[Retrospective evaluation of electronically recorded patient questionnaires of a university outpatient pain clinic with the painDETECT® questionnaire]

BACKGROUND AND OBJECTIVE

Psychometric tests can provide important information for diagnostics and progression in chronic pain patients. Between 2008 and 2018, the electronic system painDETECT® was used in the outpatient pain clinic of the Hannover Medical School (MHH). The aim of this retrospective study was to evaluate the pain symptomatology data recorded using painDETECT® and the treatment procedures used in the patient cohort examined over a period of 15 months.

MATERIAL AND METHODS

A statistical analysis of baseline and follow-up data was performed. The analysis comprised pain-related parameters recorded by use of the painDETECT® system as well as outpatient records.

RESULTS

Baseline data of 459 patients (66% women) could be evaluated. The most common clinical pictures were spinal pain, headache, facial pain, and somatoform disorders, mostly with many years of previous treatment. Approximately 40% showed evidence of neuropathic pain components or central sensitization. With a mean pain intensity of VAS 6 (0-10), a predominantly high degree of chronicity was present. Approximately one third showed a high degree of pain-related functional impairment. Slightly more than half showed evidence of clinically relevant depression. Approximately 80% showed clinically relevant sleep disturbances. Follow-up data were available for 145 patients (31.6%). The proportion of patients receiving a nonpharmacological form of treatment increased by 44.1% (physical therapy) and by 24.1% (psychotherapeutic procedures) during the observation period. The use of co-analgesics increased by approximately 30% over the course.

CONCLUSION

In the outpatient setting, an extension of treatment can be successful for high-grade chronic pain patients. Close structural networking with the clinics for rehabilitation medicine and for psychosomatics and psychotherapy at the MHH can be a favorable prerequisite for this.

Overview: Chronic Pain and Cannabis-Based Medicines

Chronic pain is primarily conceptualized as a disease in its own right when it is associated with emotional distress and functional impairment. Pathophysiologically, dysfunction of the cortico-mesolimbic connectome is of major importance, with overlapping signals in the nociceptive and stress systems. The endocannabinoid system plays an important role in the central processing of nociceptive signals and regulates the central stress response. Clinically, there is moderate evidence that cannabis-based medicines (CBM) can contribute to a significant reduction in pain, especially the associated pain affect, and improvement in physical function and sleep quality in a proportion of patients with chronic pain. The analgesic effect appears to be largely independent of the cause of pain. In this context, CBM preferentially regulates stress-associated pain processing.

Effects on temporomandibular disorder in the treatment of tension-type headache with acupuncture and therapeutic exercises. A secondary analysis from a randomized controlled trial

OBJECTIVES

To examine the effects of acupuncture and therapeutic exercise alone and in combination on temporomandibular joint symptoms in tension-type headache and to evaluate the potential interaction of existing temporomandibular dysfunction on the success of headache treatment.

DESIGN

Pre-planned secondary analysis of a randomized controlled, non-blinded trial.

SETTING

Outpatient clinic of a German university hospital.

SUBJECTS

Ninety-six Participants with frequent episodic or chronic tension-type headache were randomized to one of four treatment groups.

INTERVENTIONS

Six weeks of acupuncture or therapeutic exercise either as monotherapies or in combination, or usual care. Follow-up at 3 and 6 months.

MAIN MEASURES

Subjective temporomandibular dysfunction symptoms were measured using the Functional Questionnaire Masticatory Organ, and the influence of this sum score and objective initial dental examination on the efficacy of headache treatment interventions was analyzed.

RESULTS

Temporomandibular dysfunction score improved in all intervention groups at 3-month follow-up (usual care: 0.05 [SD 1.435]; acupuncture: -5 [SD 1.436]; therapeutic exercise: -4 [SD 1.798]; combination: -3 [SD 1.504]; P = 0.03). After 6 months, only acupuncture (-6 [SD 1.736]) showed a significant improvement compared to the usual care group (P < 0.01). Subjective temporomandibular dysfunction symptoms had no overall influence on headache treatment.

CONCLUSIONS

Only acupuncture had long-lasting positive effects on the symptoms of temporomandibular dysfunction. Significant dental findings seem to inhibit the efficacy of acupuncture for tension-type headache.

Clinical characterisation of women with persistent genital arousal disorder: the iPGAD-study

Persistent Genital Arousal Disorder (PGAD) is a rare condition-mostly in women-where patients perceive prolonged genital arousal without any sexual desire or stimulation. Etiopathological considerations reach from peripheral to central issues over local disturbance of the pudendal nerve to neuropathy, psychosocial, and pharmacological theories. Since well controlled clinical studies about PGAD in conjunction with a mental and somatic health status are missing, this study is a detailed clinical investigation of PGAD patients compared to healthy controls. 26 women who fulfilled diagnostic criteria for PGAD were compared to 26 age matched healthy controls. Investigations included comparison of vegetative, gynaecological and sexual history, psychiatric features as well as a (neuro-)radiological, neurophysiological and gynaecological examination. Moreover, a detailed clinical characterisation of PGAD symptoms was performed. PGAD symptoms were mostly characterised as tingling or prickling and were permanently present. In over 80%, PGAD symptoms were located in the clitoris. Almost 70% reported radiations to other regions of the body. Most frequent trigger factors were tight clothes, mental stress, driving a car/bus/bicycle and sexual intercourse. Relieving factors were mainly distraction, relaxation, physical exercise, masturbation and swimming. In group comparisons, PGAD presented with significant higher rates of sexual dysfunctions, spontaneous orgasms, swelling of the genitals, extraordinary lubrication as well as higher rates in depression, agoraphobia, generalized anxiety disorder and lifetime panic disorder. Significantly more PGAD patients were diagnosed with restless legs symptoms. In contrast childhood traumatization, somatization disorder, suicidality, gynaecological as well as neurophysiological examination of the pudendal nerve were not different between the groups. MRI of the brain, pelvis and spinal cord was unsuspicious and incidental findings - including Tarlov cysts or pelvic venous congestion - were equally distributed among the groups. In summary, our study provides a careful characterization of women with PGAD highlighting a serious mental burden, most probably as a consequence of PGAD. With the current set of clinical investigations there was no evidence of a clear causal relationship to a specific clinical finding as it has been previously discussed. Future studies and additional techniques will have to further explore where and how in the peripheral or central nervous systems PGAD develops.

Patients' perspectives on prescription cannabinoid therapies: a cross-sectional, exploratory, anonymous, one-time web-based survey among German patients

Introduction

Since cannabinoids were partially legalized as prescription medicines in Germany in 2017, they are mostly used when conventional therapies do not suffice. Ambiguities remain regarding use, benefits and risks. This web-based survey explored the perspectives of patients whose experiences are not well enough known to date.

Methods

In an anonymous, exploratory, cross-sectional, one-time web-based observational study, participants receiving cannabinoid therapy on prescription documented aspects of their medical history, diagnoses, attitudes toward cannabinoids, physical symptoms, and emotional states. Participants completed the questionnaires twice here: first regarding the time of the survey and then, retrospectively, for the time before their cannabinoid therapy. Participants were recruited in a stratified manner in three German federal states.

Results

N = 216 participants (48.1% female, aged 51.8 ± 14.0) completed the survey, most of which (72%, n = 155) reported pain as their main reason for cannabinoid therapy. When comparing the current state with the retrospectively assessed state, participants reported greater satisfaction with their overall medical therapy (TSQM II: +47.9 ± 36.5, p < 0.001); improved well-being (WHO-5: +7.8 ± 5.9, p < 0.001) and fewer problems in PROMIS subscales (all p < 0.001). Patients suffering primarily from pain (72%, n = 155) reported a reduction of daily pain (NRS: -3.2 ± 2.0, p < 0.001), while participants suffering mainly from spasticity (8%, n = 17) stated decreased muscle spasticity (MSSS: -1.5 ± 0.6, p < 0.001) and better physical mobility (-0.8 ± 0.8, p < 0.001). Data suggests clinically relevant effects for most scores. Participants' attitudes toward cannabinoids (on a 5-point scale) improved (+1.1 ± 1.1, p < 0.001). Most patients (n = 146, 69%) did not report major difficulties with the cannabinoid prescription process, while (n = 27; 19%) had their cannabinoid therapy changed due to side effects.

Discussion

Most participants experienced their therapy with cannabinoids as more effective than their previous therapy. There are extensive limitations to this cross-sectional study: the originally intended representativeness of the dataset was not reached, partly due to the SARS-CoV-2 pandemic; the sample has a larger proportion of privately insured and self-paying patients. Results does not suggest that cannabinoid patients belong to a particular clientele. Effect sizes observed for pain reduction, quality of life, social participation, and other outcomes suggest a therapeutic potential, particularly in the treatment of chronic pain.

EMG measured reaction time as a predictor of invalid symptom report in psychosomatic patients

Background: Symptom validity tests (SVTs) and performance validity tests (PVTs) are important tools in sociomedical assessments, especially in the psychosomatic context where diagnoses mainly depend on clinical observation and self-report measures. This study examined the relationship between reaction times (RTs) and scores on the Structured Inventory of Malingered Symptomatology (SIMS). It was proposed that slower RTs and larger standard deviations of reaction times (RTSDs) would be observed in participants who scored above the SIMS cut-off (>16). Methods: Direct surface electromyography (EMG) was used to capture RTs during a computer-based RT test in 152 inpatients from a psychosomatic rehabilitation clinic in Germany. Correlation analyses and Mann-Whitney U were used to examine the relationship between RTs and SIMS scores and to assess the potential impact of covariates such as demographics, medical history, and vocational challenges on RTs. Therefore, dichotomized groups based on each potential covariate were compared. Results: Significantly longer RTs and larger RTSDs were found in participants who scored above the SIMS cut-off. Current treatment with psychopharmacological medication, diagnosis of depression, and age had no significant influence on the RT measures. However, work-related problems had a significant impact on RTSDs. Conclusion: There was a significant relationship between longer and more inconsistent RTs and indicators of exaggerated or feigned symptom report on the SIMS in psychosomatic rehabilitation inpatients. Findings from this study provide a basis for future research developing a new RT-based PVT.

Therapeutic Use of Cannabinoids in Critically Ill Patients: A Survey of Intensive Care Physicians in Germany

Background: In the course of the legalization of cannabis for therapeutic purposes in Germany, there has been growing interest in the medical use of cannabinoids. To date, the therapeutic potential of cannabinoids for the treatment of critically ill patients has not been explored. Objectives: This study aims to understand better whether and how frequently cannabinoids have been administered to critically ill patients in recent years. Study Design: Initially, a survey was conducted among physicians working in intensive care units (ICUs) at the Hannover Medical School. Subsequently, 653 physicians working in ICUs throughout Germany were surveyed. The frequency and regimen of cannabinoid therapy initiated by the participating physicians in the last 2 years at the time of the survey were characterized. Results: Eight out of 9 physicians at Hannover Medical School and 59 out of 653 physicians in ICUs in Germany participated. At Hannover Medical School, 6 out of 8 physicians and in ICUs in Germany, 16 out of 59 physicians had used cannabinoids in some patients (mainly 9-10) during the 2-year period studied, with dronabinol in doses between 1 and 20 mg being their cannabinoid of choice. Metabolic and psychological distress and medication savings, followed by pain and nausea/vomiting, were the most frequently cited indications for cannabinoid therapy. No relevant safety issues arrived. Lack of personal experience, limited evidence, and gaps in knowledge were the most commonly cited reservations about cannabinoid use. Conclusions: During a 2-year period, dronabinol is used in a few critically ill patients in ICUs. The main indications are to reduce metabolic and psychological distress and to save medication. The majority of participating physicians indicated that the use of cannabinoids in the context of critical care medicine needs further exploration.

Traumatic Events, Posttraumatic Stress Disorder, and Central Sensitization in Chronic Pain Patients of a German University Outpatient Pain Clinic

OBJECTIVE

Posttraumatic stress disorder (PTSD) and traumatic life events are often coupled to chronic pain, possibly linked by central sensitization. We wanted to assess the prevalence of traumatic events and PTSD in chronic pain patients of a German university hospital outpatient pain clinic. Moreover, we evaluated the extent of indicators and co-occurring traits of central sensitization in comorbid patients.

METHODS

We retrospectively divided 914 chronic pain patients into four groups depending on their trauma severity: no trauma, accidental trauma, interpersonal trauma, and PTSD. We collected electronic pain drawings focusing on pain area and widespreadness, as well as information about pain intensity, sleep impairment, disability, stress, anxiety, depression, and somatization. Differences between groups were calculated using Kruskal-Wallis with post-hoc Mann-Whitney tests.

RESULTS

Of 914 patients, 231 (25%) had no trauma, 210 (23%) had accidental traumas, 283 (31%) had interpersonal traumas, 99 (11%) had PTSD, and 91 (10%) could not be classified. We observed statistically significant differences between groups in pain area and widespreadness, as well as maximal pain, sleep impairment, disability, stress, anxiety, depression, and somatization. The severity of symptoms increased with trauma severity.

CONCLUSIONS

Traumatic life events and PTSD are frequent in chronic pain patients. The increased pain area and widespreadness, as well as the increased negative impact on co-occurring traits of sensory sensitivity (anxiety, depression, somatization), are compatible with central sensitization in comorbid patients. Therefore, a heightened awareness of the comorbidity between traumatic experiences and chronic pain is recommended.

Patient Experiences With Prescription Cannabinoids in Germany: Protocol for a Mixed Methods, Exploratory, and Anonymous Web-Based Survey

BACKGROUND

Medical cannabinoids are controversial. Their use is comparatively rare, but it is rising. Since 2017, cannabinoids can be prescribed in Germany for a broader range of indications. Patient surveys on these drugs are hampered by the stigmatization of cannabinoids and their (still) low prevalence in medical contexts. Against this background, patients' willingness to provide information is limited. Moreover, it is logistically challenging to reach them with a survey. A thorough knowledge of currently ongoing therapies and their effects and side effects, however, is important for a more appropriate and effective use of cannabinoids in the future.

OBJECTIVE

This study is an exploratory data collection using a representative sample. The main goal is to provide a detailed picture of the current use of medical cannabinoids in Germany. It is intended to identify subgroups that may benefit particularly well or poorly.

METHODS

We are conducting a representative, anonymous, cross-sectional, one-time, web-based survey based on mixed methods in 3 German federal states. Health conditions under cannabinoid therapy and before are documented with validated, symptom-specific questionnaires. This allows an estimation of the effect sizes of these therapies. The selection of parameters and questionnaires was based on the results of independent qualitative interviews in advance. Representative samples of the hard-to-reach study population are obtained by cluster sampling via contracted physicians of the statutory health insurance companies.

RESULTS

Recruitment was ongoing until the end of June 2022, with 256 enrolled participants. Validated questionnaires on pain, spasticity, anorexia or wasting, multiple sclerosis, nausea or vomiting, depression, and attention deficit hyperactivity disorder (ADHD) were selected. Symptom scores are being assessed for both current conditions under cannabinoid therapy and conditions prior to this therapy (in retrospect). Validated questionnaires are also used for treatment satisfaction and general quality of life. These are supplemented by existing diagnoses, a detailed medication history, any previous experiences with cannabis or illegal substances, experiences with the prescription process, and sociodemographic data. Based on the results of the previous qualitative interviews, questions were added regarding prior experience with relaxation methods and psychotherapy, personal opinions about cannabinoids, pre-existing or symptom-related psychological trauma, and different experiences with different cannabis-based therapies.

CONCLUSIONS

The exploratory mixed methods approach of this project is expected to provide valid and relevant data as a basis for future clinical research. The study design may be representative for a large proportion of outpatients treated with cannabinoids in the German federal states studied. It may have less bias toward social desirability and may provide valuable information in addition to existing studies. Due to the observational and cross-sectional nature of this study, various limitations apply. Causal relations cannot be drawn.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00023344; https://drks.de/search/en/trial/DRKS00023344.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/38814.

Effects of acupuncture and medical training therapy on depression, anxiety, and quality of life in patients with frequent tension-type headache: A randomized controlled study

OBJECTIVES

To compare the effects of acupuncture and medical training therapy in combination or individually with usual care on quality of life, depression, and anxiety in patients with tension-type headache.

METHODS

In this single-center, prospective, randomized, controlled, unblinded trial, 96 adults (38.7(+/-13.3) years of age; 75 females/20 males/one dropout) with frequent episodic or chronic tension-type headache were randomized to one of four treatment groups (n = 24). The treatment groups received six weeks of either acupuncture or medical training therapy as monotherapies or in combination (12 interventions each), or usual care. We assessed depressiveness (PHQ-9), anxiety (GAD-7), and health-related quality of life (SF-12) as secondary outcome parameters at baseline, six weeks, three months, and six months after initiation of treatment. Linear mixed models were calculated.

RESULTS

Both, acupuncture (baseline to six-weeks change scores: mean: -2(standard deviation: 2.5 points), three months: -2.4(2.4), six-months -2.7(3.6)) and the combination of acupuncture and medical training therapy (-2.7(4.9), -2.2(4.0), -2.2(4.2)) (each within-group p < .05) significantly reduced depressiveness-scores (PHQ-9) to a greater extent than medical training therapy (-0.3(2.0), -0.5(1.6), -0.9(2.6)) or usual care alone (-0.8(2.9), 0.1(2.8), 0.2(3.6)). We found similar results with anxiety scores and the physical sum scores of the SF-12. No severe adverse events occurred.

CONCLUSIONS

Acupuncture and the combination of acupuncture and medical training therapy elicit positive effects on depression, anxiety, quality of life, and symptom intensity in patients with episodic and chronic tension-type headache. Acupuncture appears to play a central role in mediating the therapeutic effects, underscoring the clinical relevance of this treatment. An additive benefit of the combination of both therapies does not appear to be relevant.Trial registration: Registered on 11 February 2019. German Clinical Trials Register, DRKS00016723.

Neuronal effects of glabellar botulinum toxin injections using a valenced inhibition task in borderline personality disorder

Previous studies have indicated that glabellar botulinum toxin (BTX) injections may lead to a sustained alleviation of depression. This may be accomplished by the disruption of a facial feedback loop, which potentially mitigates the experience of negative emotions. Accordingly, glabellar BTX injection can attenuate amygdala activity in response to emotional stimuli. A prototypic condition with an excess of negative emotionality and impulsivity accompanied by elevated amygdala reactivity to emotional stimuli is borderline personality disorder (BPD). In order to improve the understanding of how glabellar BTX may affect the processing of emotional stimuli and impulsivity, we conducted a functional magnetic resonance imaging (fMRI) study. Our hypotheses were (1) glabellar BTX leads to increased activation in prefrontal areas during inhibition performance and (2) BTX decreases amygdala activity during the processing of emotional stimuli in general. Using an emotional go-/no-go paradigm during fMRI, the interference of emotion processing and impulsivity in a sample of n = 45 women with BPD was assessed. Subjects were randomly assigned to BTX treatment or serial acupuncture (ACU) of the head. After 4 weeks, both treatments led to a reduction in the symptoms of BPD. However, BTX treatment was specifically associated with improved inhibition performance and increased activity in the motor cortex. In addition, the processing of negative emotional faces was accompanied by a reduction in right amygdala activity. This study provides the first evidence that glabellar BTX injections may modify central neurobiological and behavioural aspects of BPD. Since the control treatment produced similar clinical effects, these neurobiological findings may be specific to BTX and not a general correlate of symptomatic improvement.

The interplay of chronic stress and genetic traits discriminates between patients suffering from multisomatoform disorder with pain as the leading symptom and matched controls

OBJECTIVE

Somatoform disorders and functional somatic syndromes (FSS) with symptoms that are not sufficiently explained by physical or technical examination are among the most challenging underlying causes. Many different somatoform disorders and FSS have overlapping symptoms, often with pain as the most prevalent one, leading to a high burden of disease. The concept of multisomatoform disorder (MSD) has been developed to acknowledge that fact. We analyzed a group of 151 patients and 149 matched controls to identify interactions of genetic and environmental factors with a possible influence on the development of MSD.

DESIGN

In a retrospective case-control study, we performed a statistical analysis on 151 patients and 149 matched controls using logistic regression and a Classification and Regression Tree (CART) analysis.

RESULTS

The logistic regression analysis of genes and environmental factors demonstrated significant differences in the results of the Trier Inventory of Chronic Stress (TICS) questionnaire, the single nucleotide polymorphism rs1800955 of the dopamine receptor D4 and the single nucleotide polymorphism rs4818 of the enzyme catechol-O-methyltransferase between patients with MSD and healthy controls. The resulting decision tree of the CART analysis determined that the TICS questionnaire was able to differentiate patients and controls most accurately, followed by certain genotypes of the 5-hydroxytryptamine receptor 2A and a single nucleotide polymorphism of the enzyme catechol-O-methyltransferase.

CONCLUSIONS

The results of the statistical analysis identified a gene-environmental interaction possibly leading to MSD. The resulting identifiers could be used as a reference to inform diagnostic algorithms to easier identify patients suffering from MSD.

Clinical effects of glabellar botulinum toxin injections on borderline personality disorder: A randomized controlled trial

BACKGROUND

Inhibition of frowning via injections of botulinum toxin A (BTX) into the glabellar region has shown beneficial effects in the treatment of major depression. Preliminary research suggests that improvements in the affective domain are not depression-specific, but may also translate to other psychiatric disorders.

AIM

This 16-week, single-blind, two-center randomized controlled trial investigated the influence of BTX on clinical symptoms of borderline personality disorder (BPD).

METHODS

Fifty-four patients with BPD were randomly assigned to treatment with BTX (n = 27) or a minimal acupuncture (ACU) control condition (n = 27). Clinical outcomes were followed at 2, 4, 6, 8, 12, and 16 weeks. Primary endpoint was the relative score change on the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) 8 weeks after baseline relative to the control group and adjusted for treatment center. Secondary and additional outcome variables were self-rated borderline symptoms, comorbid symptoms of depression, psychological distress, and clinical global impression.

RESULTS

Participants showed significant improvements at the primary efficacy endpoint in both treatment groups (BTX: M = -0.39, SD = 0.39; ACU: M = -0.35, SD = 0.42), but no superior effect of the BTX condition in comparison with the control intervention was found-F(1,5323) = 0.017, p = 0.68). None of the secondary or additional outcomes yielded significant group differences. Side effects were mild and included headache, transient skin or muscle irritations, and dizziness.

CONCLUSION

Evidence regarding the efficacy of BTX for BDP remains limited, and the design of adequate control conditions presents an opportunity for further research.ClinicalTrials.gov registry: Botulinum Toxin A for Emotional Stabilization in Borderline Personality Disorder (BPD), NCT02728778, https://clinicaltrials.gov/ct2/show/NCT02728778.

Combination of acupuncture and medical training therapy on tension type headache: Results of a randomised controlled pilot study

OBJECTIVES

The aim of this study was to compare the effects of acupuncture and medical training therapy alone and in combination with those of usual care on the pain sensation of patients with frequent episodic and chronic tension-type headache.

DESIGN

This was a prospective single-centre randomised controlled trial with four balanced treatment arms. The allocation was carried out by pre-generated randomisation lists in the ratio 1:1:1:1 with different permutation block sizes.

SETTING

The study was undertaken in the outpatient clinic of Rehabilitation Medicine of the Hannover Medical School.Participants and interventions: Ninety-six adult patients with tension-type headache were included and randomised into usual care (n = 24), acupuncture (n = 24), medical training (n = 24), and combination of acupuncture and medical training (n = 24). One patient was excluded from analysis because of withdrawing her/his consent, leaving 95 patients for intention to treat analysis. Each therapy arm consisted of 6 weeks of treatment with 12 interventions. Follow-up was at 3 and 6 months.

MAIN OUTCOME MEASURES

Pain intensity (average, maximum and minimum), frequency of headache, responder rate (50% frequency reduction), duration of headache and use of headache medication.Clinical results: The combination of acupuncture and medical training therapy significantly reduced mean pain intensity compared to usual care (mean = -38%, standard deviation = 25%, p = 0.012). Comparable reductions were observed for maximal pain intensity (-25%, standard deviation = 20%, 0.014) and for minimal pain intensity (-35%, standard deviation = 31%, 0.03). In contrast, neither acupuncture nor medical training therapy differed significantly from usual care. No between-group differences were found in headache frequency, mean duration of headache episodes, and pain medication intake. At 3 months, the majority of all patients showed a reduction of at least 50% in headache frequency. At 6 months, significantly higher responder rates were found in all intervention groups compared to usual care.

CONCLUSIONS

In contrast to monotherapy, only the combination of acupuncture and medical training therapy was significantly superior in reduction of pain intensity compared to usual care.Trial registration: Registered on 11 February 2019. German Clinical Trials Register, DRKS00016723.

Flotation Restricted Environmental Stimulation Therapy for Chronic Pain: A Randomized Clinical Trial

IMPORTANCE

Flotation restricted environmental stimulation therapy (REST) is an emerging therapeutic intervention that, to our knowledge, has never been directly compared with an indistinguishable placebo in patients with chronic pain.

OBJECTIVE

To determine whether 5 flotation-REST sessions alleviate chronic pain.

DESIGN, SETTING, AND PARTICIPANTS

This single-blind, randomized clinical trial compared flotation-REST as an intervention for the treatment of chronic pain with indistinguishable placebo and wait-list control conditions at Hannover Medical School, Hannover, Germany. Men and women aged 18 to 75 years who had been diagnosed with chronic pain disorder with psychological and somatic factors (International Statistical Classification of Diseases and Related Health Problems, 10th Revision, German Modification, code F45.41) by physicians at the study center were randomly assigned to 1 of the 3 groups. Data were collected from June 26, 2018, to June 18, 2020.

INTERVENTIONS

Patients in the intervention and placebo groups underwent 5 treatment sessions lasting 60 to 90 minutes, each session separated by 4 days. The placebo treatment was delivered in the same floating tank but controlled for effortless floating and environmental stimulus restriction. Patients in the wait-list control group did not receive any additional treatment but were asked to continue any ongoing treatments at the time of enrollment.

MAIN OUTCOMES AND MEASURES

The primary outcome was a change in pain intensity 1 week after the last treatment session. The assessment was repeated at 12 and 24 weeks. Secondary outcomes included pain-related disability, pain area, pain widespreadness (number of body regions affected by pain), anxiety, depression, and quality of life, as well as several other short-term outcomes.

RESULTS

A total of 99 patients (mean [SD] age, 51.7 [12.3] years; 80 women [81%]) were included in the study. No differences were found among the groups in the primary outcomes (mean [SD] change in maximum pain: -7.6 [19.7] for the intervention group, -5.8 [12.7] for the placebo group, and 0.4 [14.0] for the wait-list control group; mean [SD] change in mean pain: -2.1 [19.4] for the intervention group,-4.2 [16.2] for the placebo group, and 2.0 [12.6] for the wait-list control group). Long-term secondary outcomes did not show significant differences. In the short term, patients in the intervention group showed significant improvements in pain intensity (-17.0 [17.1]; P < .001), relaxation (23.9 [22.6]; P < .001), anxiety (-10.1 [8.4]; P < .001), pain area (-3.6% [7.4%]; P < .001), and widespreadness (-2.0 [3.0]; P < .001), and similar changes where observed in the placebo group.

CONCLUSIONS AND RELEVANCE

Patients with chronic pain experienced no long-term benefits from the 5 flotation-REST interventions. Clinically relevant short-term changes in pain in the placebo group suggest that improvements may not be caused by environmental stimulus restriction or effortless floating as previously thought.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03584750.

[Evaluation of outpatient medical pain management in Germany : Results of an internet-based cross-sectional survey among pain specialists in outpatient departments]

Hintergrund

Nach den Kriterien der Qualitätssicherungsvereinbarung Schmerztherapie (QSV) nahmen zum Stichtag 31.12.2016 1206 Ärztinnen und Ärzte an der ambulanten Versorgung chronischer Schmerzpatienten teil. Bei in weiten Teilen bestehender Unterversorgung chronischer Schmerzpatienten fehlen Daten zur Einschätzung der ambulanten Schmerztherapie durch die Schmerztherapeuten selbst.

Methoden

In einem Hybrid-Delphi-Verfahren wurde ein Fragebogen zur inhaltlichen, strukturellen und persönlichen Bewertung der ambulanten Schmerztherapie in Deutschland entwickelt.

Mit diesem Instrument wurde eine internetbasierte Querschnittsbefragung von 281 QSV-Schmerzmedizinern aus vier Bundesländern (Berlin, Niedersachsen, Sachsen, Baden-Württemberg) und aller universitären Schmerzambulanzleiter (n = 36) in Deutschland durchgeführt.

Ergebnisse

Die Befragung erzielte eine bereinigte Rücklaufquote von insgesamt 35,9 %. Bei den Schmerzambulanzleitern antworteten 66,7 %. Bei 91 % der Befragten lag der Anteil an chronisch Schmerzkranken in der Praxis bei über 70 %. 67,3 % geben an, mit ihrer Praxissituation zufrieden zu sein, auf der anderen Seite äußern 63,4 % ihre Unzufriedenheit mit der aktuellen Organisation der Schmerzmedizin in Deutschland insgesamt. Diese Unzufriedenheit zeigt sich vor allem in Bezug auf die Budgetregelungen (69,3 %), die Kooperation mit Psychotherapeuten (69,3 %) und die interdisziplinäre Vernetzung (50,5 %). Als gute Vorbereitung für den späteren Beruf werden die einjährige Weiterbildung bei einem Weiterbildungsbefugten (87,1 %) und die Teilnahme an dem Kurs „Psychosomatische Grundversorgung“ (90,1 %) bewertet. Vielfältige Freitextkommentare weisen darauf hin, dass die Ausbildung zu kurz und nicht ausreichend sei. Die Mehrheit der Befragten hält es sowohl aus Arztsicht (61,4 %) wie auch aus Patientensicht (54,5 %) für sinnvoll, einen Facharzt für Schmerzmedizin als Versorgungsmodell zu etablieren. 70,8 % der Schmerzambulanzleiter sprechen sich für eigenständige Strukturen mit eigenem Budget aus, 75,0 % geben an, dass ihre Ambulanz unter den aktuellen Bedingungen nicht kostendeckend arbeitet. In Bezug auf die aktuelle Ausbildungssituation berichten nur 39,7 % der QSV-Schmerztherapeuten in der Niederlassung, dass sie auch Ärzte ausbilden, 57,6 % von ihnen planen zudem, ihre Tätigkeit innerhalb der nächsten 10 Jahre aufzugeben.

Schlussfolgerungen

Die mangelnde Eigenständigkeit der Schmerzmedizin und die unzureichend ausgebauten ambulanten Versorgungsnetzwerke tragen dazu bei, dass Schmerztherapeuten mit vielen Aspekten ihrer Tätigkeit unzufrieden sind. Die Etablierung eines Facharztes für Schmerztherapie wird als eine gute Lösung für eine bessere schmerzmedizinische Versorgung und für die Nachwuchsproblematik gesehen.

Comparative effects of (S)-ketamine and racemic (R/S)-ketamine on psychopathology, state of consciousness and neurocognitive performance in healthy volunteers

Ketamine and its (S)-enantiomer show distinct psychological effects that are investigated in psychiatric research. Its antidepressant activity may depend on the extent and quality of these psychological effects which may greatly differ between the enantiomers. Previous data indicate that the (S)-ketamine isomer is a more potent anesthetic than (R)-ketamine. In contrast, in subanesthetic doses (R)-ketamine seems to elicit fewer dissociative and psychotomimetic effects compared to (S)-ketamine. In this randomized double-blind placebo-controlled trial the effects of (R/S)-ketamine and (S)-ketamine on standardized neuropsychological and psychopathological measures were compared. After an initial bolus equipotent subanesthetic doses of (R/S)- and (S)-ketamine or placebo were given by continuous intravenous infusion to three groups of 10 healthy male volunteers each (n = 30). (R/S)-Ketamine and (S)-ketamine produced significant psychopathology and neurocognitive impairment compared to placebo. No significant differences were found between (R/S)-ketamine and (S)-ketamine. (S)-Ketamine administration did not result in reduced psychopathological symptomatology compared to (R/S)-ketamine as suggested by previous studies. However, this study revealed a somewhat more "negatively experienced" psychopathology with (S)-ketamine, which opens questions about potential "protective effects" associated with the (R)-enantiomer against some psychotomimetic effects induced by the (S)-enantiomer. As the antidepressant effect of ketamine might depend on a pleasant experience of altered consciousness and perceptions and avoidance of anxiety, the ideal ketamine composition to treat depression should include (R)-ketamine. Moreover, since preclinical data indicate that (R)-ketamine is a more potent and longer acting antidepressant compared to (S)-ketamine and (R/S)-ketamine, randomized controlled trials on (R)-ketamine and comparative studies with (S)-ketamine and (R/S)-ketamine are eagerly awaited.

Autoantibodies against P29ING4 are associated with complex regional pain syndrome

INTRODUCTION

Complex regional pain syndrome (CRPS) is a complication following trauma or surgery and may be difficult to diagnose since biomarkers are lacking. Using protein array technology, we found antibodies binding to p29ING4, which we further characterized using ELISA.

METHODS

Thirty-six sera of early-stage type 1 CRPS, 66 sera of rheumatoid arthritis (RA), 53 sera of axial spondyloarthritis (axSpA), 29 sera of psoriatic arthritis (PsA), 22 sera of patients after radial fractures (trauma control), and 100 sera of blood donors (BD) were analyzed for anti-p29ING4. We established ELISAs with 7 different antigens and using different secondary antibodies binding to IgG, IgG1, IgG2, IgG3, IgG4, IgA, and IgM, and 2 different tests to detect immune complexes (IC) of p29ING4 and IgG or IgG1.

RESULTS

The highest likelihood ratios versus CRPS and trauma control were observed considering the A1-23 (sensitivity 19%, specificity 100%, LR > 19) using IgG as a secondary antibody, the A120-165 (sensitivity 17%, specificity 100%, LR = 17) using IgG as a secondary antibody and the A120-165 (sensitivity 31%, specificity 95%, LR = 6.2) using IgA as a secondary antibody. IC of p29ING4 and IgG were present in 11/36 (31%) CRPS sera, 17/64 (27%) RA sera, 13/53 (25%) SpA sera, 5/29 (17%) PsA sera, 1/22 (5%) trauma control sera, and 4/100 (4%) sera of BD. IC of p29ING4 and IgG1 were present in 14/36 (39%) CRPS sera, 19/64 (30%) RA sera, 13/53 (25%) SpA, 1/29 (3%) PsA, 2/22 (9%) trauma control, and 4/100 (4%) of the BD sera.

CONCLUSION

Due to the lack of other biomarkers of type 1 CRPS, P29ING4 autoantibodies could be helpful in its diagnostic work-up.

Quantitative Sensory Testing in Patients with Multisomatoform Disorder with Chronic Pain as the Leading Bodily Symptom-a Matched Case-Control Study

OBJECTIVE

Chronic pain is a debilitating condition of multifactorial origin, often without physical findings to explain the presenting symptoms. Of the possible etiologies of persisting painful symptoms, somatoform disorders and functional somatic syndromes (FSS) are among the most challenging, with a prevalence of 8-20%. Many different somatoform disorders and FSS have overlapping symptoms, with pain being the most prevalent one. The concept of multisomatoform disorder (MSD) has been developed to acknowledge that fact. We hypothesized that the concept of MSD will be reflected in a distinct sensory profile of patients compared with healthy controls and possibly provide insight into the type and pathophysiology of the pain commonly experienced by patients.

DESIGN

We performed comprehensive quantitative sensory testing (QST) in 151 patients and 149 matched controls.

RESULTS

There were significant differences in the sensory profiles of patients compared with controls. Patients with MSD showed a combination of tactile and thermal hypesthesia combined with mechanical and cold hyperalgesia. This was true for measurements at test and control sites, with the exception of vibration detection threshold and mechanical pain threshold. Among the observed changes, a marked sensory loss of function, as evidenced by an increase in cold detection threshold, and a marked gain of function, as evidenced by a decrease of pressure pain threshold, were most notable. There was no evidence of concurrent medication influencing QST results.

CONCLUSIONS

The observed somatosensory profile of patients with MSD resembles that of patients suffering from neuropathic pain with evidence of central sensitization.

The best from East and West? Acupuncture and medical training therapy as monotherapies or in combination for adult patients with episodic and chronic tension-type headache: study protocol for a randomized controlled trial

BACKGROUND

This study aims to evaluate the feasibility and efficacy of a complex health intervention, based on the combination of conventional Western medicine and traditional Chinese medicine (TCM), in an outpatient department of a university hospital for patients with frequent episodic or chronic tension-type headaches.

METHODS/DESIGN

This is a prospective randomized controlled pilot study with four balanced treatment arms (usual care, acupuncture, training, and training plus acupuncture). Each arm will have 24 patients. After the initial screening examination and randomization, a 6-week treatment period follows, with treatment frequencies decreasing at 2-week intervals. After completion of the intervention, two follow-up evaluations will be performed 3 and 6 months after the start of treatment. At predefined times, the various outcomes (pain intensity, health-related quality of life, pain duration, autonomic regulation, and heart rate variability) as well as the participants' acceptance of the complex treatment will be evaluated with valid assessment instruments (Migraine Disability Assessment, PHQ-D, GAD-7, and SF-12) and a headache diary. The acupuncture treatment will be based on the rules of TCM, comprising a standardized combination of acupuncture points and additional points selected according to individual pain localization. The training therapy comprises a combination of strength training, endurance training, and training to improve flexibility and coordination. Besides descriptive analyses of the samples, their comparability will be assessed using an analysis of variance (ANOVA) or chi-squared tests. Analyses will be performed on an intention-to-treat basis. Potential interaction effects will be calculated using a repeated-measures ANOVA to test the primary and secondary hypotheses. In supplementary analyses, the proportion of treatment responders (those with a 50% reduction in the frequency of pain episodes) will be determined for each treatment arm.

DISCUSSION

This trial may provide evidence for the additive effects of acupuncture and medical training therapy as a combination treatment and may scientifically support the implementation of this complex health intervention.

TRIAL REGISTRATION

Registered on 11 Feburary 2019. German Clinical Trials Register, DRKS00016723.

Subgroups in chronic low back pain patients - a step toward cluster-based, tailored treatment in inpatient standard care: On the need for precise targeting of treatment for chronic low back pain

Objective: The purpose of this study was to find applicable clusters for the development of different treatment pathways in an inpatient multimodal pain-therapy setting based on the multifaceted nature of CLBP. Methods: Based on data of questionnaires (Hospital Anxiety and Depression Scale (HADS), Marburg Questionnaire on Habitual Health Findings (MFHW), quality of life assessment using the Short-Form 12 (SF 12)), a retrospective two-step cluster analysis involving a sample of chronic low back pain (CLBP) patients (N=320) was calculated. Subsequently, the clusters were precisely described and compared on the basis of further data collected during the patients' standard care: pain characteristics, socio-demographic data and the general state of health, psychological variables, therapy intensity, and Diagnosis Related Groups (DRG) data. Results: We found a three-cluster solution: little psychological interference but marginal physical and mental quality of life (Cluster 1); poor well-being, low physical quality of life, and marginal mental quality of life (Cluster 2); and heavy mental strain and marginal physical quality of life (Cluster 3). Conclusions: Similar to previous studies, our results suggest that patients suffering from CLBP differ with regard to the magnitude of mental burden and the presence of physical impairment. These differences ascertain the need for precise targeting of treatment for CLBP. Inpatient pain centers therefore should offer different multimodal therapy pathways and integrate a meaningful triage, taking into account the multifaceted nature of CLBP based on sophisticated knowledge about forms, differences, and relationships among the biopsychosocial components of CLBP.

Childhood traumatization is associated with differences in TRPA1 promoter methylation in female patients with multisomatoform disorder with pain as the leading bodily symptom

Background

The construct of multisomatoform disorder (MSD) is a common point of reference for patients in different somatic and psychosomatic specialties and therefore useful in studying large well-characterized cohorts of a prototype of a somatoform disorder and in parallel as a functional somatic syndrome (FSS). This disorder is characterized by distressing and functionally disabling somatic symptoms with chronic pain as the most frequent and clinically relevant complaint. Pain is perceived by nociceptive nerve fibers and transferred through the generation of action potentials by different receptor molecules known to determine pain sensitivity in pathophysiological processes. Previous studies have shown that for the transient receptor potential ankyrin 1 (TRPA1), receptor methylation of a particular CpG dinucleotide in the promoter region is inversely associated with both heat pain and pressure pain thresholds. In this study, we hypothesized that TRPA1 promoter methylation regulates pain sensitivity of patients with multisomatoform disorder (MSD). A cohort of 151 patients with MSD and 149 matched healthy volunteers were evaluated using quantitative sensory testing, clinical and psychometric assessment, and methylation analysis using DNA isolated from whole blood.

Results

We found CpG -628 to be correlated with mechanical pain threshold and CpG -411 to be correlated with mechanical pain threshold in female volunteers, i.e., higher methylation levels lead to higher pain thresholds. A novel finding is that methylation levels were significantly different between patients with no and severe levels of childhood trauma. CpG methylation also correlated with psychometric assessment of pain and pain levels rated on a visual analog scale.

Conclusion

Our findings support the hypothesis that epigenetic regulation of TRPA1 plays a role in mechanical pain sensitivities in healthy volunteers. They further provide evidence for the possible influence of childhood traumatic experiences on the epigenetic regulation of TRPA1 in patients with MSD.

Electronic supplementary material

The online version of this article (10.1186/s13148-019-0731-0) contains supplementary material, which is available to authorized users.

[Anonymize or personalize? : Does social desirability influence the response behavior of chronic pain patients?]

BACKGROUND

The subjective state of health with respect to pain and psyche was surveyed utilizing validated pain questionnaires in patients undergoing special pain therapy and represents the basis for targeted treatment measures.

OBJECTIVE

The purpose of this study was to investigate the possible distortion of answers due to social desirability of responses in chronic pain patients.

MATERIAL AND METHODS

During two survey periods assessing patient satisfaction using both anonymized and personalized questionnaires, the effects arising from socially desirable response patterns were analyzed. The sample consisted of chronic pain patients being treated in an inpatient therapy setting.

RESULTS

In both periods of observation no significant impact on the response behavior of chronic pain patients was found in personalized or anonymized questionnaires.

CONCLUSION

The results of the study suggest that the responses of chronic pain patients with respect to their subjective state of health are not influenced by social desirability. Thus, scoring systems such as the German pain questionnaire will not be influenced by social desirability in chronic pain patients and can therefore be used as a part of diagnostics and therapy planning.

The beta-adrenergic receptor agonist, terbutaline, reduces UVB-induced mechanical sensitization in humans

OBJECTIVES

Previously, we found in cultures of primary neurons and in animals that sensitized primary neurons can be desensitized by treatment with e.g. beta-adrenergic receptor agonists. We now tested whether also in human sensitization such as UVB-radiation induced sunburn-like hyperalgesia can be reduced by intradermal injection of the beta-adrenergic receptor agonist terbutaline.

METHODS

In our prospective randomized study, 17 participants received an individual UVB dose to cause a defined local sunburn-like erythema at four locations, two on each forearm. Twenty-four hours later, the sensitized four areas were injected intradermally with terbutaline pH 4.3, terbutaline pH 7.0, saline pH 4.3 or saline pH 7.0, respectively. Pain thresholds were examined before and after induction of UVB-sensitization, and 15, 30 and 60 min after injection of the respective solution. Mechanical pain thresholds of the skin and of deeper tissues were determined by pinprick and pressure algometer measurements, respectively.

RESULTS

UVB-irradiation decreased mechanical pain thresholds for pinprick and pressure algometer measurements demonstrating a successful sunburn-like sensitization. Intradermal injection of terbutaline pH 7.0 into the sensitized skin reduced the sensitization for all measured timepoints as determined by pinprick measurements. Pinprick measurements of sensitization were not reduced by injection of terbutaline pH 4.3, saline solution pH 7.0 or saline solution pH 4.3. Also, sensitization of deeper tissue nociceptors were not altered by any of the injections as measured with the pressure algometer.

CONCLUSIONS

Similar to our cellular observations, also in humans beta-adrenergic agonists such as terbutaline can reduce the sensitization of primary neurons in the skin.

SIGNIFICANCE

We previously showed in model systems that beta-adrenergic stimulation can not only sensitize but also desensitize nociceptors. Our study shows that also in humans beta-adrenergic agonists desensitize if injected into UVB-sensitized skin. This indicates an analgesic activity of adrenergic agonists in addition to their vasoconstrictory function.

Venous thromboembolic complications with and without intermittent intraoperative and postoperative pneumatic compression in patients with glioblastoma multiforme using intraoperative magnetic resonance imaging. A retrospective study

OBJECTIVE

To evaluate the effectiveness of intraoperative and postoperative intermittent pneumatic compression (IPC) as a method used to decrease the incidence of deep venous thrombosis (DVT), in comparison to the standard use of graduated compression stockings, low-molecular weight heparin (LMWH) and physiotherapy during the hospital stay. All patients in this study underwent intracranial surgery for glioblastoma multiforme (GBM) using intraoperative magnetic resonance imaging (MRI) guidance.

PATIENTS AND METHODS

We performed a single center retrospective study of a cohort of 153 patients who underwent surgery for GBM aided by intraoperative MRI from October of 2009 to January of 2015 at the International Neuroscience Institute (INI), Hannover, Germany. Out of all patients, 75 in comparison to 78 were operated with and without the additional use of IPC, respectively. Both groups received graduated compression stockings, LMWH and physiotherapy postoperatively as a basic thromboprophylaxis. Postoperatively the patients were screened for DVT by Doppler ultrasonography of the limbs and pulmonary embolism (PE) by CT-scan of the chest.

RESULTS

DVTs were found in 6 patients with IPC and in 3 patients without IPC. The incidence of developing DVTs was therefore not significantly increased with the application of IPC from 3.9% to 8% (P-value: 0.33). No statistically significant differences were found in the probability of occurrence of pulmonary embolism (PE) with a reduction from 2.6% to 1.3% (P-value: 0.59).

CONCLUSION

Our results demonstrate, that the surgical intervention and the subsequent patient immobilization, as well as the thromboprophylactic techniques used have a relatively low influence on the occurrence of thromboembolic complications than we expected. Our findings might be attributed to the overall low number of these complications in a glioblastoma multiforme patient population expected to be at a high risk for coagulopathy. In other words, in order to produce statistically significant results, we would need to increase the patient cohort. By doing so we may better detect a positive therapeutic effect. Alternatively, because of the multitude of possible complex risk-factors leading to coagulopathy in a glioblastoma patient population it might be the case that IPC has little or no effect and that there is a different underlying mechanism responsible for the observed coagulopathy.

Designing a Tablet-Based Software App for Mapping Bodily Symptoms: Usability Evaluation and Reproducibility Analysis

Background

Symptom drawings are widely used as a qualitative and quantitative method of assessing pain symptoms for both clinical and research purposes. As electronic drawings offer many advantages over classical pen-and-paper drawings, the last years have seen a shift toward tablet-based acquisition of symptom drawings. However, software that is used in clinical care requires special attention to usability aspects and design to provide easy access for physically impaired or elderly patients.

Objective

The aims of this project were to develop a new tablet-based software app specifically designed to collect patients’ and doctors’ drawings of pain and related bodily symptoms and test it for usability in 2 samples of chronic pain patients (Aim 1) and their treating doctors (Aim 2) as well as for test-retest reliability (Aim 3).

Methods

In 2 separate studies, symptom drawings from 103 chronic pain patients and their treating doctors were collected using 2 different versions of the app. Both patients and doctors evaluated usability aspects of the app through questionnaires. Results from study 1 were used to improve certain features of the app, which were then evaluated in study 2. Furthermore, a subgroup of 25 patients in study 2 created 2 consecutive symptom drawings for test-retest reproducibility analysis. Usability of both app versions was compared, and reproducibility was calculated for symptom extent, number of symptom clusters, and the whole symptom pattern.

Results

The changes we made to the app and the body outline led to significant improvements in patients’ usability evaluation regarding the identification with the body outline (P=.007) and the evaluation of symptom depth (P=.02), and the overall difficultness of the drawing process (P=.003) improved significantly. Doctors’ usability evaluation of the final app showed good usability with 75.63 (SD 19.51) points on the System Usability Scale, Attrakdiff 2 scores from 0.93 to 1.41, and ISONORM 9241/10 scores from −0.05 to 1.80. Test-retest analysis showed excellent reproducibility for pain extent (intraclass correlation coefficient, ICC=0.92) and good results for the number of symptom clusters (ICC=0.70) and a mean overlap of 0.47 (Jaccard index).

Conclusions

We developed a tablet-based symptom drawing app and improved it based on usability assessment in a sample of chronic pain patients and their treating doctors. Increases in usability of the improved app comprised identification with the body outline, symptom depth evaluation, and difficultness of the drawing process. Test-retest reliability of symptom drawings by chronic pain patients showed fair to excellent reproducibility. Patients’ usability evaluation is an important factor that should not be neglected when designing apps for mobile or eHealth apps.

Sensory Alterations in Patients with Isolated Idiopathic Dystonia: An Exploratory Quantitative Sensory Testing Analysis

Abnormalities in the somatosensory system are increasingly being recognized in patients with dystonia. The aim of this study was to investigate whether sensory abnormalities are confined to the dystonic body segments or whether there is a wider involvement in patients with idiopathic dystonia. For this purpose, we recruited 20 patients, 8 had generalized, 5 had segmental dystonia with upper extremity involvement, and 7 had cervical dystonia. In total, there were 13 patients with upper extremity involvement. We used Quantitative Sensory Testing (QST) at the back of the hand in all patients and at the shoulder in patients with cervical dystonia. The main finding on the hand QST was impaired cold detection threshold (CDT), dynamic mechanical allodynia (DMA), and thermal sensory limen (TSL). The alterations were present on both hands, but more pronounced on the side more affected with dystonia. Patients with cervical dystonia showed a reduced CDT and hot detection threshold (HDT), enhanced TSL and DMA at the back of the hand, whereas the shoulder QST only revealed increased cold pain threshold and DMA. In summary, QST clearly shows distinct sensory abnormalities in patients with idiopathic dystonia, which may also manifest in body regions without evident dystonia. Further studies with larger groups of dystonia patients are needed to prove the consistency of these findings.

Effectiveness of various formulations of local anesthetics and additives for topical anesthesia - a prospective, randomized, double-blind, placebo-controlled study

BACKGROUND

Topical anesthesia is used to control pain associated with many procedures in medicine. Today, the product most commonly applied for topical anesthesia in Germany is EMLA^® (lidocaine/prilocaine). However, since prilocaine is a methemoglobin-inducing agent, there are limitations to its use, especially in neonates and infants. The aim of this study was to evaluate the effect of prilocaine and lidocaine as well as propylene glycol, a penetration enhancer, and trometamol, a buffer substance, in anesthetic creams.

PATIENTS AND METHODS

Twenty-nine healthy adults participated in this study. Standardized creams with eight different compositions were applied and left for 20, 40 or 60 min. After exposure to standardized painful stimuli (blunt/sharp with pressures of 0.2, 0.4 or 0.8 N), subjects rated the experimental pain using a visual analog scale.

RESULTS

Significant results were only found with an exposure time of 60 min and a stamp pressure of 0.8 N. At a concentration of 20%, lidocaine was more effective compared to placebo and equally effective compared to lidocaine/prilocaine in controlling pain. The analgesic effect of the cream containing lidocaine 10% and additional trometamol was significantly superior to that of placebo and non-inferior to that of lidocaine/prilocaine. In this study, the penetration enhancer propylene glycol did not accelerate the onset of the analgesic effect. In contrast, the addition of trometamol (Tris/THAM) accelerated the onset of the effect compared to the native formulation (at 0.4 and 0.8 N). In all of the adult subjects of this study, the minimum exposure time was 60 min for any of the tested topical anesthetic creams.

CONCLUSION

The results of this study indicate that a cream containing 20% lidocaine, 38% trometamol and 10% propylene glycol may be used as an alternative to lidocaine/prilocaine with a comparable effect and without the need to extend exposure time.

The improved quality of postoperative analgesia after intrathecal morphine does not result in improved recovery and quality of life in the first 6 months after orthopedic surgery: a randomized controlled pilot study

Objective

In orthopedic surgery, it is well known that the use of intrathecal morphine (ITM) leads to an improved quality of postoperative analgesia. Little is known how this improved analgesia affects the long-term course after surgery.

Study design

A randomized, double-blind trial.

Setting

Academic medical center.

Subjects

Forty-nine patients undergoing total hip or knee replacement surgery in spinal anesthesia.

Methods

Patients were randomly assigned to receive either 0.1 mg (n=16) or 0.2 mg (n=16) morphine sulfate intrathecally or physiological saline (n=17) added to 3 mL 0.5% isobaric bupivacaine for spinal anesthesia. As a function of the quality of the short-term postoperative analgesia, the effect on recovery and quality of life was evaluated at various time points up to 26 weeks after surgery.

Results

In both ITM groups, the additionally required postoperative systemic morphine dose was significantly reduced compared with the placebo group (P=0.004). One week after operation, patients with ITM reported significantly less pain at rest (P=0.01) compared to the placebo group. At discharge, in comparison with the 0.1 mg ITM and placebo group, the 0.2 mg ITM group showed a higher degree of impairment regarding pain, stiffness, and physical function of the respective joint (P=0.02). Over the further follow-up period of 6 months after surgery, recovery and the quality of life did not differ significantly between the three study groups (P>0.2).

Conclusion

Morphine (0.1 mg) as adjunct to 0.5% bupivacaine for spinal anesthesia is effective to produce a pronounced postoperative analgesia with a beneficial analgesic effect up to 1 week after surgery. With this study design, the different quality of postoperative analgesia had no effect on quality of life and recovery in patients over the 6-month follow-up period. In the medium term, ITM may induce hyperalgesic effects.

Effects of acupuncture on quality of life and pain in patients with osteoporosis-a pilot randomized controlled trial

In this sham-controlled study, 53 patients received 10 sessions of acupuncture treatment over 5 weeks to investigate the effects of acupuncture on the pain and quality of life of patients with osteoporosis. The results showed significant favorable effects of verum acupuncture on quality of life. Both interventions showed sustained and clinically relevant effects on pain.

PURPOSE

Standard analgesic treatment is associated with adverse events in patients with osteoporosis, especially elderly and/or comorbid patients. As acupuncture has gained widespread acceptance as a complementary treatment modality with few side effects, the aim of this study was to evaluate the effects of acupuncture on the pain and quality of life of patients with osteoporosis.

METHODS

In total, 53 patients with vertebral compression fractures, osteoporosis-associated spinal deformities, and resultant pain were randomly allocated to the verum acupuncture with deep needling of specific points following the principles of traditional Chinese medicine (n = 29) or control acupuncture group with superficial needling of non-acupuncture points (n = 24). All patients received 10 sessions of standardized verum or control acupuncture treatment over 5 weeks. Pain (VAS score 1-100) and quality of life (QUALEFFO-41) were measured at the start of treatment (T0), before each acupuncture session (T1), and at 1 (T2) and 3 months (T3) post-treatment.

RESULTS

Both acupuncture treatments significantly reduced activity-related pain and pain at rest over time. The verum acupuncture group experienced a significantly greater reduction in mean pain intensity at rest than the control group. In the control group, quality of life improved only temporarily post-treatment (T2) and slightly declined at the end of the follow-up period (T3). In contrast, patients in the verum acupuncture group experienced continuous and significant improvements in quality of life up to 3 months after treatment (T3).

CONCLUSIONS

Both types of acupuncture were equally effective in producing sustained, clinically relevant pain relief in patients with osteoporosis. Verum acupuncture had stronger and longer-lasting effects on quality of life and pain at rest. The possible reasons for these findings include the specificity of acupuncture point selection and the performance of needle stimulation.

Long-term treatment of chronic migraine with OnabotulinumtoxinA: efficacy, quality of life and tolerability in a real-life setting

Botulinum toxin was shown to be effective in treatment of chronic migraine. We wanted to explore its efficacy and tolerability in chronic application under real-life conditions. For this, 27 consecutive patients (age 45.6 ± 10.8 years, 25 females, 2 males) received altogether 176 injection series (IS) with 189.7 ± 45.8MU onabotulinumtoxinA (Botox(®)) according to the PREEMPT scheme. During the study period altogether 6.5 ± 2.9 (min 4, max 13) IS were applied per patient (total treatment time of 73.1 ± 36.9 weeks). 96 % of the patients reported benefit. Monthly headache days were reduced from 18.9 ± 3.9 to 8.7 ± 4.5 (p < 0.001, -53.7 %), migraine days from 16.8 ± 4.9 to 7.4 ± 4.6 (p < 0.001, -55.1 %), autonomic days from 8.6 ± 7.5 to 2.7 ± 4.2 (p < 0.001, -71.9 %) and medication days from 14.2 ± 4.6 to 8.3 ± 4.2 (p < 0.001, -71.1 %). Health-related quality of life improved by 0.6-1.5 standard deviations (SD) (Short Form Health Survey), migraine-related quality of life by 1.4-2.0 SD (Migraine-Specific Quality of Life Questionnaire) and by 1.9 SD (Headache Impact Test), depression by 1.1 SD (Beck Depression Inventory). Subjective global clinical improvement was 2.6 ± 0.6 (Global Clinical Improvement Scale). All improvements were stable throughout the entire study period. Adverse effects were infrequent, mild and transient. Botulinum toxin provides highly effective and safe long-term treatment of chronic migraine.

Inhibition of voltage-gated Na⁺ channels by the synthetic cannabinoid ajulemic acid

BACKGROUND

The synthetic cannabinoid ajulemic acid has been demonstrated to alleviate pain in patients suffering from chronic neuropathic pain. Cannabinoids interact with several molecules within the pain circuit, including a potent inhibition of voltage-gated sodium channels. In this study, we closely characterized this property on neuronal and nonneuronal sodium channels.

METHODS

The inhibition of sodium inward currents by ajulemic acid was studied in vitro. Human embryonic kidney 293t cells were used as the expression system for Nav1.2, 1.3, 1.4, 1.5, 1.5N406K, 1.5F1760A, and 1.7; Nav1.8 was transiently expressed in ND7/23 cells. Nav1.2, Nav1.3, and Nav 1.8 were from rats, and Nav1.4, Nav1.5, and Nav1.7 were of human origin. Sodium currents were analyzed by means of the whole cell patch-clamp technique. The investigated concentrations of ajulemic acid were 0.1, 0.3, 1, 3, 10, and 30 μmol/L.

RESULTS

Ajulemic acid reversibly and concentration-dependently inhibited all voltage-gated sodium channel (Nav) isoforms investigated in this study, including Nav1.2, 1.3, 1.4, 1.5, 1.7, and 1.8. Tonic block of resting channels yielded half-maximal inhibitory concentration values between 2 and 9 μmol/L and was strongly enhanced on inactivated channels, suggesting state-dependent inhibition by ajulemic acid. Tonic block did not differ significantly when comparing Nav1.2 and Nav1.3, Nav1.4 and Nav1.5, and Nav1.7 and Nav1.8. Statistical analysis of other combinations of subunits (e.g., Nav1.2 and Nav1.4) by analysis of variance yielded a significant difference in block. Although we did not observe any relevant use-dependent block, ajulemic acid induced a strong hyperpolarizing shift of the voltage dependency of fast inactivation and modest shift of slow inactivation. The local anesthetic-insensitive Nav1.5 constructs N406K and F1760A displayed a preserved sensitivity to block by ajulemic acid. Finally, we found that low concentrations of ajulemic acid efficiently inhibited Navβ4 peptide-mediated resurgent currents in Nav1.5.

CONCLUSIONS

Our data suggest that block of sodium channels can be a relevant mechanism by which ajulemic acid alleviates neuropathic pain. The potent inhibition of resurgent currents and the preserved block on local anesthetic-insensitive channels indicates that ajulemic acid interacts with a conserved but yet unknown site of sodium channels.

Alteration in forward model prediction of sensory outcome of motor action in focal hand dystonia

Focal hand dystonia in musicians is a movement disorder affecting highly trained movements. Rather than being a pure motor disorder related to movement execution only, movement planning, error prediction, and sensorimotor integration are also impaired. Internal models (IMs), of which two types, forward and inverse models have been described and most likely processed in the cerebellum, are known to be involved in these tasks. Recent results indicate that the cerebellum may be involved in the pathophysiology of focal dystonia (FD). Thus, the aim of our study was to investigate whether an IM deficit plays a role in FD. We focused on the forward model (FM), which predicts sensory consequences of motor commands and allows the discrimination between external sensory input and input deriving from motor action. We investigated 19 patients, aged 19-59 and 19 healthy musicians aged 19-36 as controls. Tactile stimuli were applied to fingers II-V of both hands by the experimenter or the patient. After each stimulus the participant rated the stimulus intensity on a scale between 0 (no sensation) and 1 (maximal intensity). The difference of perceived intensity between self- and externally applied (EA) stimuli was then calculated for each finger. For assessing differences between patients and controls we performed a cluster analysis of the affected hand and the corresponding hand of the controls using the fingers II-V as variables in a 4-dimensional hyperspace (chance level = 0.5). Using a cluster analysis, we found a correct classification of the affected finger in 78.9-94.7%. There was no difference between patients and healthy controls of the absolute value of the perceived stimulus intensity. Our results suggest an altered FM function in focal hand dystonia. It has the potential of suggesting a neural correlate within the cerebellum and of helping integrate findings with regard to altered sensorimotor processing and altered prediction in FD in a single framework.

Changes of blood endocannabinoids during anaesthesia: a special case for fatty acid amide hydrolase inhibition by propofol?

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Available data from animal studies suggest that the narcotic drug propofol interacts with the endocannabinoid system. Inhibition of enzymatic degradation of anandamide could explain some of the characteristics of propofol. Direct measurements have not been reported yet in humans.

WHAT THIS STUDY ADDS

• Propofol does not change the time course of anandamide plasma concentrations during anaesthesia. Furthermore, propofol does not inhibit fatty acid amide hydrolase activity ex vivo or in vitro. Thus, specific characteristics of the narcotic drug propofol cannot be explained by peripheral inhibition of anandamide degradation in humans.

AIMS

The aim of our study was to describe the time course of endocannabinoids during different anaesthesia protocols in more detail, and to challenge the hypothesis that propofol acts as a FAAH inhibitor.

METHODS

Endocannabinoids were measured during the first hour of anaesthesia in 14 women and 14 men undergoing general anaesthesia with propofol and in 14 women and 14 men receiving thiopental/sevoflurane. We also incubated whole human blood samples ex vivo with propofol and the known FAAH inhibitor oloxa and determined FAAH enzyme kinetics.

RESULTS

Plasma anandamide decreased similarly with propofol and thiopental/sevoflurane anaesthesia, and reached a nadir after 10 min. Areas under the curve for anandamide (mean and 95% CI) were 53.3 (47.4, 59.2) nmol l(-1) 60 min with propofol and 48.5 (43.1, 53.8) nmol l(-1) 60 min with thiopental/sevoflurane (P= NS). Anandamide and propofol plasma concentrations were not correlated at any time point. Ex vivo FAAH activity was not inhibited by propofol. Enzyme kinetics (mean ± SD) of recombinant human FAAH were K(m) = 16.9 ± 8.8 µmol l(-1) and V(max) = 44.6 ± 15.8 nmol mg(-1) min(-1) FAAH without, and K(m) = 16.6 ± 4.0 µmol l(-1) and V(max) = 44.0 ± 7.6 nmol mg( 1 ) min(-1) FAAH with 50 µmol l(-1) propofol (P= NS for both).

CONCLUSIONS

Our findings challenge the idea that propofol anaesthesia and also propofol addiction are directly mediated by FAAH inhibition, but we cannot exclude other indirect actions on cannabinoid receptors.

Ca++/CaMKII switches nociceptor-sensitizing stimuli into desensitizing stimuli

Many extracellular factors sensitize nociceptors. Often they act simultaneously and/or sequentially on nociceptive neurons. We investigated if stimulation of the protein kinase C epsilon (PKCε) signaling pathway influences the signaling of a subsequent sensitizing stimulus. Central in activation of PKCs is their transient translocation to cellular membranes. We found in cultured nociceptive neurons that only a first stimulation of the PKCε signaling pathway resulted in PKCε translocation. We identified a novel inhibitory cascade to branch off upstream of PKCε, but downstream of Epac via IP3-induced calcium release. This signaling branch actively inhibited subsequent translocation and even attenuated ongoing translocation. A second 'sensitizing' stimulus was rerouted from the sensitizing to the inhibitory branch of the signaling cascade. Central for the rerouting was cytoplasmic calcium increase and CaMKII activation. Accordingly, in behavioral experiments, activation of calcium stores switched sensitizing substances into desensitizing substances in a CaMKII-dependent manner. This mechanism was also observed by in vivo C-fiber electrophysiology corroborating the peripheral location of the switch. Thus, we conclude that the net effect of signaling in nociceptors is defined by the context of the individual cell's signaling history.

Interaction of the dopaminergic and serotonergic systems significantly influences the risk for multisomatoform disorder: a controlled pilot study

The etiology of multisomatoform disorder (MSD) is largely unknown, but an influence of genetic factors is likely. Since pain is a major component of MSD and dopamine as well as serotonin are involved in pain pathways, genes of the dopaminergic and serotonergic system are promising candidate genes and we assumed that polymorphisms could be associated with MSD. One hundred forty-nine patients with MSD and 149 age- and gender-matched healthy controls participated in this study. DNA from all participants was genotyped for 22 single nucleotide polymorphisms (SNPs) within genes of the dopaminergic and serotonergic system by polymerase chain reaction, a restriction enzyme analysis, and pyrosequencing. The distribution of SNP alleles, genotypes, and haplotypes was compared between patients and controls. Neither an allelic nor a genotypic association was found for any individual SNP, but testing for a haplotypic association revealed that a haplotype of the serotonergic genes HT(1B) and HT(1D) indicated a lower risk. However, this statistically insignificant protective effect became highly significant on the background of two DAT1 haplotypes. Interestingly, if these two DAT1 haplotypes are analyzed without considering the serotonergic genes as confounders, they are significantly associated with an enhanced risk. Taking into account observations from recent publications, this apparent contradiction might be explained with the complex interaction of the dopaminergic and serotonergic systems. To conclude, our results reveal an involvement of polymorphisms in dopaminergic and serotonergic genes in the etiology of MSD in patients of German descent, but their exact role in MSD requires further investigation.

Mitigation of post-traumatic stress symptoms by Cannabis resin: a review of the clinical and neurobiological evidence

It is known from clinical studies that some patients attempt to cope with the symptoms of post-traumatic stress disorder (PTSD) by using recreational drugs. This review presents a case report of a 19-year-old male patient with a spectrum of severe PTSD symptoms, such as intense flashbacks, panic attacks, and self-mutilation, who discovered that some of his major symptoms were dramatically reduced by smoking cannabis resin. The major part of this review is concerned with the clinical and preclinical neurobiological evidence in order to offer a potential explanation of these effects on symptom reduction in PTSD. This review shows that recent studies provided supporting evidence that PTSD patients may be able to cope with their symptoms by using cannabis products. Cannabis may dampen the strength or emotional impact of traumatic memories through synergistic mechanisms that might make it easier for people with PTSD to rest or sleep and to feel less anxious and less involved with flashback memories. The presence of endocannabinoid signalling systems within stress-sensitive nuclei of the hypothalamus, as well as upstream limbic structures (amygdala), point to the significance of this system for the regulation of neuroendocrine and behavioural responses to stress. Evidence is increasingly accumulating that cannabinoids might play a role in fear extinction and antidepressive effects. It is concluded that further studies are warranted in order to evaluate the therapeutic potential of cannabinoids in PTSD.