Amitriptyline effectively relieves neuropathic pain following treatment of breast cancer

Survey on recognition of post-mastectomy pain syndrome by breast specialist physician and present status of treatment in Japan

BACKGROUND

Post-mastectomy pain syndrome (PMPS) is chronic pain after breast cancer surgery and is reported to influence quality of life (QOL). Although the results of a survey in Japan showed high incidence, at 21-65 %, many of the patients had never been treated for PMPS. One reason for this low treatment rate may be poor understanding of PMPS by medical personnel. In this study, we conducted the survey by using questionnaire to assess current treatment and the recognitions of the medical personnel.

METHODS

We mailed a questionnaire to 647 specialist members of the Breast Cancer Society.

RESULTS

Of those, 34.7 % responsed. While PMPS was recognized by as much as 70.5 % of responding physicians, it was treated by as little as 47.7 % of the responders. In addition, while non-steroidal anti-inflammatory drugs (NSAIDs), which were ineffective in relieving PMPS, were used by 78.4 % of the responders, effective drugs were rarely used; therefore, treatment was considered ineffective by 69.5 %. This indicates that appropriate therapies are not widely used, and none of the current therapies are very effective.

CONCLUSIONS

The results showed high recognition of PMPS pathology among physicians, but the treatment rate was as low as 47.7 %. NSAIDs were the main treatment, and the treatment effects were not satisfactory. It was revealed that currently appropriate treatment modalities have not been widely used. Education of physicians, distribution of treatment information and further studies are considered necessary for the spread of appropriate treatment modality.

Adjuvant analgesics in cancer pain: a review

Adjuvant analgesics (co-analgesics) are medications whose primary indication is the management of a medical condition with secondary effects of analgesia. Cancer pain is multifactorial and often involves inflammatory, nociceptive, and neuropathic pain subtypes. Adjuvant analgesics used in conjunction with opioids have been found to be beneficial in the management of many cancer pain syndromes; however, they are currently underutilized. Antidepressants, anticonvulsants, local anesthetics, topical agents, steroids, bisphosphonates, and calcitonin are all adjuvants which have been shown to be effective in the management of cancer pain syndromes. When utilizing analgesic adjuvants in the treatment of cancer pain, providers must take into account the particular side effect profile of the medication. Ideally, adjuvant analgesics will be initiated at lower dosages and escalated as tolerated until efficacy or adverse effects are encountered.

Post-treatment surveillance in colorectal cancer

BACKGROUND

Though the post treatment surveillance of patients with colorectal cancer (CRC) treated with curative intent is common practice, its value is controversial. In the absence of conclusive clinical data, various modalities for the routine follow-up of patients with CRC have been proposed. In practice, the guidelines across countries and regions differ and are influenced by different health care policies, resource availability and doubts about effectiveness of follow-up.

CONCLUSIONS

The results of metaanalyses of available clinical trials demonstrated a survival benefit of intensified monitoring, but the questions regarding the optimal frequency of visits and the examinations to be performed remain unanswered. Furthermore, intensive monitoring of CRC survivors may be difficult to be administrated, causes discomfort and morbidity to the patient and can have serious cost-implications to the healthcare system. However, as it seems from available data, a comprehensive surveillance program does not affect the quality of patients' life. Ongoing large prospective multi-institutional randomised trials might elucidate some of the crucial questions and existing dilemmas to establish adequate surveillance strategy for CRC patients.

Pain management in epidermolysis bullosa

Pain is an unfortunate constant in the lives of most patients with epidermolysis bullosa (EB), especially for those with the more severe types of EB. Patients with EB have a broad spectrum of need for pain treatment, varying with the type of EB, the severity within that type, and the particular physical, emotional, and psychological milieu of each individual. Prevention of situations that precipitate trauma to the skin or exacerbate other pain-inducing complications of this multifaceted disorder is the primary goal of the treating physician. The approach to pain management is different in daily life, during intermittent exacerbations or injuries, or when hospitalizations or operative procedures occur.

Depression in cancer patients

Primary care clinicians who care for cancer patients are integral to the recognition, diagnosis, and management of depression in this population. A review of risk factors that may make patients more likely to develop depression can be a useful first step in screening for depression. Several screening instruments may guide clinicians in further work-up of patients suspected of being depressed. Depression is treatable in this patient population and prompt management may have a positive impact on overall outcomes. Pharmacologic and psychotherapeutic treatment options are numerous, and consideration of specific cancer treatments, including side-effect profiles, patient comorbidity, patient preference, and clinician resources, should direct management.

Use of lidocaine patches for neuropathic pain in a comprehensive cancer centre

BACKGROUND

There are few reports of the use of the lidocaine 5% patch (L5%P) for neuropathic pain (NP) in the cancer patient. Within a comprehensive cancer centre, L5%P has been prescribed by the Pain and Palliative Care Service (Peter McCallum Cancer Centre, East Melbourne, Victoria, Australia) for selected patients with NP since 2001.

OBJECTIVE

To retrospectively audit the use of L5%P within a comprehensive cancer centre.

METHODS

All L5%P prescriptions up to January 2009 were listed and patient medical records were searched to determine neuropathic pain syndromes treated, the presence of allodynia, previous analgesic medications, treatment duration and outcome.

RESULTS

L5%P was prescribed for 97 patients, most frequently for persistent postsurgical NP (n=26), postherpetic neuralgia (n=24) and cancer-related NP (n=18). Six patients had no history of cancer and two patients never applied L5%P. Reviewers classed L5%P analgesic efficacy as 'potent' in 38% of patients with postherpetic neuralgia, 35% of patients with postsurgical pain, 27% of patients with NP after other treatments for cancer and 12% of patients with NP attributed to cancer alone. Allodynia featured in at least 60% of patients. Where allodynia was present, the efficacy of L5%P was assessed as 'potent' in 38% and 'partial' in 24%, but 'ineffective' in 26%, and 'causing worse pain' in 3.4% of patients. Treatment duration extended longer than one month in 52 patients, longer than two months in 29 patients and longer than one year in 13 patients. Therapy was ceased due to skin irritation in seven patients. The outcomes in relation to other reports are discussed.

CONCLUSION

The present data support trials of L5%P for cancer patients with NP syndromes associated with allodynia.

Guidelines for the diagnosis and management of neuropathic pain: consensus of a group of Latin American experts

These consensus guidelines have been developed by a group of Latin American experts in pain management, to point out patterns and make practical recommendations to guide the diagnosis, identify warning signs (yellow and red flags), and establish comprehensive medical management (pharmacologic and nonpharmacologic treatment) and monitoring plans for patients enduring neuropathic pain. From the viewpoint of pharmacologic management, drugs are classified into groups according to efficacy, availability/accessibility, and safety criteria. Drugs are recommended for use depending on the disease and particular circumstances of each patient, with an approach that favors multimodal treatment while taking into consideration the idiosyncrasies of medical practice in Latin America.

Sodium channel blockers for the treatment of neuropathic pain

Drugs that block voltage-gated sodium channels are efficacious in the management of neuropathic pain. Accordingly, this class of ion channels has been a major focus of analgesic research both in academia and in the pharmaceutical/biotechnology industry. In this article, we review the history of the use of sodium channel blockers, describe the current status of sodium channel drug discovery, highlight the challenges and hurdles to attain sodium channel subtype selectivity, and review the potential usefulness of selective sodium channel blockers in neuropathic pain.

Phantom breast syndrome

Phantom breast syndrome is a type of condition in which patients have a sensation of residual breast tissue and can include both non-painful sensations as well as phantom breast pain. The incidence varies in different studies, ranging from approximately 30% to as high as 80% of patients after mastectomy. It seriously affects quality of life through the combined impact of physical disability and emotional distress. The breast cancer incidence rate in India as well as Western countries has risen in recent years while survival rates have improved; this has effectively increased the number of women for whom post-treatment quality of life is important. In this context, chronic pain following treatment for breast cancer surgery is a significantly under-recognized and under-treated problem. Various types of chronic neuropathic pain may arise following breast cancer surgery due to surgical trauma. The cause of these syndromes is damage to various nerves during surgery. There are a number of assumed factors causing or perpetuating persistent neuropathic pain after breast cancer surgery. Most well-established risk factors for developing phantom breast pain and other related neuropathic pain syndromes are severe acute postoperative pain and greater postoperative use of analgesics. Based upon current evidence, the goals of prophylactic strategies could first target optimal peri-operative pain control and minimizing damage to nerves during surgery. There is some evidence that chronic pain and sensory abnormalities do decrease over time. The main group of oral medications studied includes anti-depressants, anticonvulsants, opioids, N-methyl-D-asparate receptor antagonists, mexilitine, topical lidocaine, cannabinoids, topical capsaicin and glysine antagonists. Neuromodulation techniques such as motor cortex stimulation, spinal cord stimulation, and intrathecal drug therapies have been used to treat various neuropathic pain syndromes.

Depression and cancer: an unexplored and unresolved emergent issue in elderly patients

Despite the high prevalence of depressive disorders in cancer patients and elderly people, the topic of depression in elderly cancer patients still remains unexplored. This emerges from a systematic review of the literature conducted to investigate issues of depression, diagnosis, pathogenesis, treatment and their complex neuroimmunobiological interactions. Indeed, it becomes apparent that depression in elderly patients with cancer may have a peculiar phenomenology. In addition, the moderate rate of major depressive disorder and the high rate of minor depressive disorder are accompanied by subthreshold forms of depression that are at risk to be underrecognized and untreated. Immune dysfunction may represent a common pathogenic ground of depression, cancer and aging. This may have important implications for treatment. In the near future, we need to develop validated mood disorder diagnoses and verify antidepressant treatment efficacy for elderly cancer patients with depression in order to improve their clinical outcome and quality of life.

Recent advances in the pharmacological management of pain

Pain is an unpleasant sensation that originates from ongoing or impending tissue damage. Management of different types of pain (acute, postoperative, inflammatory, neuropathic or cancer) is the most frequent issue encountered by clinicians and pharmacological therapy is the first line of approach for the treatment of pain. This review presents and discusses recent clinical advances regarding both the improvements in delivery of analgesic drugs and improvements in the design of analgesic molecules. The new modalities of administration of analgesics used in the clinic are reviewed, including skin patches, oral and mucosal sprays, transdermal delivery systems and intranasal administration. New insights are then presented on standard drugs used to relieve pain, such as opioids (including tramadol), NSAIDs including selective cyclo-oxygenase-2 inhibitors, paracetamol (acetaminophen), local anaesthetics and adjuvant analgesics such as antidepressants, anticonvulsants (gabapentin and pregabalin), cannabinoids, ketamine and others (e.g. nefopam). Although the understanding of pain mechanisms has improved significantly recently, much more is yet to be discovered and awaited. Broadening of our knowledge is needed to improve basic and clinical research in this field in order to better alleviate pain in millions of people.

Antidepressants for the treatment of chronic pain

Chronic pain represents one of the most important public health problems and, in addition to classical analgesics, antidepressants are an essential part of the therapeutic strategy. This article reviews available evidence on the efficacy and safety of antidepressants in major chronic pain conditions; namely, neuropathic pain, headaches, low back pain, fibromyalgia, irritable bowel syndrome (IBS) and cancer pain. Studies, reviews and meta-analyses published from 1991 to March 2008 were retrieved through MEDLINE, PsycINFO and the Cochrane database using numerous key words for pain and antidepressants. In summary, evidence supports the use of tricyclic antidepressants in neuropathic pain, headaches, low back pain, fibromyalgia and IBS. The efficacy of the newer serotonin and norepinephrine reuptake inhibitors is less supported by evidence, but can be recommended in neuropathic pain, migraines and fibromyalgia. To date, evidence does not support an analgesic effect of serotonin reuptake inhibitors, but beneficial effects on well-being were reported in several chronic pain conditions. These results are discussed in the light of current insights in the neurobiology of pain, the reciprocal relationship between pain and depression, and future developments in this field of research.

Treatment of depressive symptoms in patients with early stage breast cancer undergoing adjuvant therapy

BACKGROUND

Studies have shown that there is a high prevalence of depression in cancer patients. Women with breast cancer may have an even higher risk of depression particularly in a postmenopausal or estrogen deficiency state. A small number of randomized controlled trials have examined the efficacy of antidepressants compared to that of a placebo in cancer patients, but some results have been difficult to interpret due to a heterogeneous patient group. In the current investigation, we screened newly diagnosed early stage breast cancer patients for depressive symptoms prior to the initiation of adjuvant therapy and investigated whether the oral antidepressant fluoxetine affected depressive symptoms, completion of adjuvant treatment, and quality of life.

METHODS

Patients with newly diagnosed early stage breast cancer were screened for depressive symptoms prior to the initiation of adjuvant therapy. Patients with depressive symptoms were randomized to a daily oral fluoxetine or a placebo. Patients were then followed for 6 months and evaluated for quality of life, completion of adjuvant treatment, and depressive symptoms.

RESULTS

A high percentage of patients with newly diagnosed early stage breast cancer were found to have depressive symptoms prior to the initiation of adjuvant therapy. The use of fluoxetine for 6 months resulted in an improvement in quality of life, a higher completion of adjuvant treatment (chemotherapy, hormonal therapy, chemotherapy plus hormonal therapy), and a reduction in depressive symptoms compared to patients who received placebo.

CONCLUSIONS

An antidepressant should be considered for early stage breast cancer patients with depressive symptoms who are receiving adjuvant treatment.

Antidepressants for neuropathic pain

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 3, 2005 of The Cochrane Library. For many years antidepressant drugs have been used to manage neuropathic pain, and are often the first choice treatment. It is not clear, however, which antidepressant is more effective, what role the newer antidepressants can play in treating neuropathic pain, and what adverse effects are experienced by patients.

OBJECTIVES

To determine the analgesic effectiveness and safety of antidepressant drugs in neuropathic pain.

SEARCH STRATEGY

Randomised controlled trials (RCTs) of antidepressants in neuropathic pain were identified in MEDLINE (1966 to Oct 2005); EMBASE (1980 to Oct 2005); the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Issue 3, 2005; and the Cochrane Pain, Palliative and Supportive Care Trials Register (May 2002). Additional reports were identified from the reference list of the retrieved papers, and by contacting investigators.

SELECTION CRITERIA

RCTs reporting the analgesic effects of antidepressant drugs in adult patients, with subjective assessment of pain of neuropathic origin. Studies that included patients with chronic headache and migraine were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors agreed the included studies, extracted data, and assessed methodological quality independently. Sixty one trials of 20 antidepressants were considered eligible (3293 participants) for inclusion. Relative Risk (RR) and Number-Needed-to-Treat (NNTs) were calculated from dichotomous data for effectiveness and adverse effects. This update includes 11 additional studies (778 participants).

MAIN RESULTS

Sixty one RCTs were included in total. Tricyclic antidepressants (TCAs) are effective and have an NNT of 3.6 (95% CI 3 to 4.5) RR 2.1 (95% CI 1.8 to 2.5) for the achievement of at least moderate pain relief. There is limited evidence for the effectiveness of the newer SSRIs but no studies of SNRIs were found. Venlafaxine (three studies) has an NNT of 3.1 (95% CI 2.2 to 5.1) RR 2.2 (95% CI 1.5 to 3.1). There were insufficient data to assess effectiveness for other antidepressants such as St Johns Wort and L-tryptophan. For diabetic neuropathy the NNT for effectiveness was 1.3 (95% CI 1.2 to 1.5) RR 12.4 (95% CI 5.2 to 29.2) (five studies); for postherpetic neuralgia 2.7 (95% CI 2 to 4.1), RR 2.2 (95% CI 1.6 to 3.1) (four studies). There was evidence that TCAs are not effective in HIV-related neuropathies. The number needed to harm (NNH) for major adverse effects defined as an event leading to withdrawal from a study was 28 (95% CI 17.6 to 68.9) for amitriptyline and 16.2 (95% CI 8 to 436) for venlafaxine. The NNH for minor adverse effects was 6 (95% CI 4.2 to 10.7) for amitriptyline and 9.6 (95% CI 3.5 to 13) for venlafaxine.

AUTHORS' CONCLUSIONS

This update has provided additional confirmation on the effectiveness of antidepressants for neuropathic pain and has provided new information on another antidepressant - venlafaxine. There is still limited evidence for the role of SSRIs. Whether antidepressants prevent the development of neuropathic pain (pre-emptive use) is still unclear. Both TCAs and venlafaxine have NNTs of approximately three. This means that for approximately every three patients with neuropathic pain who are treated with either of these antidepressants, one will get at least moderate pain relief. There is evidence to suggest that other antidepressants may be effective but numbers of participants are insufficient to calculate robust NNTs. SSRIs are generally better tolerated by patients and more high quality studies are required.

Voltage-gated Na+channels in neuropathic pain

Neuropathic pain occurs as a result of some form of injury to the nervous system. Although the basis of the disease remains to be fully elucidated, numerous studies have suggested a major role for ion channels in the pathogenesis of neuropathic pain. As Na+ channels play a fundamental role in not only the generation but also in the conduction of an action potential, they have received considerable attention in the aetiology of pain sensation and have become important pharmacological targets. In this review, the authors discuss the importance of specific Na+ channel isoforms in the pathophysiology of neuropathic pain and the present use of Na+ channel antagonists in the treatment of neuropathic pain.

EFNS guidelines on pharmacological treatment of neuropathic pain

Neuropathic pain treatment remains unsatisfactory despite a substantial increase in the number of trials. This EFNS Task Force aimed at evaluating the existing evidence about the pharmacological treatment of neuropathic pain. Studies were identified using first the Cochrane Database then Medline. Trials were classified according to the aetiological condition. All class I and II controlled trials (according to EFNS classification of evidence) were assessed, but lower-class studies were considered in conditions that had no top level studies. Only treatments feasible in an outpatient setting were evaluated. Effects on pain symptoms/signs, quality of life and comorbidities were particularly searched for. Most of the randomized controlled trials included patients with postherpetic neuralgia (PHN) and painful polyneuropathies (PPN) mainly caused by diabetes. These trials provide level A evidence for the efficacy of tricyclic antidepressants, gabapentin, pregabalin and opioids, with a large number of class I trials, followed by topical lidocaine (in PHN) and the newer antidepressants venlafaxine and duloxetine (in PPN). A small number of controlled trials were performed in central pain, trigeminal neuralgia, other peripheral neuropathic pain states and multiple-aetiology neuropathic pains. The main peripheral pain conditions respond similarly well to tricyclic antidepressants, gabapentin, and pregabalin, but some conditions, such as HIV-associated polyneuropathy, are more refractory. There are too few studies on central pain, combination therapy, and head-to-head comparison. For future trials, we recommend to assess quality of life and pain symptoms or signs with standardized tools.

Use of tricyclic antidepressants in older patients with painful neuropathies

OBJECTIVE

To describe patterns of use of tricyclic antidepressants (TCAs) (e.g., amitriptyline, nortriptyline) in older patients with painful neuropathies.

RESEARCH DESIGN AND METHODS

Using a large US health insurance claims database, we identified all persons who: (1) received a TCA between 1 January 1999 and 30 June 2001, (2) were aged > or =65 years as of the date of their first prescription for a TCA during this period, and (3) had one or more health care encounters for the treatment of a painful neuropathy in the 30-day period immediately preceding their initial receipt of a TCA. We then examined the prevalence of selected comorbidities and/or concurrent use of medications that might render the prescribing of a TCA inappropriate, based on a listing of contraindications, warnings, and precautions found in the package inserts for these agents. Patterns of TCA use also were examined, based on information on paid claims.

RESULTS

A total of 1,732 patients met all inclusion and exclusion criteria for the study. Their mean age was 74.6 years; 60.3% were women. Amitriptyline was the most frequently prescribed TCA (79.4% of patients). Forty-one percent of study subjects receiving TCAs had conditions--primarily cardiovascular--that render the use of such agents potentially inappropriate. The mean daily dose of TCAs was universally low (about 23 mg).

CONCLUSIONS

The high prevalence of conditions rendering the use of TCAs potentially inappropriate, along with relatively low daily dosages, suggest that many older patients with painful neuropathies who are prescribed these agents may be suboptimally treated.

The Impact of Therapy on Quality of Life and Mood in Neuropathic Pain: What Is the Effect of Pain Reduction?

Mood and quality of life (QOL) outcomes vary widely in neuropathic pain trials. This may be a result of variable analgesia and other treatment effects. We evaluated the relationship between pain reduction and mood/QOL in neuropathic pain. Pain, side effects, QOL, and mood from a trial of morphine, gabapentin, and a morphine-gabapentin combination were examined. Baseline QOL was impaired according to Short Form Health Survey (SF-36) scores. Baseline mood, according to Profile of Mood States scores, was comparable to that of a nondepressed population. Pain reduction with all three active trial treatments correlated with improved QOL. Pain reduction with morphine and with gabapentin correlated with improved mood. Pain reduction with a morphine-gabapentin combination correlated with improvement in only one of several domains of the Profile of Mood States. Severity of sedation, constipation, and dry mouth during any treatment did not correlate with mood/QOL changes. These results can be interpreted to imply that larger analgesic treatment effect sizes lead to more substantial improvements in QOL and/or mood. However, other beneficial or adverse treatment-related side effects may also affect mood/QOL. Therefore, future studies are needed to also evaluate the impact of treatment-related side effects on mood/QOL in analgesic trials.

Use of antidepressants in older patients with co-morbid medical conditions: guidance from studies of depression in somatic illness

Advanced age and medical complexity are characteristics not often associated with participation in randomised, placebo-controlled trials of antidepressants. Thus, evidence for the efficacy of antidepressant treatment among typical seniors with somatic illness and advanced age is scant. Furthermore, there appears to be no clear empirically based delineation between depressive symptoms and depressive disorders among very old, physically ill adults. The increasing numbers of antidepressants and adjunctive medications add to the practitioner's perplexity when confronted with a very old, very depressed patient. Nonetheless, a growing body of evidence from antidepressant studies in the context of age-related somatic illnesses allows reasonable inferences to guide diagnosis and treatment. Once the practitioner and patient agree upon an antidepressant trial, the benefits of prescribed medication should be assessed within the first days rather than first weeks of treatment. The patient and practitioner should expect to escalate the antidepressant to the established therapeutic range rather than seek the lowest dose that is effective. Patients who experience no benefit whatsoever within the first weeks of treatment despite being within the therapeutic range should be offered an alternative promptly. With the results of studies of depression in co-morbid disorders and analyses of treatment response trajectory, the practitioner can be assured that advanced age, physical illness and depression need not go hand in hand.

Antidepressants for neuropathic pain

BACKGROUND

For many years antidepressant drugs have been used to manage neuropathic pain, and are often the first choice treatment. It is not clear, however, which antidepressant is more effective, what role the newer antidepressants can play in treating neuropathic pain, and what adverse effects are experienced by patients.

OBJECTIVES

To determine the analgesic effectiveness and safety of antidepressant drugs in neuropathic pain. Migraine and headache studies were not considered.

SEARCH STRATEGY

Randomised trials of antidepressants in neuropathic pain were identified in MEDLINE (1966 to Dec 2003); EMBASE (1980 to Dec 2003); the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library 2004, Issue 1; and the Cochrane Pain, Palliative and Supportive Care Trials Register (May 2002). Additional reports were identified from the reference list of the retrieved papers, and by contacting investigators.

SELECTION CRITERIA

Randomised trials reporting the analgesic effects of antidepressant drugs in adult patients, with subjective assessment of pain of neuropathic origin. Studies that included patients with chronic headache and migraine were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers agreed the included studies, extracted data, and assessed methodological quality independently. Fifty trials of 19 antidepressants were considered eligible (2515 patients) for inclusion. Relative Risk (RR) estimates and Number-Needed-to-Treat (NNTs) were calculated from dichotomous data for effectiveness and adverse effects.

MAIN RESULTS

Tricyclic antidepressants (TCAs) are effective treatments for the treatment of neuropathic pain. Amitriptyline has an NNT of 2 (95%CI 1.7 to 2.5) RR 4.1(95%CI 2.9-5.9) for the achievement of at least moderate pain relief. There is limited evidence for the effectiveness of the newer selective serotonin reuptake inhibitor antidepressant drugs (SSRIs). There were insufficient data for an assessment of evidence of effectiveness for other antidepressants such as St Johns Wort, venlafaxine and L-tryptophan. For diabetic neuropathy the NNT for effectiveness was 1.3 (95%CI 1.2 to 1.5) RR 12.4(95%CI 5.2-29.2) (five studies); for postherpetic neuralgia 2.2 (95%CI 1.7 to 3.1), RR 4.8(95%CI 2.5-9.5)(three studies). There was evidence that TCAs are not effective in HIV-related neuropathies. The number needed to harm(NNH) for major adverse effects defined as an event leading to withdrawal from a study was 16 (95%CI: 10-45). The NNH for minor adverse effects was 4.6 (95%CI 3.3-6.7)

AUTHORS' CONCLUSIONS

Antidepressants are effective for a variety of neuropathic pains. The best evidence available is for amitriptyline. There are only limited data for the effectiveness of SSRIs. It is not possible to identify the most effective antidepressant until more studies of SSRIs are conducted.

A treatment algorithm for neuropathic pain

BACKGROUND

Neuropathic pain is a chronic pain syndrome caused by drug-, disease-, or injury-induced damage or destruction of sensory neurons within the dorsal root ganglia of the peripheral nervous system. Characteristic clinical symptoms include the feeling of pins and needles; burning, shooting, and/or stabbing pain with or without throbbing; and numbness. Neuronal hyperexcitability represents the hallmark cellular mechanism involved in the underlying pathophysiology of neuropathic pain. Although the primary goal is to alleviate pain, clinicians recognize that even the most appropriate treatment strategy may be, at best, only able to reduce pain to a more tolerable level.

OBJECTIVE

The purpose of this review is to propose a treatment algorithm for neuropathic pain that health care professionals can logically follow and adapt to the specific needs of each patient. The algorithm is intended to serve as a general guide to assist clinicians in optimizing available therapeutic options.

METHODS

A comprehensive review of the literature using the PubMed, MEDLINE, Cochrane, and Toxnet databases was conducted to design and develop a novel treatment algorithm for neuropathic pain that encompasses agents from several drug classes, including antidepressants, antiepileptic drugs, topical antineuralgic agents, narcotics, and analgesics, as well as various treatment options for refractory cases.

RESULTS

Any of the agents in the first-line drug classes (tricyclic antidepressants, antiepileptic drugs, topical antineuralgics, analgesics) may be used as a starting point in the treatment of neuropathic pain. If a patient does not respond to treatment with at least 3 different agents within a drug class, agents from a second drug class may be tried. When all first-line options have been exhausted, narcotic analgesics or refractory treatment options may provide some benefit. Patients who do not respond to monotherapy with any of the first- or second-line agents may respond to combination therapy or may be candidates for referral to a pain clinic. Because the techniques used at pain clinics tend to be invasive, referrals to these clinics should be reserved for patients who are truly refractory to all forms of pharmacotherapy.

CONCLUSIONS

Neuropathic pain continues to be one of the most difficult pain conditions to treat. With the proposed algorithm, clinicians will have a framework from which to design a pain treatment protocol appropriate for each patient. The algorithm will also help streamline referrals to specialized pain clinics, thereby reducing waiting list times for patients who are truly refractory to traditional pharmacotherapy.

Psychiatric issues in older cancer patients

Although many patients are surviving longer than in the past, a cancer diagnosis may shatter the dream of a dignified old age for elderly patients. Cancer diagnosis and treatment often produce psychologic stresses resulting from the actual symptoms of the disease, as well as perceptions of the disease and its stigma. Concerns related to cancer have particular meaning for aging individuals who undergo these situations in the context of retirement, widowhood, other medical disabilities and other losses. Today, patients and families are more interested in treatment issues, and quality of life, both during and after treatment. In this article we discuss late life depression, anxiety and delirium as they relate to elderly patients coping with cancer.

Use of potentially inappropriate pain-related medications in older adults with painful neuropathic disorders

BACKGROUND

Although older adults with painful neuropathic disorders (PNDs) would appear to be at elevated risk for receiving potentially inappropriate pain-related medications, the extent of such drug use in this population is unknown.

OBJECTIVE

The goal of this study was to assess the use of potentially inappropriate pain-related medications among patients with PNDs aged >or=65 years.

METHODS

Using a large, integrated US health insurance database, we identified all persons aged >or=65 years with >or=2 medical encounters involving diagnoses of PNDs during calendar year 2000. Patients with <30 days of continuous eligibility for health benefits during the study year were excluded from the sample. Use of potentially inappropriate pain-related medications (as defined by the 1997 Beers criteria) was then examined based on information contained in paid pharmacy claims for all remaining patients.

RESULTS

We identified 22,668 patients with PNDs aged >or=65 years (mean [SD] age, 73.9 [6.0] years; 58.6% female). Almost one half (11,233 [49.6%]) of patients received >or=1 potentially inappropriate pain-related medication, including propoxyphene (26.7%) and amitriptyline (10.2%). Women were more likely than men to receive these medications (54.2% vs 43.0%, respectively; P<0.01), and use increased with age (47.6%, 51.8%, and 52.8% in those aged 65-74 years, 75-84 years, and >or=85 years, respectively; overall comparison, P<0.01). Among patients with only 1 PND, the use of potentially inappropriate medications was highest among those with postherpetic neuralgia (70.1%).

CONCLUSIONS

Use of potentially inappropriate pain-related medications among older adults with PNDs is common. Further research is needed to ascertain whether the benefits of these agents outweigh their risks in this population.

Therapeutic outcome in neuropathic pain: relationship to evidence of nervous system lesion

Treatment outcome in patients with neuropathic pain (NP) is often variable and disappointing. We tested the hypothesis that patients with clear evidence of nervous system lesion respond better to pharmacological treatment with documented effect on NP than patients with poor or no evidence of nervous system lesion. Furthermore, we examined whether specific symptoms or signs were associated with treatment outcome. A total of 214 patients with suspected non-cancer NP were divided into four groups with graded evidence of nervous system lesion based on medical history, bedside sensory examination, quantitative sensory tests, electrophysiology, and neuroimaging. Patients were treated with imipramine guided by plasma-drug concentrations. Gabapentin 2400 mg/day was given in case of treatment failure or if imipramine treatment was not possible. Two hundred patients completed the study. Global pain relief was similar in the four groups. There was no association between evidence of nervous system lesion and treatment outcome. Classical NP signs: abnormal temporal summation, cold and brush allodynia, and abnormal sensibility to temperature were also unrelated to outcome. Treatment outcome was similar in peripheral and central definite NP. Neither definite evidence of nervous system lesion nor abnormal sensory phenomena seems to predict for good outcome of therapy with imipramine or gabapentin in patients with suspected neuropathic pain.

TDM-Based Imipramine Treatment in Neuropathic Pain

Tricyclic antidepressants (TCA) are the best-documented treatment of neuropathic pain. TCAs have a pronounced interindividual pharmacokinetic variability and a narrow therapeutic index. The aim of this study was to characterize the plasma concentration-effect relationship of imipramine in neuropathic pain and to determine the usefulness of therapeutic drug monitoring (TDM) of TCA treatment in a population with noncancer chronic pain. To do this, 83 patients with chronic noncancer neuropathic pain were included. Information on previous use of TCA was collected, and patients were tested for the presence of hyperalgesia. Pain intensity and pain relief were recorded, and the Short Form McGill Pain Questionnaire and Major Depression Inventory were completed before and during a TDM-based imipramine treatment. Imipramine dose was increased in steps of 25 mg/d every second week, and blood samples were taken at every dose. Endpoints were best possible pain relief, unacceptable side effects, or insufficient pain relief despite plasma drug level > 500 nmol/L. Dose range used was 10-300 mg/d. The study showed that imipramine 75 mg/d caused a 36-fold interindividual variation in steady-state plasma drug concentrations. In 46 responders (global pain relief > 25%) the plasma drug concentration at which an individual maximal analgesic effect was obtained ranged from 50 to 1400 nmol/L, but for the majority it was below 400 nmol/L. The concentration-effect relationship was similar for patients with central versus peripheral neuropathic pain and independent of the presence of hyperalgesia. Previous treatment failure with non-TDM TCA treatment was not a predictor of poor response to TDM-based treatment. In conclusion, there is a pronounced interindividual variability in concentration-effect relationship for imipramine treatment in neuropathic pain, but the majority of patients obtain a maximal analgesic effect at drug levels below 400 nmol/L. The concentration-effect relationship is similar for patients with central and peripheral neuropathic pain. Further studies are needed to document if TDM improves pain relief; however, TDM reduces the risk for toxicity.

Current pharmacologic approaches to treating neuropathic pain

Most neuropathic analgesic medications have been introduced initially for other medical conditions. Anticonvulsants, local anesthetics, and antidepressants later were found to be effective in the treatment of neuropathic pain. Carbamazepine and the newer anticonvulsants such as gabapentin, lamotrigine, topiramate, and oxcarbazepine are being used as first-line or adjunctive therapy. The newer agents have less potential for drug interactions and a more favorable side-effect profile. Lidocaine administered systemically or topically is useful for some peripheral and central neuropathic pain conditions. The tricyclic antidepressants amitriptyline, nortriptyline, and desipramine have been shown to be effective for the management of neuropathic pain, independent of their antidepressant property. All of the available analgesics have considerable side effects, which necessitate careful titration. Future drug research may focus on developing medications specifically for neuropathic pain. These designer agents may have more desirable action without the unwanted side effects.

Evaluation of efficacy of the perioperative administration of venlafaxine XR in the prevention of postmastectomy pain syndrome

Postmastectomy pain syndrome (PMPS) is a neuropathic pain syndrome that may develop following breast surgery. Venlafaxine has been shown to be efficacious in the management of PMPS. The preemptive administration of venlafaxine has been shown to be efficacious in reducing the incidence of neuropathic pain in the rat model. We examined the efficacy of administering either venlafaxine or placebo for two weeks starting the night before surgery to 100 patients scheduled for either partial or radical mastectomy with axillary dissection. Patients were administered PCA morphine for the first 24 hours following surgery and then acetaminophen/oxycodone tablets. Pain scores were recorded at rest and movement on day 1, at 1 month, and at 6 months after surgery. At 6 months postoperatively, the presence of pain in the chest, arm, and axilla; edema; decreased sensation in the operative area; and phantom breast pain were recorded. There was no difference in postoperative opioid use. Pain scores with movement were lower in the venlafaxine group at 6 months. Pain scores at all other time intervals were similar. There was a significant decrease in the incidence of chest wall pain (55% vs. 19%, P = 0.0002), arm pain (45% vs. 17%, P = 0.003), and axilla pain (51% vs. 19%, P = 0.0009) between the control group and the venlafaxine group, respectively. No significant differences were noted between the two groups with regard to edema, phantom pain, or sensory changes. We conclude that the perioperative administration of venlafaxine beginning the night prior to surgery significantly reduces the incidence of PMPS following breast cancer surgery.

The effectiveness of intravenous ketamine and lidocaine on peripheral neuropathic pain

BACKGROUND

Neuropathic pain is often severe and resistant to pharmacological treatment. The aims of the present study were to assess the analgesic effect of ketamine and lidocaine and to investigate if measurement of different variables of sensibility could be used to identify responders. We also wanted to study if treatment resulted in changes of sensibility.

METHODS

Twelve patients with long-lasting peripheral neuropathic pain of traumatic origin were included. The effects of ketamine hydrochloride (Ketalar, Parke Davis) 0.4 mg/kg and lidocaine hydrochloride (Xylocain, Astra) 2.5 mg/kg were investigated. Saline was used as placebo. The intensity of continuous pain was measured by a visual analogue scale (VAS). Warm and cold perception as well as heat and cold pain thresholds were assessed. Sensibility to touch was also tested. Systemic plasma concentrations of lidocaine and ketamine were assessed.

RESULTS

The mean reduction in VAS-scores was 55%, 34% and 22% for ketamine, lidocaine and placebo, respectively. A significant difference was registered between ketamine and placebo (P = 0.009). Response to treatment (50% reduction in VAS-score during infusion) was recorded in 7/12 in the ketamine, 4/12 in the lidocaine and 2/12 in the placebo group. Quantitative sensory testing (QST) of thermal sensitivity and sensory tests for mechanical stimuli could not separate responders from non-responders and neither were the results from these assessments changed by the infusion of the drugs. Lidocaine and particularly ketamine were associated with frequent side-effects, the most common being somnolence and dizziness.

CONCLUSION

Ketamine showed a significant analgesic effect. The clinical usefulness is, however, limited by disturbing side-effects.

Evaluation of the anti-inflammatory and anti-nociceptive effects of different antidepressants in the rat

The present study was designed to compare the anti-inflammatory and anti-nociceptive effects of different classes of antidepressant drugs on the carrageenan paw oedema and tail-electric stimulation assays in the rat. Drugs were intraperitoneally administered 30 min prior to carrageenan or nociceptive testing. The non-selective noradrenaline (NA) and serotonin (5-HT) reuptake inhibitors imipramine, amitriptyline and clomipramine displayed anti-inflammatory activity in the carrageenan model of paw inflammation. The maximal degree of oedema inhibitions seen with these agents were 28.8, 41.5 and 46.8% for 5, 10 and 20 mg kg(-1) amitriptyline, 26.2, 38.2 and 51.4% for 3.75, 7.5 and 15 mg kg(-1) imipramine and 51.2 and 54.1% for 16 and 32 mg kg(-1) clomipramine, respectively. The heterocyclic agent trazodone significantly inhibited paw oedema by 46 and 41% at 1 and 2h after dosing at the highest dose (40 mg kg(-1)) examined. Fluoxetine, a selective 5-HT reuptake inhibitor (SSRI) caused dose-related reduction of paw oedema, with 20.7% inhibition at the dose of 10 mg kg(-1). In contrast, sertraline, another SSRI caused dose-dependent enhancement of paw oedema. All antidepressant drugs in the study showed anti-nociceptive properties in the tail-electric stimulation assay with amitriptyline and trazodone being the most effective in this respect. Taken together, data in the present study confirm anti-inflammatory and anti-nociceptive effect for some antidepressant drugs and indicate that SSRIs differently affects inflammation.

Fluoxetine versus placebo in advanced cancer outpatients: a double-blinded trial of the Hoosier Oncology Group

PURPOSE

To determine whether fluoxetine improves overall quality of life (QOL) in advanced cancer patients with symptoms of depression revealed by a simple survey.

PATIENTS AND METHODS

One hundred sixty-three patients with an advanced solid tumor and expected survival between 3 and 24 months were randomly assigned in a double-blinded fashion to receive either fluoxetine (20 mg daily) or placebo for 12 weeks. Patients were screened for at least minimal depressive symptoms and assessed every 3 to 6 weeks for QOL and depression. Patients with recent exposure to antidepressants were excluded.

RESULTS

The groups were comparable at baseline in terms of age, sex, disease distribution, performance status, and level of depressive symptoms. One hundred twenty-nine patients (79%) completed at least one follow-up assessment. Analysis using generalized estimating equation modeling revealed that patients treated with fluoxetine exhibited a significant improvement in QOL as shown by the Functional Assessment of Cancer Therapy-General, compared with patients given placebo (P =.01). Specifically, the level of depressive symptoms expressed was lower in patients treated with fluoxetine (P =.0005), and the subgroup of patients showing higher levels of depressive symptoms on the two-question screening survey were the most likely to benefit from treatment.

CONCLUSION

In this mix of patients with advanced cancer who had symptoms of depression as determined by a two-question bedside survey, use of fluoxetine was well tolerated, overall QOL was improved, and depressive symptoms were reduced.

Advances in cancer pain management

Although most patients with cancer pain can attain a favorable balance between analgesia and side effects with a conventional approach to opioid therapy, a substantial minority cannot. For these patients, an important subgroup of whom have neuropathic pain, alternative therapeutic strategies are needed. With a detailed assessment, clinicians should be able to choose among the large and diverse group of options available and implement an approach, or combination of approaches, that have a high probability of improving analgesic outcomes.

Venlafaxine in neuropathic pain following treatment of breast cancer

Amitriptyline effectively relieves neuropathic pain following treatment of breast cancer. However, adverse effects are a major problem. Venlafaxine has no anticholinergic effects and could have a better compliance. The aim of the study was to evaluate the effectiveness of venlafaxine in neuropathic pain. The study was a randomized, double-blind, crossover comparison of venlafaxine and inactive placebo. The study lasted 10 weeks. The number of tablets (18.75 mg) taken daily was increased by one at a 1 week interval. Pain intensity and pain relief were registered daily by a diary and by a questionnaire and a computer program (Painscreen) on each visit. Adverse effects were evaluated with the diaries and a 10-item list on each visit. Also, anxiety and depression were measured on each visit. Venous blood samples were collected before the treatment and at 4 weeks for the determination of the serum levels of venlafaxine and its three metabolites. Thirteen patients were analysed. The average daily pain intensity as reported in the diary (primary outcome) was not significantly reduced by venlafaxine compared with placebo. However, the average pain relief (diary) and the maximum pain intensity (retrospective assessment by the computer program) were significantly lower with venlafaxine compared with placebo. Anxiety and depression were not affected. Adverse effects did not show significant differences between treatments. The two poor responders had low venlafaxine concentrations whereas the two slow hydroxylizers had high venlafaxine concentrations and excellent pain relief. Thus, higher doses could be used in order to improve pain relief.

Treatment of depression in patients with breast cancer: a comparison between paroxetine and amitriptyline

In the context of chronic physical illness, such as breast cancer, depression is associated with increased morbidity, longer periods of hospitalization, and greater overall disability. Prompt diagnosis and effective treatment is. therefore, essential. Several small studies have established the efficacy of tricyclic antidepressants (TCAs) in this setting, and the selective serotonin reuptake inhibitors (SSRIs) would appear to be an alternative therapeutic option because of their established efficacy and better tolerability profile. This was a multicenter. double-blind, parallel-group study in which 179 women with breast cancer were randomized to treatment with either the SSRI paroxetine (20-40 mg/day), or the TCA, amitriptyline (75-150 mg/day). After 8-weeks treatment, depressive symptomatology had improved markedly and to a similar extent in both groups on the Montgomery Asberg Depression Rating Scale. Clinical global impression (CGI) Global improvement and Patient global evaluation scales indicated that patients were minimally to much improved at study endpoint: a change from moderately/mildly ill to borderline ill on the CGI severity of Illness scale. A steady improvement in quality of life was also observed in both groups. There were no clinically significant differences between the groups. In total, 47 (53.4%) patients in the paroxetine group and 53 (59.6%) patients in the amitriptyline group had adverse experiences, the most common of which were the well-recognized side-effects of the antidepressant medications or chemotherapy. Anticholinergic effects were almost twice as frequent in the amitriptyline group (19.1%) compared with paroxetine (11.4%). This study has demonstrated that paroxetine is a suitable alternative to amitriptyline for the treatment of depression in patients with breast cancer.