InterMiG: international differences in the therapeutic approach to migraine patients in specialized headache centers.

BACKGROUND: There is currently a wide therapeutic arsenal for migraine patients, without a single first-line preventive drug and we choose the different available alternatives taking into account comorbidities, national guidelines, previous treatments and personal experiences. Our objective was to evaluate the differences in the use of migraine treatments between neurologists from different countries. METHODS: This is a multi-centre observational study carried out by neurologists from specialized headache units in seven countries, retrospective with consecutive inclusion of all patients presenting with a migraine diagnosis, over a period of three months. RESULTS: A total of 734 patients were recruited but only 600 were considered in the analysis in order to homogenize the patient cohorts from countries: 200 Spain (ES), 100 Italy (IT), 85 Russia (RUS), 80 Germany (DE), 60 Portugal (PT), 45 Poland (PL) and 30 Australia (AU). 85.4 % of patients were women with a mean age of 42.6 ± 11.8 years. Considering previous and current preventive treatment, the order of use was: antidepressants (69.3 %), antiepileptic drugs (54.7 %), beta-blockers and antihypertensive drugs (49.7 %), OnabotulinumtoxinA (44.0 %) and others (36.2 %). Statistically significant differences were found between all pharmacological classes: antidepressants were commonly used in all countries, with the exception of Poland (AU: 76.7 %, IT: 71.0 %, DE: 60.0 %, PL: 31.1 %, PT: 71.7 %, RUS: 70.6 %, ES: 78.5 %; p < 0.0001); antiepileptic drugs were more frequently prescribed in Portugal, Australia and Spain (AU: 73.3 %, IT: 40.0 %, DE: 37.5 %, PL: 48.9 %, PT: 85.0 %, RUS: 29.4 % and ES: 69.0 %; p < 0.0001); beta-blockers and antihypertensive drugs were frequently used in all countries except Italy (AU: 60.0 %, IT: 14.0 %, DE: 53.8 %, PL: 48.9 %, PT: 68.3 %, RUS: 49.4 % and ES: 59.0 %; p < 0.0001); BTX-A were predominately used in Spain, Italy and Australia (AU:56.7 %, IT:58.0 %, DE:20.0 %, PL: 42.2 %, PT: 26.7 %, RUS: 24.7 % and ES: 58.5 %; p < 0.0001) and others were most frequently used in Poland (AU: 0.0 %, IT: 19.0 %, DE: 42.5 %, PL: 95.6 %, PT: 31.7 %, RUS: 3.5 % and ES: 49.5 %; p < 0.0001). If only patients without comorbidities are considered (200/600), statistically differences between countries persist in all preventive treatments. CONCLUSIONS: There is heterogeneity in the choice of preventive treatment between different countries. Prospective comparative studies of the different oral and subcutaneous alternatives would help to create a global therapeutic algorithm that would guarantee the best option for our patients.

[Digitalization in headache therapy]. / Digitalisierung in der Kopfschmerzbehandlung.

BACKGROUND: Digitalization offers support and innovative approaches in the diagnosis and therapy of headaches. With the German digital health care act (Digitale-Versorgung-Gesetz) it is now possible to integrate this into regular care for the first time. However, it is currently difficult to assess the various offers; quality standards and conclusive studies to determine the efficacy and safety are missing. AIM: Overview of current digital approaches in headache treatment and presentation of two specific examples (App M­sense and DMKG headache registry). MATERIALS AND METHODS: Literature research, product information, and presentations by the project managers. RESULTS: Most digital offers for headache treatment are currently headache calendars, mostly as a smartphone app. However, there are also promising extensions (e.g. trigger analysis) and new approaches such as digital instructions for relaxation and endurance sports, chatbots for patients, as well as support for doctors through structured collection of patient data and processing for diagnostic purposes. CONCLUSION: Different digital approaches could support practitioners and patients effectively in headache treatment and therapy guidance in the near future. However, high-quality studies are necessary to evaluate their benefits and efficacy.

[Treatment of chronic migraine with botulinum neurotoxin A : Expert recommendations of the German Migraine and Headache Society]. / Therapie der chronischen Migräne mit Botulinumneurotoxin A : Expertenempfehlung der Deutschen Migräne- und Kopfschmerzgesellschaft.

BACKGROUND: Injection of botulinum neurotoxin A (BoNT-A) according to the PREEMPT (Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy) paradigm has been approved for the treatment of refractory chronic migraine in Germany in 2011. OBJECTIVE: The practical application raises some questions, such as the choice of dose and injection intervals during the course of the treatment, and the appropriate time point for discontinuation of BoNT-A treatment. MATERIAL AND METHODS: Taking into account the existing literature, the German Migraine and Headache Society (Deutsche Migräne- und Kopfschmerzgesellschaft, DMKG) gives recommendations for the treatment of chronic migraine with BoNT-A. RESULTS: Treatment is usually started with a dose of 155 U BoNT-A. During the first year of treatment, 3­month injection intervals are recommended. Goal of the treatment is an improvement of migraine by ≥30%. If needed, dose escalation up to 195 U can be used to reach this goal. If improvement by ≥30% is not reached after the third injection cycle, the treatment is usually considered to be insufficiently efficient and discontinuation is recommended. If a stable success is reached during the first year of treatment, prolongation of injection intervals to 4 months can be considered. If success continues to be stable for at least two 4­month intervals, discontinuation of BoNT-A treatment can be tried. CONCLUSION: The literature on these points is insufficient for recommendations at the guideline level. The present recommendations are based on an expert consensus of the DMKG for the structured approach to the treatment of chronic migraine with BoNT-A.

Effects of stress and relaxation on pain perception in subjects with pain-free occlusional disharmony compared with healthy controls.

OBJECTIVES: The significance of occlusal disharmony for the development of painful temporomandibular disorder (TMD) is controversial. The ongoing biomechanical strain caused by occlusal disharmony might lead to sensitization processes in the nociceptive system. Understanding these processes might be an important step toward understanding the possible relationship between occlusal disharmony and TMD. In this study, we therefore investigated whether subjects with occlusal disharmony (n = 22) differ from healthy controls (n = 26) in their pain perception and pain modulation by stress and relaxation. MATERIALS AND METHODS: Trigeminal and extratrigeminal experimental pain perception (pinprick, heat, and pressure pain) was assessed before and after stress (mental arithmetic) and relaxation (viewing of low-arousal pictures). RESULTS: There were no group differences in pain perception at baseline or during the stress task. Compared with controls, the occlusal disharmony group exhibited an inadequate reduction in pain perception during relaxation, which was significant for the extratrigeminal site (P < 0.01) and reached a trend for significance at the trigeminal site (P = 0.1). CONCLUSIONS: These results suggest that subjects with occlusal disharmony show signs of disturbed endogenous pain inhibition during relaxation. CLINICAL RELEVANCE: There is evidence for the presence of sensitization of the nociceptive system in subjects with occlusal disharmony. Possibly, deficient inhibition of extratrigeminal and trigeminal pain perception by relaxation might contribute to the development of TMD or other chronic pain disorders.

Treatment of chronic migraine with transcutaneous stimulation of the auricular branch of the vagal nerve (auricular t-VNS): a randomized, monocentric clinical trial.

BACKGROUND: Aim of the study was assessment of efficacy and safety of transcutaneous stimulation of the auricular branch of the vagal nerve (t-VNS) in the treatment of chronic migraine. METHODS: A monocentric, randomized, controlled, double-blind study was conducted. After one month of baseline, chronic migraine patients were randomized to receive 25 Hz or 1 Hz stimulation of the sensory vagal area at the left ear by a handhold battery driven stimulator for 4 h/day during 3 months. Headache days per 28 days were compared between baseline and the last month of treatment and the number of days with acute medication was recorded The Headache Impact Test (HIT-6) and the Migraine Disability Assessment (MIDAS) questionnaires were used to assess headache-related disability. RESULTS: Of 46 randomized patients, 40 finished the study (per protocol). In the per protocol analysis, patients in the 1 Hz group had a significantly larger reduction in headache days per 28 days than patients in the 25 Hz group (-7.0 ± 4.6 vs. -3.3 ± 5.4 days, p = 0.035). 29.4 % of the patients in the 1 Hz group had a ≥50 % reduction in headache days vs. 13.3 % in the 25 Hz group. HIT-6 and MIDAS scores were significantly improved in both groups, without group differences. There were no serious treatment-related adverse events. CONCLUSION: Treatment of chronic migraine by t-VNS at 1 Hz was safe and effective. The mean reduction of headache days after 12 weeks of treatment exceeded that reported for other nerve stimulating procedures.

OnabotulinumtoxinA in elderly patients with chronic migraine: insights from a real-life European multicenter study.

INTRODUCTION: Although migraine prevalence decreases with aging, some older patients still suffer from chronic migraine (CM). This study aimed to investigate the outcome of OnabotulinumtoxinA (OBT-A) as preventative therapy in elderly CM patients. METHODS: This is a post hoc analysis of real-life prospectively collected data at 16 European headache centers on CM patients treated with OBT-A over the first three treatment cycles (i.e., Cy1-3). We defined: OLD patients aged ≥ 65 years and nonOLD those < 65-year-old. The primary endpoint was the changes in monthly headache days (MHDs) from baseline to Cy 1-3 in OLD compared with nonOLD participants. The secondary endpoints were the responder rate (RR) ≥ 50%, conversion to episodic migraine (EM) and the changes in days with acute medication use (DAMs). RESULTS: In a cohort of 2831 CM patients, 235 were OLD (8.3%, 73.2% females, 69.6 years SD 4.7). MHDs decreased from baseline (24.8 SD 6.2) to Cy-1 (17.5 SD 9.1, p < 0.000001), from Cy-1 to Cy-2 (14.8 SD 9.2, p < 0.0001), and from Cy-2 to Cy-3 (11.9 SD 7.9, p = 0.001). DAMs progressively reduced from baseline (19.2 SD 9.8) to Cy-1 (11.9 SD 8.8, p < 0.00001), to Cy-2 (10.9 SD 8.6, p = 0.012), to Cy-3 (9.6 SD 7.4, p = 0.049). The 50%RR increased from 30.7% (Cy-1) to 34.5% (Cy-2), to 38.7% (Cy-3). The above outcome measures did not differ in OLD compared with nonOLD patients. CONCLUSION: In a population of elderly CM patients with a long history of migraine OBT-A provided a significant benefit, over the first three treatment cycles, as good as in non-old patients.

No game, more pain - Examining possible long term effects and underlying mechanisms of habitual violent video gaming on the acquired capability for suicide.

According to Joiner`s interpersonal-psychological theory of suicide repeated engagement in suicidal behavior or so-called painful and provocative events constitutes the acquired capability for suicide (ACS) comprising two facets: enhanced pain tolerance and fearlessness about death (FAD). Recent research showed that single bouts of violent-video-gaming (VVG) increase pain tolerance. It is unknown whether individuals who habitually play VVGs at a high frequency rate show higher signs of ACS in terms of low pain sensitivity, high tolerance and lowered FAD compared to non-gamers. In a cross-sectional case-control study, we compared pain sensitivity and tolerance during a 5-min Cold-Pressor-Test (CPT) besides FAD in young males, playing VVGs highly frequent (n = 18) vs. non-gamers (n = 17). Mood was rated before and after the CPT. We found higher CPT-pain tolerance, lower intensity ratings and higher FAD scores among gamers compared to non-gamers. A significant time x group interaction of pain ratings indicated a process of habituation in the gamers. An increase of positive mood in the gamers emphasizes the role of opponent processes. The results suggest that habitual VVG might reflect a repetitive behavior enhancing the ACS.

Physical activity and memory functions: are neurotrophins and cerebral gray matter volume the missing link?

Epidemiological studies reveal better cognitive function in physically active individuals. Possible mediators for this effect are neurotrophins, which are up-regulated through physical exercise and induce neuronal growth and synaptogenesis in the animal model. Here we cross-sectionally assessed 75 healthy older individuals for levels of physical activity, aerobic fitness, and memory encoding, as well as neurotrophin levels and cerebral gray matter volume. We found that physical activity, but not cardiovascular fitness, was associated with better memory encoding after controlling for age, sex, education, depression, alcohol consumption, and smoking. Higher levels of physical activity were associated with higher levels of the neurotrophin granulocyte colony stimulating factor (G-CSF) and increased cerebral gray matter volume in prefrontal and cingulate cortex as assessed by magnetic resonance voxel-based morphometry. While mediating factors will need to be further elucidated, these findings indicate that even low-level physical activity exerts beneficial effects on memory functions in older individuals.

Learned control over spinal nociception in patients with chronic back pain.

BACKGROUND: Descending pain inhibition suppresses spinal nociception, reducing nociceptive input to the brain. It is modulated by cognitive and emotional processes. In subjects with chronic pain, it is impaired, possibly contributing to pain persistence. A previously developed feedback method trains subjects to activate their descending inhibition. Participants are trained to use cognitive-emotional strategies to reduce their spinal nociception, as quantified by the nociceptive flexor reflex (RIII reflex), under visual feedback about their RIII reflex size. The aim of the present study was to test whether also subjects with chronic back pain can achieve a modulation of their descending pain inhibition under RIII feedback. METHODS: In total, 33 subjects with chronic back pain received either true (n = 18) or sham RIII feedback (n = 15), 15 healthy control subjects received true RIII feedback. RESULTS: All three groups achieved significant RIII suppression, largest in controls (to 76 ± 26% of baseline), intermediate in chronic back pain subjects receiving true feedback (to 82 ± 13%) and smallest in chronic back pain subjects receiving sham feedback (to 89 ± 14%, all p < 0.05). However, only chronic pain subjects receiving true feedback significantly improved their descending inhibition over the feedback training, quantified by the conditioned pain modulation effect (test pain reduction of baseline before training: to 98 ± 26%, after: to 80 ± 21%, p < 0.01). CONCLUSION: Our results show that subjects with chronic back pain can achieve a reduction of their spinal nociception and improve their descending pain inhibition under RIII feedback training. SIGNIFICANCE: Subjects with chronic back pain can learn to control their spinal nociception, quantified by the RIII reflex, when they receive feedback about the RIII reflex.

Possible sources and sites of action of the nitric oxide involved in synaptic plasticity at spinal lamina I projection neurons.

The synaptic long-term potentiation between primary afferent C-fibers and spinal lamina I projection neurons is a cellular model for hyperalgesia [Ikeda H, Heinke B, Ruscheweyh R, Sandkühler J (2003) Synaptic plasticity in spinal lamina I projection neurons that mediate hyperalgesia. Science 299:1237-1240]. In lamina I neurons with a projection to the periaqueductal gray, this long-term potentiation is dependent on nitric oxide. In the present study, we used immunohistochemistry to detect possible sources and sites of action of the nitric oxide necessary for the long-term potentiation at lamina I spino-periaqueductal gray neurons in rats. None of the three isoforms of the nitric oxide synthase was expressed in a significant number of lamina I spino-periaqueductal gray neurons or primary afferent C-fibers (as evaluated by staining of their cell bodies in the dorsal root ganglia). However, endothelial and inducible nitric oxide synthase were found throughout the spinal cord vasculature and neuronal nitric oxide synthase was present in a number of neurons in laminae II and III. The nitric oxide target soluble guanylyl cyclase was detected in most lamina I spino-periaqueductal gray neurons and in approximately 12% of the dorsal root ganglion neurons, all of them nociceptive as evaluated by coexpression of substance P. Synthesis of cyclic 3',5'-guanosine monophosphate upon stimulation by a nitric oxide donor confirmed the presence of active guanylyl cyclase in at least a portion of the spino-periaqueductal gray neuronal cell bodies. We therefore propose that nitric oxide generated in neighboring neurons or blood vessels acts on the spino-periaqueductal gray neuron and/or the primary afferent C-fiber to enable long-term potentiation. Lamina I spino-parabrachial neurons were stained for comparison and yielded similar results.

Control over spinal nociception as quantified by the nociceptive flexor reflex (RIII reflex) can be achieved under feedback of the RIII reflex.

BACKGROUND: Descending pain modulatory systems control transmission of nociceptive information at the spinal level, and their activity can be modified by cognitive and emotional processes. Thus, it may be possible to learn using cognitive-emotional strategies to specifically target descending pathways in order to achieve pain reduction. METHODS: The present study used visual feedback of the nociceptive flexor reflex (RIII reflex) to train healthy subjects over three sessions to reduce their spinal nociception (RIII reflex size) by self-selected cognitive-emotional strategies. The study included two feedback groups (fixed vs. random stimulation intervals) and a control group without feedback (15 subjects each). RESULTS: While all three groups successfully reduced their RIII reflexes (p < 0.01), reductions were larger in the feedback groups (p < 0.05). Success increased over training sessions in the feedback groups (p < 0.05). In the third session, RIII was reduced to 90 ± 15% of baseline in the control group, and to 72 ± 24 and 66 ± 22% in the feedback groups. Most subjects used mental imagery or relaxation to achieve RIII reduction. Pain reduction correlated with RIII reduction in the feedback groups, but was not significantly different between feedback and control groups. CONCLUSIONS: The present results suggest that healthy subjects are able to learn using cognitive and emotional strategies to reduce their spinal nociception under feedback of their RIII reflex size. However, future studies will have to include a sham feedback group to differentiate true learning effects from expectancy effects induced by the feedback procedure.

Bidirectional actions of nociceptin/orphanin FQ on A delta-fibre-evoked responses in rat superficial spinal dorsal horn in vitro.

The present study investigated the modulatory actions of nociceptin/orphanin FQ on excitatory glutamatergic transmission in spinal dorsal horn. In transverse spinal cord slices with an attached dorsal root, mono- and polysynaptic A delta-fibre-evoked extracellular field potentials were recorded from superficial dorsal horn. Nociceptin/orphanin FQ showed bidirectional effects on monosynaptic transmission with a potentiation at lower concentrations (100-300 nM) and a dose-dependent depression at higher concentrations (1-3 microM). The polysynaptic field potential was dose-dependently depressed by nociceptin/orphanin FQ (100 nM-3 microM). None of the actions of nociceptin/orphanin FQ was reversed by the non-specific opioid receptor antagonist naloxone, the N-methyl-D-aspartate receptor antagonist D-2-amino-5-phosphonovaleric acid or the peptide nocistatin. The bidirectional actions of nociceptin/orphanin FQ on the monosynaptic field potential may provide an in vitro model for the bidirectional actions of nociceptin/orphanin FQ in behavioural studies showing hyperalgesia at low doses of intrathecal nociceptin/orphanin FQ and analgesia at higher doses.

Reproducibility of contact heat evoked potentials (CHEPs) over a 6 months interval.

OBJECTIVE: Contact heat evoked potentials (CHEPs) mediated by primary afferent Aδ-fibers can be recorded at the vertex. CHEPs are reduced in small fibre neuropathy and considered as a noninvasive measure of small fibre function. As long-term stability of CHEPs has not been examined, it is presently not clear if CHEPs may also be useful for following the course of small fibre neuropathy. METHODS: Here, we analyzed CHEPs from 60 healthy subjects recorded at two occasions separated by 6 months. RESULTS: There was a systematic shift towards larger amplitudes (from 40.2 ± 13.8 µV to 53.3 ± 17.5 µV, p<0.001) and towards shorter latencies (from 425.0 ± 28.8 ms to 387.2 ± 30.3 ms, p<0.001) after six months, while CHEP areas were more constant over time. CONCLUSIONS: The present results show that systematic changes of CHEP amplitudes and latencies may occur over time. Possible reasons include seasonal differences in skin conductivity for heat and psychological effects. SIGNIFICANCE: CHEP areas seem to be more stable over time than amplitudes or latencies, however, it remains to be determined if CHEP areas differentiate between subjects with lesions of the nociceptive system and healthy controls as reliably as CHEP amplitudes.

Physical activity and memory functions: an interventional study.

Previous studies have suggested beneficial effects of physical activity on cognition. Here, we asked in an interventional approach if physical activity performed at different intensity levels would differentially affect episodic memory function. Additionally, we tried to identify mechanisms mediating these changes. Sixty-two healthy elderly individuals were assessed for level of physical activity, aerobic fitness, episodic memory score, neurotrophin and catecholamine levels, and received a magnetic resonance image of the brain at baseline and after a six months intervention of medium or low-intensity physical activity or control. Increase in total physical activity was positively associated with increase in memory score over the entire cohort, without significant differences between intensity groups. It was also positively associated with increases in local gray matter volume in prefrontal and cingulate cortex, and BDNF levels (trend). In conclusion, we showed that physical activity conveys the beneficial effects on memory function independently of its intensity, possibly mediated by local gray matter volume and neurotrophic factors. Our findings may carry significant implications for prevention of cognitive decline in the elderly.