Signature of Alzheimer’s Disease in Intestinal Microbiome: Results From the AlzBiom Study

Background: Changes in intestinal microbiome composition have been described in animal models of Alzheimer’s disease (AD) and AD patients. Here we investigated how well taxonomic and functional intestinal microbiome data and their combination with clinical data can be used to discriminate between amyloid-positive AD patients and cognitively healthy elderly controls. Methods: In the present study we investigated intestinal microbiome in 75 amyloid-positive AD patients and 100 cognitively healthy controls participating in the AlzBiom study. We randomly split the data into a training and a validation set. Intestinal microbiome was measured using shotgun metagenomics. Receiver operating characteristic (ROC) curve analysis was performed to examine the discriminatory ability of intestinal microbiome among diagnostic groups. Results: The best model for discrimination of amyloid-positive AD patients from healthy controls with taxonomic data was obtained analyzing 18 genera features, and yielded an area under the receiver operating characteristic curve (AUROC) of 0.76 in the training set and 0.61 in the validation set. The best models with functional data were obtained analyzing 17 GO (Gene Ontology) features with an AUROC of 0.81 in the training set and 0.75 in the validation set and 26 KO [Kyoto Encyclopedia of Genes and Genomes (KEGG) ortholog] features with an AUROC of 0.83 and 0.77, respectively. Using ensemble learning for these three models including a clinical model with the 4 parameters age, gender, BMI and ApoE yielded an AUROC of 0.92 in the training set and 0.80 in the validation set. Discussion: In conclusion, we identified a specific Alzheimer signature in intestinal microbiome that can be used to discriminate amyloid-positive AD patients from healthy controls. The diagnostic accuracy increases from taxonomic to functional data and is even better when combining taxonomic, functional and clinical models. Intestinal microbiome represents an innovative diagnostic supplement and a promising area for developing novel interventions against AD

Decreased Autonomic Reactivity and Psychiatric Comorbidities in Neurological Patients With Medically Unexplained Sensory Symptoms: A Case-Control Study

Up to 48% of patients with medically unexplained symptoms seen in neurological practice suffer from sensory symptoms, which could be of functional nature or secondary to psychiatric disorders. These patients show high medical care utilization causing elevated healthcare costs. Despite the high prevalence, little is known about clinical characteristics and pathophysiological mechanisms. For functional disorders such as irritable bowel syndrome, a reduction of heart rate variability (HRV) has been shown, suggesting a dysfunction of the autonomic nervous system (ANS). The aim of this study was to investigate psychological data and functional changes of the ANS in patients with medically unexplained sensory symptoms (MUSS). In this exploratory pilot study, 16 patients (11 females, 31.6 ± 11.9 years) with MUSS, who were recruited at a single tertiary neurological center, underwent a structured clinical interview (SCID) to evaluate psychiatric comorbidities. Patients and age- and sex-matched healthy volunteers filled in questionnaires, and individual sensory thresholds (perception, pain) were detected by quantitative sensory testing (QST). HRV was assessed at baseline and under three different experimental conditions (tonic pain stimulus, placebo application, cold-face test). All tests were repeated after 6–8 weeks. SCID interviews revealed clinical or subclinical diagnoses of psychiatric comorbidities for 12 patients. Questionnaires assessing somatization, depression, anxiety, and perceived stress significantly discriminated between patients with MUSS and healthy controls. While there was no difference in QST, reduced ANS reactivity was found in patients during experimental conditions, particularly with regard to vagally mediated HRV. Our pilot study of neurological patients with MUSS reveals a high prevalence of psychiatric comorbidities and provides evidence for altered ANS function. Our data thus give insight in possible underlying mechanisms for these symptoms and may open the door for a better diagnostic and therapeutic approach for these patients in the future

Triptan non-response in specialized headache care: cross-sectional data from the DMKG Headache Registry

Abstract Background Triptans are effective for many migraine patients, but some do not experience adequate efficacy and tolerability. The European Headache Federation (EHF) has proposed that patients with lack of efficacy and/or tolerability of ≥ 2 triptans (‘triptan resistance’) could be considered eligible for treatment with the novel medications from the ditan and gepant groups. There is little data on the frequency of ‘triptan resistance’. Methods We used patient self-report data from the German Migraine and Headache Society (DMKG) Headache Registry to assess triptan response and triptan efficacy and/or tolerability failure. Results A total of 2284 adult migraine patients (females: 85.4%, age: 39.4 ± 12.8 years) were included. 42.5% (n = 970) had failed ≥ 1 triptan, 13.1% (n = 300) had failed ≥ 2 triptans (meeting the EHF definition of ‘triptan resistance’), and 3.9% (n = 88) had failed ≥ 3 triptans. Compared to triptan responders (current use, no failure, n = 597), triptan non-responders had significantly more severe migraine (higher frequency (p < 0.001), intensity (p < 0.05), and disability (p < 0.001)), that further increased with the level of triptan failure. Responders rates were highest for nasal and oral zolmitriptan, oral eletriptan and subcutaneous sumatriptan. Conclusion In the present setting (specialized headache care in Germany), 13.1% of the patients had failed ≥ 2 triptans. Triptan failure was associated with increased migraine severity and disability, emphasizing the importance of establishing an effective and tolerable acute migraine medication. Acute treatment optimization might include switching to one of the triptans with the highest responder rates and/or to a different acute medication class. Trial registration The DMKG Headache Registry is registered with the German Clinical Trials Register (DRKS 00021081)

[Consensus statement of the migraine and headache societies (DMKG, ÖKSG, and SKG) on the duration of pharmacological migraine prophylaxis].

Migraine is the most common neurological disorder and can be associated with a high degree of disability. In addition to non-pharmacological approaches to reduce migraine frequency, pharmacological migraine preventatives are available. Evidence-based guidelines from the German Migraine and Headache Society (DMKG), and German Society for Neurology (DGN), Austrian Headache Society (ÖKSG), and Swiss Headache Society (SKG) are available for indication and application. For therapy-relevant questions such as the duration of a pharmacological migraine prevention, no conclusions can be drawn from currently available study data. The aim of this review is to present a therapy consensus statement that integrates the current data situation and, where data are lacking, expert opinions. The resulting current recommendations on the duration of therapy for pharmacological migraine prophylaxis are shown here