S2k-Leitlinie: Diagnose und nicht interventionelle Therapie neuropathischer Schmerzen: Zusammenfassung der Leitlinie der Deutschen Gesellschaft für Neurologie

Deprescribing of antidepressants: development of indicators of high-risk and overprescribing using the RAND/UCLA Appropriateness Method

BACKGROUND

Antidepressants are first-line medications for many psychiatric disorders. However, their widespread long-term use in some indications (e.g., mild depression and insomnia) is concerning. Particularly in older adults with comorbidities and polypharmacy, who are more susceptible to adverse drug reactions, the risks and benefits of treatment should be regularly reviewed. The aim of this consensus process was to identify explicit criteria of potentially inappropriate antidepressant use (indicators) in order to support primary care clinicians in identifying situations, where deprescribing of antidepressants should be considered.

METHODS

We used the RAND/UCLA Appropriateness Method to identify the indicators of high-risk and overprescribing of antidepressants. We combined a structured literature review with a 3-round expert panel, with results discussed in moderated meetings in between rounds. Each of the 282 candidate indicators was scored on a 9-point Likert scale representing the necessity of a critical review of antidepressant continuation (1-3 = not necessary; 4-6 = uncertain; 7-9 = clearly necessary). Experts rated the indicators for the necessity of review, since decisions to deprescribe require considerations of patient risk/benefit balance and preferences. Indicators with a median necessity rating of ≥ 7 without disagreement after 3 rating rounds were accepted.

RESULTS

The expert panel comprised 2 general practitioners, 2 clinical pharmacologists, 1 gerontopsychiatrist, 2 psychiatrists, and 3 internists/geriatricians (total N = 10). After 3 assessment rounds, there was consensus for 37 indicators of high-risk and 25 indicators of overprescribing, where critical reviews were felt to be necessary. High-risk prescribing indicators included settings posing risks of drug-drug, drug-disease, and drug-age interactions or the occurrence of adverse drug reactions. Indicators with the highest ratings included those suggesting the possibility of cardiovascular risks (QTc prolongation), delirium, gastrointestinal bleeding, and liver injury in specific patient subgroups with additional risk factors. Overprescribing indicators target patients with long treatment durations for depression, anxiety, and insomnia as well as high doses for pain and insomnia.

CONCLUSIONS

Explicit indicators of antidepressant high-risk and overprescribing may be used directly by patients and health care providers, and integrated within clinical decision support tools, in order to improve the overall risk/benefit balance of this commonly prescribed class of prescription drugs.

[Sequence variants of unknown significance in small fiber neuropathy : Characterization of a heterogeneous patient population]

BACKGROUND

In almost half of patients suffering from small fiber neuropathies (SFN), the etiology remains elusive. For these patients with "idiopathic SFN", symptomatic analgesic therapy is the only option. Reports on a potential genetic background of neuropathic pain syndromes are increasing and particularly in SFN patients, several genetic variants were found mainly located in genes encoding voltage-gated sodium channels. Although up to 30% of SFN patients show genetic alterations, most of these remain of "unknown pathogenic significance" and little is known about "genetic SFN".

OBJECTIVES

The study aimed to determine clinical characteristics of SFN patients carrying a rare genetic variant of unknown significance in pain-associated genes.

MATERIALS AND METHODS

From 2015 to 2020, 66 patients with primarily idiopathic SFN were examined and rare gene variants of unknown significance detected in 13/66 (20%) of these. A detailed medical history with focus on pain was recorded and patients filled in standardized questionnaires to assess physical and emotional burden due to pain.

RESULTS

The authors found 13/66 (20%) patients with rare variants of unknown significance located in pain-associated genes who reported pain refractory to analgesic treatment, a higher number of external factors influencing clinical symptoms, and a higher level of physical impairment and emotional stress due to pain compared with patients without such genetic variants.

CONCLUSIONS

Early genetic assessment is recommended to optimize the management of patients with potentially hereditary SFN. Early access to rehabilitation and mental support as well as a consequent elimination of external triggering factors should be granted.

[Diabetic neuropathy and diabetic foot syndrome (update 2023)]

These are the guidelines for diagnosis and treatment of diabetic neuropathy and diabetic foot.The position statement summarizes characteristic clinical symptoms and techniques for diagnostic assessment of diabetic neuropathy, including the complex situation of the diabetic foot syndrome. Recommendations for the therapeutic management of diabetic neuropathy, especially for the control of pain in sensorimotor neuropathy, are provided. The needs to prevent and treat diabetic foot syndrome are summarized.

[Practice of perioperative phantom limb pain prevention in Germany: a nationwide survey]

BACKGROUND

The prevalence of phantom limb pain after major amputation remains high and affected patients suffer from relevant impairments in the quality of life. Perioperative treatment strategies may prevent phantom limb pain. This study aims to assess the state of the perioperative anesthesiological pain management for major amputations. Furthermore, it analyzes potentials for optimization and barriers towards a better treatment of patients with amputations.

MATERIAL AND METHODS

This online survey was distributed by the German Society of Anesthesiology and Intensive Care Medicine (DGAI) mailing list of anesthesiological consultants. It was approved by the Charité ethics board.

RESULTS

Overall, 402 persons participated in this survey. Mostly, general anesthesia (85%), regional anesthesia (63%) and neuraxial anesthesia (49%) were performed in different combinations. Furthermore, 72% of participants reported using i.v. opioids postoperatively, mostly applied via patient-controlled analgesia (PCA). In contrast, preoperative regional anesthesia (74%) and gabapentinoids (67%) were seen as potential methods to improve treatment; however, barrier analysis revealed that treatment options are limited especially by organizational aspects and intrinsic patient factors.

CONCLUSION

This survey describes the current practice of phantom limb pain prevention in Germany. It shows an unmet need for specialized perioperative pain treatment. As the evidence regarding treatment recommendations is limited, further research questions can be deduced from this study.

Organisation und Durchführung der Schmerztherapie in deutschen Notaufnahmen – eine Onlineumfrage

Einleitung

Obwohl Schmerzen der häufigste Grund für eine Vorstellung in der Notaufnahme sind, ist ihre Erfassung und Therapie sehr heterogen organisiert und wird vielfach von Patienten als unzureichend beschrieben. Eine spezielle Leitlinie existiert bislang nicht und so wird beispielsweise die Delegation an die Notfallpflege nach Standard Operating Procedure (SOP) sehr unterschiedlich gehandhabt.

Methode

Mithilfe einer Umfrage erfolgte eine Ist-Analyse zur Organisation und Durchführung der akuten Schmerztherapie in deutschen Notaufnahmen. 18 Fragen wurden onlinebasiert erstellt und über das Notaufnahmeverzeichnis der DGINA e. V. (Deutsche Gesellschaft für interdisziplinäre Notfall- und Akutmedizin) und DIVI e. V. (Deutsche Interdisziplinäre Vereinigung für Intensiv- und Notfallmedizin) an die Leiter von 951 deutschen Notaufnahmen verschickt.

Ergebnis

Es konnten 166 vollständige Fragebögen ausgewertet werden. Die Erfassung der Schmerzen erfolgt bei 77,7 % der Notaufnahmen innerhalb der ersten 10 min nach Erstkontakt, meist mit der numerischen Rating-Skala (46,4 %). Obwohl 17,7 % nicht dauerhaft ärztlich besetzt sind, dürfen in insgesamt 32,5 % der Notaufnahmen Pflegekräfte keine eigenständige Schmerztherapie durchführen. Eine spezielle SOP gab es nur in 44,8 % der befragten Notaufnahmen. Die am häufigsten verwendeten Analgetika sind Piritramid und Morphin sowie Metamizol und Ibuprofen.

Schlussfolgerung

Eine entsprechende nationale Leitlinie könnte Handlungssicherheit geben und als Grundlage für angepasste, örtliche SOP helfen, Verzögerungen bei der akuten Schmerztherapie zu vermeiden.

Visualizing the Unseen: Illustrating and Documenting Phantom Limb Sensations and Phantom Limb Pain With C.A.L.A

Currently, there is neither a standardized mode for the documentation of phantom sensations and phantom limb pain, nor for their visualization as perceived by patients. We have therefore created a tool that allows for both, as well as for the quantification of the patient's visible and invisible body image. A first version provides the principal functions: (1) Adapting a 3D avatar for self-identification of the patient; (2) modeling the shape of the phantom limb; (3) adjusting the position of the phantom limb; (4) drawing pain and cramps directly onto the avatar; and (5) quantifying their respective intensities. Our tool (C.A.L.A.) was evaluated with 33 occupational therapists, physiotherapists, and other medical staff. Participants were presented with two cases in which the appearance and the position of the phantom had to be modeled and pain and cramps had to be drawn. The usability of the software was evaluated using the System Usability Scale and its functional range was evaluated using a self-developed questionnaire and semi-structured interview. In addition, our tool was evaluated on 22 patients with limb amputations. For each patient, body image as well as phantom sensation and pain were modeled to evaluate the software's functional scope. The accuracy of the created body image was evaluated using a self-developed questionnaire and semi-structured interview. Additionally, pain sensation was assessed using the SF-McGill Pain Questionnaire. The System Usability Scale reached a level of 81%, indicating high usability. Observing the participants, though, identified several operational difficulties. While the provided functions were considered useful by most participants, the semi-structured interviews revealed the need for an improved pain documentation component. In conclusion, our tool allows for an accurate visualization of phantom limbs and phantom limb sensations. It can be used as both a descriptive and quantitative documentation tool for analyzing and monitoring phantom limbs. Thus, it can help to bridge the gap between the therapist's conception and the patient's perception. Based on the collected requirements, an improved version with extended functionality will be developed.

The descending pain modulation system predicts short term efficacy of multimodal pain therapy - an observational prospective cohort study

OBJECTIVES

Treating chronic pain patients with multimodal pain therapy (MMPT) alters perception, awareness, and processing of pain at multiple therapeutic levels. Several clinical observations suggest that the effects of therapy may go beyond the possible sum of each level of therapy and may be due to a central descending inhibitory effect measurable by conditioned pain modulation (CPM). Thus, we investigated whether CPM is able to identify a group of patients that benefit particularly from MMPT.

METHODS

This was an observational prospective cohort study. Patients were hospitalized on a special pain medicine ward with specially trained staff for 10 days. The patients were questioned and had investigations before and shortly after MMPT and were followed-up on 3 months post discharge. Before and after treatment, subjects were investigated via CPM and quantitative sensory testing (QST) as well as completing questionnaires. The study was registered in the German Clinical Trials Register (DRKS00006850).

RESULTS

During the study period of 24 months, 224 chronic pain patients were recruited. 51 percent of patients completed the study period. There was an improvement in overall groups regarding all domains assessed, lasting beyond the end of the intervention. Patients with a sufficient CPM effect, defined as a reduction in pain during the conditioning stimulus, at baseline did show a more pronounced reduction in mean pain ratings than those without. This was not the case 3 months after therapy. Furthermore, sufficient CPM was identified as a predictor for pain reduction using a linear regression model.

CONCLUSION

In conclusion, this study shows that while a heterogeneous group of patients with chronic pain disorders does sustainably benefit from MMPT in general, patients with a sufficient CPM effect do show a more pronounced decrease in pain ratings directly after therapy in comparison to those without.

Comparative Benefit-Risk Assessment for Lidocaine 700 mg Medicated Plaster and Pregabalin in Peripheral Neuropathic Pain Following a Structured Framework Approach

Introduction

Peripheral neuropathic pain (PNP) is difficult to treat. Several oral drugs are recommended as first-line treatments. Nevertheless, many patients cannot obtain sufficient pain relief or do not tolerate systemically active treatments. Topical treatments, with a lower risk of systemic side effects such as lidocaine 700 mg medicated plaster, are also recommended in treatment guidelines. This analysis compares the benefit–risk balance of topical 700 mg lidocaine medicated plaster with the benefit–risk balance of oral pregabalin administration for the treatment of PNP following current recommendations on benefit–risk assessment (BRA) methodology.

Methods

The Benefit–Risk Action Team (BRAT) framework was used as structured approach. Selection of key benefits and risks was supported by a patient survey. Published randomized controlled clinical trials were the main source to identify data related to key benefits and risks. The outcome of randomized clinical trials was compared with real-world evidence (RWE) data for consistency.

Results

Identified key benefits were pain reduction and improvement in quality of life. Key risks identified were application site reactions, dizziness, confusion, weight gain, peripheral edema, and blurred vision. Overall, there was similarity in key benefits between the comparators; however, a clear advantage regarding key risks in favor of lidocaine 700 mg medicated plaster was observed. This observation was consistent across data from a direct comparison trial, randomized placebo-controlled trials, as well as data from RWE studies. The low number of randomized controlled trials for lidocaine 700 mg medicated plaster was the main limitation.

Conclusion

Guided by the opinion of patients regarding key benefits and risks deemed important for treatments of peripheral neuropathic pain, our analysis showed that lidocaine 700 mg medicated plaster has a more favorable benefit–risk balance compared to pregabalin (300 and 600 mg daily).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00340-2.

[Complex regional pain syndrome-An interdisciplinary view from the surgical consultation]

Chronic pain disorders are common and have a substantial impact on the patients' daily life. The specific syndrome of complex regional pain syndrome (CRPS, Sudeck's disease) is comparatively rare and characterized by additional sensorimotor, vascular and trophic dysfunctions. The diagnosis is made based on the Budapest criteria and according to clinical symptoms. According to the German national guidelines, multimodal therapy includes drug, rehabilitative and psychosomatic approaches for the reduction of pain and restoration of functionality. Bisphosphonates, steroids and antiepileptic drugs are well-established as medicinal treatment but should always be used in combination with functional therapy. Interventional treatment options are reserved for patients with complicated and enduring symptoms and should be carried out in specialized centers. The course of the disease is highly individual and frequently requires a long-term interdisciplinary treatment.

Revealing the time course of laser-evoked potential habituation by high temporal resolution analysis

BACKGROUND AND OBJECTIVES

Reduced laser-evoked potential (LEP) habituation indicates abnormal central pain processing. But the paradigm (four stimulation blocks a 25 stimuli) is time consuming and potentially omits important information on the exact habituation time course. This study examined whether a high temporal resolution (HTR) analysis (dividing the four stimulation blocks into 12 analysis blocks) can answer the following questions: (a) After how many stimuli does LEP habituation occur? (b) Is there a difference in LEP habituation in younger versus older subjects? (c) Is HTR applicable on radiculopathy patients?

METHODS

EEG data of 129 subjects were included. Thirty-four young healthy and 28 advanced-aged healthy subjects were tested with LEPs on the hand dorsum. Thirty-seven radiculopathy patients and 30 controls were tested with LEPs on the L3 dermatome. The EEG data of the hand dorsa have been analysed conventionally and with HTR analysis. The applicability of HTR has been tested on radiculopathy patients and respective controls.

RESULTS

HTR was well feasible in young healthy subjects and revealed a strong habituation effect during the first 25 stimuli (i.e. within the first 5 min). After approximately 48 stimuli, no further significant habituation was detectable. LEP amplitudes were higher in young subjects. HTR was unsuitable for elderly subjects and middle-aged radiculopathy patients.

CONCLUSIONS

In young healthy subjects, HTR allows a shortening of the test protocol while providing a detailed information on the time course of LEP habituation. A shorter protocol might be useful for the applicability of the LEP paradigm for clinical and experimental settings as well as pharmacological studies.

SIGNIFICANCE

The usage of high temporal resolution (HTR) analysis in young healthy subjects enables a short test protocol and provides the exact time course of laser-evoked potential habituation. This can be useful for the examination of neurological conditions affecting younger patients and for pharmacological studies. HTR was inapplicable in advanced-aged subjects and patients with radiculopathy.

Idiopathic Facial Pain Syndromes–An Overview and Clinical Implications

BACKGROUND

Idiopathic facial pain syndromes are relatively rare. A uniform classification system for facial pain became available only recently, and many physicians and dentists are still unfamiliar with these conditions. As a result, patients frequently do not receive appropriate treatment.

METHODS

This article is based on pertinent publications retrieved by a selective search in PubMed, focusing on current international guidelines and the International Classification of Orofacial Pain (ICOP).

RESULTS

The ICOP subdivides orofacial pain syndromes into six major groups, the first three of which consist of diseases of the teeth, the periodontium, and the temporomandibular joint. The remaining three groups (non-dental facial pain) are discussed in the present review. Attack-like facial pain syndromes most closely resemble the well-known primary headache syndromes, such as migraine, but with pain located below the orbitomeatal line. These syndromes are treated in accordance with the guidelines for the corresponding types of headache. Persistent idiopathic facial pain (PIFP) is a chronic pain disorder with persistent, undulating pain in the face and/or teeth, without any structural correlate. Since this type of pain tends to become chronified after invasive procedures, no dental procedures should be performed to treat it if the teeth are healthy; rather, the treatmentis similar to that of neuropathic pain, e.g., with antidepressant and anticonvulsive drugs. Neuropathic facial pain is also undulating and persistent. It is often described as a burning sensation, and neuralgiform attacks may additionally be present. Trigeminal neuralgia is a distinct condition involving short-lasting, lancinating pain of high intensity with a maximum duration of two minutes. The first line of treatment is with medications; invasive treatment options should be considered only if pharmacotherapy is ineffective or poorly tolerated.

CONCLUSION

With the aid of this pragmatic classification system, the clinician can distinguish persistent and attack-like primary facial pain syndromes rather easily and treat each syndrome appropriately.

Oral or Topical Pain Therapy-How Would Patients Decide? A Discrete Choice Experiment in Patients with Peripheral Neuropathic Pain

To ensure an adequate pain therapy with high patient adherence, it is necessary to know and consider patient preferences. A discrete choice experiment was used to obtain patients' preferences regarding treatment with systemic or topical pain medication. Patients with peripheral neuropathic pain (pNP) were recruited in two pain-focused practices in Germany. To identify relevant attributes of topical or systemic pain medication, a literature review and face-to-face interviews with experts for pain treatment were conducted. The attributes used in the choice scenarios were noticeable onset of effect, time spent in medical office, risk of systemic and local side effects, and impairment of daily life with regard to sleep quality and sexuality. The model was estimated with a mixed multinomial logit regression model. The study included 153 participants suffering from moderate to severe pNP. Most important attributes from patient's perspective was noticeable onset of effect (odds ratio 2.141 [95% confidence interval 1.837 to 2.494]), followed by risk of systemic side effects (2.038 [1.731 to 2.400]) and risk of sexual dysfunction (1.839 [1.580 to 2.140]), while risk of local side effects regarding skin ranked fourth (1.612 [1.321 to 1.966]). The impairment of sleep quality was also significant but less important (1.556 [1.346 to 1.798]). Local side effects were more likely to be accepted than systemic side effects. The risk of sexual dysfunction as a side effect of treatment is very important for patients, although it has received little attention in the literature.