Exploring the Skin Brain Link: Biomarkers in the Skin with Implications for Aging Research and Alzheimer's Disease Diagnostics.

Neurodegenerative diseases, including Alzheimer's disease (AD), are challenging to diagnose. Currently the field must rely on imperfect diagnostic modalities. A recent study identified differences in several key bio-mechano-physiological parameters of the skin between AD patients and healthy controls. Here, we visually align these differences with the relevant histological, aging, and embryological paradigms to raise awareness for these potential biomarkers. In a study conducted by Wu et al., a series of n = 41 patients (n = 29 with AD and n = 12 healthy controls) were evaluated, demonstrating that AD patients exhibit a less acidic skin pH, increased skin hydration, and reduced skin elasticity compared to healthy controls. We constructed a visual overview and explored the relevant paradigms. We present a visual comparison of these factors, highlighting four paradigms: (1) the findings emphasize a shared ectodermal origin of the brain and the skin; (2) functional systems such as micro-vascularization, innervation, eccrine excretory functions, and the extracellular matrix undergo distinct changes in patients with AD; (3) the human skin mirrors the alterations in brain stiffness observed in aging studies; (4) assessment of physiological features of the skin is cost-effective, accessible, and easily amenable for monitoring and integration with cognitive assessment studies. Understanding the relationship between aging skin and aging brain is an exciting frontier, holding great promise for improved diagnostics. Further prospective and larger-scale investigations are needed to solidify the brain-skin link and determine the extent to which this relationship can be leveraged for diagnostic applications.

Diagnostic Test Utilization Management Strategies as an Opportunity for Equitable Access to Molecularly Informed Clinical Care.

BACKGROUND: Companion diagnostics are an essential component of oncology. Timing, cost, and adaptability to new drug/biomarker approvals represent challenges in assuring value-based care. Overcoming these challenges requires strategies for equitable access and efficient integration. METHODS: Based on prior laboratory improvements and payor policy implementations, we define equitable access in laboratory testing and conceptualized a framework for initiatives that optimize diagnostic performance. RESULTS: We define equitable access as an imperative goal seeking to remove disparities that may arise due to financial hardships, geographical isolation, cultural differences, or other social determinants of health. We distinguish (a) utilization, as the practice pattern of ordered tests, (b) utilization management, as the evidence-based guidance of the utilization decisions, and (c) utilization management strategies, defined as the tools and techniques used to influence decision-making. These 3 dimensions establish a standardized vocabulary to clarify equitable alignment of strategies in specific care pathways. Alignment of logistic, administrative, and financial incentive structures is paramount when creating sustainable personalized care pathway programs. CONCLUSIONS: Strategies to accomplish equitable and meaningful use of diagnostic tests can help enhance access to timely and accurate diagnoses, ultimately leading to improved patient outcomes.