A Precision Medicine Initiative for Alzheimer's disease: the road ahead to biomarker-guided integrative disease modeling.

After intense scientific exploration and more than a decade of failed trials, Alzheimer's disease (AD) remains a fatal global epidemic. A traditional research and drug development paradigm continues to target heterogeneous late-stage clinically phenotyped patients with single 'magic bullet' drugs. Here, we propose that it is time for a paradigm shift towards the implementation of precision medicine (PM) for enhanced risk screening, detection, treatment, and prevention of AD. The overarching structure of how PM for AD can be achieved will be provided through the convergence of breakthrough technological advances, including big data science, systems biology, genomic sequencing, blood-based biomarkers, integrated disease modeling and P4 medicine. It is hypothesized that deconstructing AD into multiple genetic and biological subsets existing within this heterogeneous target population will provide an effective PM strategy for treating individual patients with the specific agent(s) that are likely to work best based on the specific individual biological make-up. The Alzheimer's Precision Medicine Initiative (APMI) is an international collaboration of leading interdisciplinary clinicians and scientists devoted towards the implementation of PM in Neurology, Psychiatry and Neuroscience. It is hypothesized that successful realization of PM in AD and other neurodegenerative diseases will result in breakthrough therapies, such as in oncology, with optimized safety profiles, better responder rates and treatment responses, particularly through biomarker-guided early preclinical disease-stage clinical trials.

PRECISION MEDICINE - The Golden Gate for Detection, Treatment and Prevention of Alzheimer's Disease.

During this decade, breakthrough conceptual shifts have commenced to emerge in the field of Alzheimer's disease (AD) recognizing risk factors and the non-linear dynamic continuum of complex pathophysiologies amongst a wide dimensional spectrum of multi-factorial brain proteinopathies/neurodegenerative diseases. As is the case in most fields of medicine, substantial advancements in detecting, treating and preventing AD will likely evolve from the generation and implementation of a systematic precision medicine strategy. This approach will likely be based on the success found from more advanced research fields, such as oncology. Precision medicine will require integration and transfertilization across fragmented specialities of medicine and direct reintegration of Neuroscience, Neurology and Psychiatry into a continuum of medical sciences away from the silo approach. Precision medicine is biomarker-guided medicine on systems-levels that takes into account methodological advancements and discoveries of the comprehensive pathophysiological profiles of complex multi-factorial neurodegenerative diseases, such as late-onset sporadic AD. This will allow identifying and characterizing the disease processes at the asymptomatic preclinical stage, where pathophysiological and topographical abnormalities precede overt clinical symptoms by many years to decades. In this respect, the uncharted territory of the AD preclinical stage has become a major research challenge as the field postulates that early biomarker guided customized interventions may offer the best chance of therapeutic success. Clarification and practical operationalization is needed for comprehensive dissection and classification of interacting and converging disease mechanisms, description of genomic and epigenetic drivers, natural history trajectories through space and time, surrogate biomarkers and indicators of risk and progression, as well as considerations about the regulatory, ethical, political and societal consequences of early detection at asymptomatic stages. In this scenario, the integrated roles of genome sequencing, investigations of comprehensive fluid-based biomarkers and multimodal neuroimaging will be of key importance for the identification of distinct molecular mechanisms and signaling pathways in subsets of asymptomatic people at greatest risk for progression to clinical milestones due to those specific pathways. The precision medicine strategy facilitates a paradigm shift in Neuroscience and AD research and development away from the classical "one-size-fits-all" approach in drug discovery towards biomarker guided "molecularly" tailored therapy for truly effective treatment and prevention options. After the long and winding decade of failed therapy trials progress towards the holistic systems-based strategy of precision medicine may finally turn into the new age of scientific and medical success curbing the global AD epidemic.

Cortical-basal ganglia imbalance in schizophrenia patients and unaffected first-degree relatives.

Structural brain changes are amongst the most robust biological alterations in schizophrenia, and their investigation in unaffected relatives is important for an assessment of the contribution of genetic factors. In this cross-sectional morphometry study we investigated whether volume changes in SZ are linked with genetic vulnerability and whether these effects are separated from secondary illness effects. We compared density of grey and white matter using high-resolution 3D-anatomical MRI imaging data in 31 SZ patients, 29 first-degree relatives and 38 matched healthy controls, using Voxel-Based Morphometry (VBM) with SPM8. Volume of basal ganglia was also compared by manual segmentation. We found increased grey matter in the striatum, globus pallidus internus and thalamus and decreased grey matter in the parahippocampal and cingulate gyri both in SZ patients and relatives. Additionally, SZ patients had decreased volume of temporal, frontal and limbic grey and white matter in comparison with relatives and controls. Relatives showed intermediate values in many of these areas. Increased volume in the thalamus and parts of the basal ganglia and decreased volume of cortical areas and underlying white matter were thus associated with schizophrenia and its genetic vulnerability. These results suggest that brain morphological changes associated with SZ are in part determined by genetic risk factors and are not entirely explained by effects of medication or changes secondary to illness.

Referral for cancer genetics consultation: a review and compilation of risk assessment criteria.

BACKGROUND: There have been many papers on the diagnostic criteria for specific hereditary cancer susceptibility syndromes and the likelihood that an individual has a germline mutation in one of the various cancer susceptibility genes. To assist health care professionals in deciding when a cancer genetics consultation is appropriate, available reports were critically reviewed in order to develop a single set of risk assessment criteria. METHODS: The criteria were based on a comprehensive review of publications describing diagnostic criteria for hereditary cancer syndromes and risk to first degree relatives of cancer patients. Priority was given to diagnostic criteria from consensus statements (for example, those from the National Comprehensive Cancer Network). Expert opinion from study personnel was then used to adopt a single set of criteria from other publications whenever guidelines differed. RESULTS: Based on family history, a set of criteria was developed to identify patients at risk for a hereditary cancer susceptibility syndrome, patients with moderate risk who might benefit from increased cancer surveillance, and patients who are at average risk. The criteria were applied to 4360 individuals who provided their cancer family history between July 1999 and April 2002, using a touch screen computer system in the lobby of a comprehensive cancer centre. They categorised an acceptable number of users into each risk level: 14.9% high risk, 13.7% moderate risk, and 59.6% average risk; 11.8% provided insufficient information for risk assessment. CONCLUSIONS: These criteria should improve ease of referral and promote consistency across centres when evaluating patients for referral to cancer genetics specialists.

[Current therapy of patients with dementia]. / Aktuelle Antidementiva. Demenzkranken steht eine moderne Therapie zu.

In recent years, the efficacy of symptomatic treatment in patients with Alzheimer's disease has repeatedly been demonstrated in a number of multicenter studies. Such treatment aims both to improve the patient's cognitive abilities and to preserve his or her quality of life and ability to cope with the activities of daily life. In this way the burden on relatives and caregivers is reduced, and the need for home or institutionalized care delayed. Causally effective therapeutic strategies resulting in a cure or the delaying of pathophysiological progression are currently not available, but are being investigated in ongoing clinical and experimental studies. Presently available treatments should be initiated early on, and applied as long as needed, which requires the earliest possible clinical diagnosis by the primary-care physician. The results of initial studies reveal an effect of antidementia agents also in mixed Alzheimer's and vascular dementia, as well as vascular and lewy-body dementia. Efforts to obtain approval for these indications are underway.

[Early diagnosis and treatment of Alzheimer's disease. Implementation in the doctor's office]. / Frühdiagnostik und Therapie der Alzheimer-Krankheit. Zum Vorgehen in der Praxis.

The efficacy of antidemential agents proven in comprehensive studies and by clinical experience, now justifies an active and positive approach by the general physician to the diagnosis and treatment of patients with dementia. The proposals on how to implement diagnostic and therapeutic measures in the doctor's office comply both with medical quality criteria and the requirements for appropriateness of treatment and considerations of economy stipulated by German law. They therefore provide the basis for a modern diagnostic work-up and treatment strategy, which will also meet economical demands.