications, which can make pain management complex. Moreover, the older adults population often suffers from chronic pain related to degenerative processes, making medical management challenging. In this review, the authors collated available evidence for best practices for pain management in the older adults.

Pharmacological Pain Treatment in Older Persons

Pharmacological pain treatment in older persons is presented by a multi-disciplinary group of European pain experts. Drugs recommended for acute or chronic nociceptive pain, also for neuropathic pain and the routes of administration of choice are the same as those prescribed for younger persons but comorbidities and polypharmacy in older persons increase the risk of adverse effects and drug interactions. Not all drugs are available or authorised in all European countries. For mild-to-moderate pain, non-opioids including paracetamol and non-steroidal anti-inflammatory drugs are first-line treatments, followed by nefopam and metamizole. Codeine, dihydrocodeine and tramadol are prescribed for moderate to severe pain and 'strong' opioids, including morphine, hydromorphone, oxycodone, fentanyl, buprenorphine, methadone and tapentadol, for severe pain. Chronic neuropathic pain treatment relies on coanalgesics, including anti-epileptics (gabapentinoids) and anti-depressants with additional option of topical lidocaine and capsaicine. The choice of analgesic(s) and the route of administration should be guided by the pain characteristics, as well as by the patient's comorbidities, organ function and medications. Several directions have been highlighted to optimise pharmacological pain management in older individuals: (1) before starting pain treatment adequately detect and assess pain and always perform a full geriatric assessment, (2) consider kidney function systematically to adjust the doses of analgesics and avoid the risks of overdose, (3) start with the lowest dose of an analgesic and increase it gradually under the control of the effect, (4) involve the older persons and family in their treatment, (5) reevaluate pain regularly during treatment and (6) combine pharmacological treatment with non-pharmacological approaches.

Pain Management in the Elderly: A Narrative Review

With the increase in life expectancy in the United States, octogenarians and nonagenarians are more frequently seen in clinical practice. The elderly patients have multiple preexisting comorbidities and are on multiple medications, which can make pain management complex. Moreover, the elderly population often suffers from chronic pain related to degenerative processes, making medical management challenging. In this review, the authors collated available evidence for best practices for pain management in the elderly.

Trends in gabapentinoid prescribing in UK primary care using the Clinical Practice Research Datalink: an observational study

Background

The UK government reclassified gabapentin and pregabalin as 'controlled drugs' from April 2019. This study aimed to describe the trends in gabapentinoid prescribing before and immediately after reclassification, in the UK Clinical Practice Research Datalink, an electronic primary care health record broadly representative of the UK.

Methods

Separately for gabapentin and pregabalin, we calculated annual incident and prevalent prescribing rates from year of UK approval (April 1997 and 2004 respectively) to September 2019, and monthly incident and prevalent prescribing rates (October 2017-September 2019). Significant changes in temporal trends were determined using joinpoint regression. We also described potential prescribing indications, prior pain-related prescribing, and co-prescribing with potentially interacting medicines.

Findings

Incident gabapentin prescribing increased annually, peaking in 2016-17, at 625/100,000 patient years before falling steadily to 2019. Incident pregabalin prescribing peaked at 329/100,000 patient years in 2017-18 and did not fall significantly until 2019. Prevalent gabapentin and pregabalin prescribing increased annually to 2017-18 and 2018-19 respectively, before plateauing. Gabapentinoids were commonly co-prescribed with opioids (60%), antidepressants (52%), benzodiazepines (19%), and Z-drugs (10%).

Interpretation

Following a dramatic rise, incident gabapentinoid prescribing has started to fall but the specific impact of reclassification on prescribing rates remains unclear. Limited change in prevalent gabapentinoid prescribing during the 6 months following their reclassification as controlled drugs suggests little immediate impact on continued gabapentinoid prescribing for existing users.

Funding

National Institute for Health and Care Research (NIHR) Research for Patient Benefit Programme. NIHR Applied Research Collaboration West Midlands. NIHR School for Primary Care Research.

Topical Lidocaine for Chronic Pain Treatment

Topical lidocaine is widely used in current practice for a variety of pain conditions. This literature review shows that its limited absorption and relative lack of systemic adverse events are an attractive analgesic option for a number of vulnerable patients. Topical lidocaine has been approved by health authorities for the treatment of post-herpetic neuralgia in a number of countries, and studies present some degree of evidence of its efficacy and safety in postsurgical pain, diabetic peripheral neuropathy, carpal tunnel syndrome, chronic lower back pain and osteoarthritis. Topical lidocaine may be a great alternative alone or in addition to systemic drugs and non-pharmacological approaches for an optimized pain management and in multimodal analgesia.

Dorsal root ganglion stimulation for refractory post-herpetic neuralgia

Post-herpetic neuralgia is a chronic neuropathic pain disorder that is the sequela of the varicella zoster virus reactivation in the dorsal root ganglion. A variety of treatment modalities have been implemented, but pharmacologic treatments are often limited due to side effects and interventional procedures have yielded mixed results without promising long-term benefits being consistently seen. A dorsal root ganglion stimulator for treatment of post-herpetic neuralgia is a novel treatment option as it is able to specifically target the area affected. We present 3 patients who underwent implantation of permanent dorsal root ganglion stimulators and had a greater than 50% decrease in scoring on numerical rating scale (NRS) up to 18 months post-procedure and significantly reduced analgesic requirements.

Managing Pain in the Older Cancer Patient

PURPOSE OF REVIEW

This paper aims to give the specialist and non-specialist alike an overview of the considerations involved in the management of cancer-related pain in the older population.

RECENT FINDINGS

Comprehensive guidelines on cancer pain management have been published recently by expert bodies. Cancer pain differs in many respects to other pain conditions and we are likely to encounter it more frequently in older patients in the future. The elderly are more sensitive to the effects of many analgesic medications. The elderly patient with cancer pain presents a unique challenge to the treating physician. The biological effects of ageing impact on the efficacy of many pain management strategies as well as its diagnosis and assessment. Treatment options can be broadly divided into pharmacological, non-pharmacological and interventional. A multidisciplinary approach and frequent re-assessment are essential in achieving favourable outcomes in this patient group.

Pain therapy for the elderly patient: is opioid-free an option?

PURPOSE OF REVIEW

Chronic noncancer pain is an increasing problem in elderly because of rising life expectancy together with an increase of potentially painful medical conditions. Concomitantly, adequate treatment of elderly is often limited by coexisting diseases and polypharmacy.This review summarizes the most important specifics presented by elderly patients and discusses the pharmacological and nonpharmacological options of pain management.

RECENT FINDINGS

A comprehensive pain assessment is a prerequisite for effective pain management. However, this can be a major challenge in patients who are unable to communicate adequately, that is, in patients with dementia. A recently developed electronic tool assessing automated facial expression and clinical behavioral indicators may help to solve this problem. The discussion about benefits and harms of opioids in elderly goes on. Although some authors underline the lack of efficacy together with the potential problems, such as, abuse, others report a beneficial effect in terms of pain relief, functional activities and disability. In addition, opioids have become an important treatment option in patients with restless legs syndrome. Various topical treatment options (i.e. capsaicin patch) and nonpharmacological interventions have been proven to be beneficial in elderly.

SUMMARY

Adequate pain management of elderly patients constitutes numerous pharmacological options including nonopioids, opioids, coanalgesics and topical agents. Due to age-related characteristics, all systemic analgesics have to be given very cautiously ('start low, go slow'). Whenever possible, treatment should be performed as a multimodal approach based on the biopsychosocial model of chronic pain.

Localized neuropathic pain: an expert consensus on local treatments

BACKGROUND

Pain localization is one of the hallmarks for the choice of first-line treatment in neuropathic pain. This literature review has been conducted to provide an overview of the current knowledge regarding the etiology and pathophysiology of localized neuropathic pain (LNP), its assessment and the existing topical pharmacological treatments.

MATERIALS AND METHODS

Literature review was performed using Medline from 2010 to December 2016, and all studies involving LNP and treatments were examined. A multidisciplinary expert panel of five pain specialists in this article reports a consensus on topical approaches that may be recommended to alleviate LNP and on their advantages in clinical practice.

RESULTS

Successive international recommendations have included topical 5% lidocaine and 8% capsaicin for LNP treatment. The expert panel considers that these compounds can be a first-line treatment for LNP, especially in elderly patients and patients with comorbidities and polypharmacy. Regulatory LNP indications should cover the whole range of LNP and not be restricted to specific etiologies or sites. Precautions for the use of plasters must be followed cautiously.

CONCLUSION

Although there is a real need for more randomized controlled trials for both drugs, publications clearly demonstrate excellent risk/benefit ratios, safety, tolerance and continued efficacy throughout long-term treatment. A major advantage of both plasters is that they have proven efficacy and may reduce the risk of adverse events such as cognitive impairment, confusion, somnolence, dizziness and constipation that are often associated with systemic neuropathic pain treatment and reduce the quality of life. Topical modalities also may be used in combination with other drugs and analgesics with limited drug-drug interactions.

Pain in the Elderly

Pain management in the elderly has increasingly become problematic in the USA as the aged population grows. The proportion of the population over 65 continues to climb and may eclipse 20 % in the next decade. In order to effectively diagnosis and treat these patients, a proper history and physical exam remain essential; pain assessment scales such as the Verbal Descriptor Scales (VDS), the Numerical Rating Scales (NRS), and the Visual Analogue Scales (VAS) often but not always prove beneficial. The conditions most frequently afflicting this population include osteoarthritis, diabetic neuropathy, post-herpetic neuralgia, and lower back pain which include spondylosis and radiculopathies. While the normal aging process does not necessarily guarantee symptoms of chronic pain, elderly individuals are far more likely to develop these painful conditions than their younger counterparts. There are many effective treatment modalities available as potential therapeutic interventions for elderly patients, including but not limited to analgesics such as NSAIDs and opioids, as well as multiple interventional pain techniques. This review will discuss chronic pain in the elderly population, including epidemiology, diagnostic tools, the multitude of co-morbidities, and common treatment modalities currently available to physicians.

An Algorithm for Neuropathic Pain Management in Older People

Neuropathic pain frequently affects older people, who generally also have several comorbidities. Elderly patients are often poly-medicated, which increases the risk of drug-drug interactions. These patients, especially those with cognitive problems, may also have restricted communication skills, making pain evaluation difficult and pain treatment challenging. Clinicians and other healthcare providers need a decisional algorithm to optimize the recognition and management of neuropathic pain. We present a decisional algorithm developed by a multidisciplinary group of experts, which focuses on pain assessment and therapeutic options for the management of neuropathic pain, particularly in the elderly. The algorithm involves four main steps: (1) detection, (2) evaluation, (3) treatment, and (4) re-evaluation. The detection of neuropathic pain is an essential step in ensuring successful management. The extent of the impact of the neuropathic pain is then assessed, generally with self-report scales, except in patients with communication difficulties who can be assessed using behavioral scales. The management of neuropathic pain frequently requires combination treatments, and recommended treatments should be prescribed with caution in these elderly patients, taking into consideration their comorbidities and potential drug-drug interactions and adverse events. This algorithm can be used in the management of neuropathic pain in the elderly to ensure timely and adequate treatment by a multidisciplinary team.

Neuropathic Pain due to Small Fiber Neuropathy in Aging: Current Management and Future Prospects

Over the last 10 years, the diagnosis small fiber neuropathy (SFN) has gained recognition worldwide. Patients often suffer from severe neuropathic pain that may be difficult to treat. A substantial subset of patients with SFN is aged 65 years or older, and these patients often exhibit comorbidities and usage of multiple drugs, making neuropathic pain treatment more challenging. In this review, we highlight relevant pathophysiological aspects and discuss currently used therapeutic strategies for neuropathic pain. Possible pitfalls in neuropathic pain treatment in the elderly will be underlined.

Is herpes zoster an additional complication in old age alongside comorbidity and multiple medications? Results of the post hoc analysis of the 12-month longitudinal prospective observational ARIZONA cohort study

OBJECTIVES

To examine the burden of comorbidity, polypharmacy and herpes zoster (HZ), an infectious disease, and its main complication post-herpetic neuralgia (PHN) in young (50-70 years of age: 70-) and old (≥ 70 years of age: 70+) patients.

DESIGN

Post hoc analysis of the results of the 12-month longitudinal prospective multicentre observational ARIZONA cohort study.

SETTINGS AND PARTICIPANTS

The study took place in primary care in France from 20 November 2006 to 12 September 2008. Overall, 644 general practitioners (GPs) collected data from 1358 patients aged 50 years or more with acute eruptive HZ.

OUTCOME MEASURES

Presence of HZ-related pain or PHN (pain persisting >3 months) was documented at day 0 and at months 3, 6, and 12. To investigate HZ and PHN burden, pain, quality of life (QoL) and mood were self-assessed using validated questionnaires (Zoster Brief Pain Inventory, 12-item Short-Form health survey and Hospital Anxiety and Depression Scale, respectively).

RESULTS

As compared with younger patients, older patients more frequently presented with comorbidities, more frequently took analgesics and had poorer response on all questionnaires, indicating greater burden, at inclusion. Analgesics were more frequently prescribed to relieve acute pain or PHN in 70+ than 70- patients. Despite higher levels of medication prescription, poorer pain relief and poorer response to all questionnaires were reported in 70+ than 70- patients.

CONCLUSIONS

Occurrence of HZ and progression to PHN adds extra burden on top of pharmacological treatment and impaired quality of life, especially in older patients who already have health problems to cope with in everyday life.

Functional decline and herpes zoster in older people: an interplay of multiple factors

Herpes zoster is a frequent painful infectious disease whose incidence and severity increase with age. In older people, there is a strong bidirectional link between herpes zoster and functional decline, which refers to a decrement in ability to perform activities of daily living due to ageing and disabilities. However, the exact nature of such link remains poorly established. Based on the opinion from a multidisciplinary group of experts, we here propose a new model to account for the interplay between infection, somatic/psychiatric comorbidity, coping skills, polypharmacy, and age, which may account for the functional decline related to herpes zoster in older patients. This model integrates the risk of decompensation of underlying disease; the risk of pain becoming chronic (e.g. postherpetic neuralgia); the risk of herpes zoster non-pain complications; the detrimental impact of herpes zoster on quality of life, functioning, and mood; the therapeutic difficulties due to multimorbidity, polypharmacy, and ageing; and the role of stressful life events in the infection itself and comorbid depression. This model underlines the importance of early treatment, strengthening coping, and vaccine prevention.