P4 Medicine or O4 Medicine? Hippocrates Provides the Answer

Diagnostic and progression biomarkers in cerebrospinal fluid of Alzheimer's disease patients

In this commentary, we address a paper published by Johnson et al. by assessing the robustness of their method to discover diagnostic biomarkers in Alzheimer's disease (AD). In addition, we examine how these newly discovered and previously discovered biomarkers, can play a role in assisting patients with AD and those at risk for developing AD, with an emphasis on the translational hurdles that accompany such discoveries.

Direct-to-consumer tests advertised online in Australia and their implications for medical overuse: systematic online review and a typology of clinical utility

OBJECTIVES

The objective of this study is to map the range and variety of direct-to-consumer (DTC) tests advertised online in Australia and analyse their potential clinical utility and implications for medical overuse.

DESIGN

Systematic online search of DTC test products in Google and Google Shopping. DTC test advertisements data were collected and analysed to develop a typology of potential clinical utility of the tests at population level, assessing their potential benefits and harms using available evidence, informed by concepts of medical overuse.

RESULTS

We identified 484 DTC tests (103 unique products), ranging from $A12.99 to $A1947 in cost (mean $A197.83; median $A148.50). Using our typology, we assigned the tests into one of four categories: tests with potential clinical utility (10.7%); tests with limited clinical utility (30.6%); non-evidence-based commercial 'health checks' (41.9%); and tests whose methods and/or target conditions are not recognised by the general medical community (16.7%). Of the products identified, 56% did not state that they offered pretest or post-test consultation, and 51% did not report analytical performance of the test or laboratory accreditation.

CONCLUSIONS

This first-in-Australia study shows most DTC tests sold online have low potential clinical utility, with healthy consumers constituting the main target market. Harms may be caused by overdiagnosis, high rates of false positives and treatment decisions led by non-evidence-based tests, as well as financial costs of unnecessary and inappropriate testing. Regulatory mechanisms should demand a higher standard of evidence of clinical utility and efficacy for DTC tests. Better transparency and reporting of health outcomes, and the development of decision-support resources for consumers are needed.

Elective genetic testing: Genetics professionals' perspectives and practices

Elective genetic testing (EGT) to identify disease risk in individuals who may or may not meet clinical criteria for testing is increasingly being offered in clinical practice. However, little is known about how EGT is currently implemented and how genetics professionals perceive this type of testing. We conducted a mixed-methods survey study to evaluate genetics professionals' perspectives and attitudes about EGT and describe the current landscape of EGT practices in the United States (U.S.) and Canada. Six clinical geneticists and 131 genetic counselors responded to the online survey, among whom 44% reported offering EGT in their practice. Over 84% of survey respondents agreed that EGT may improve health outcomes and understanding of genotype-phenotype correlations, and 85% agreed that potential risks include result misinterpretation and contribution to economic health disparities. Though most respondents felt comfortable providing pretest (77%) and post-test (86%) counseling for EGT, lack of provider resources (such as time and personnel) and prioritization of diagnostic testing were cited most frequently in free-text responses as reasons for not offering EGT. Of those offering EGT, 88% reported positive overall experiences. Qualitative analysis of open-ended questions identified benefits of EGT as expanding access to genetic testing, providing potential health benefits, and providing psychological benefits for patients. Disadvantages included prohibitive costs, limited clinical utility, and strain on resources. Overall, we found that genetics providers perceive both potential benefits and harms of EGT and that those offering this testing had generally positive experiences, although ethical reservations and practical limitations exist.

Direct-to-consumer detection of atrial fibrillation in a smartwatch electrocardiogram: Medical overuse, medicalisation and the experience of consumers

The Apple Watch Electrocardiogram (ECG) is a digital feature that detects signs of atrial fibrillation (AFib), a heart arrhythmia that can lead to stroke. Unlike AFib detection offered in a clinical setting to patients or those at higher risk, the Apple Watch ECG is a direct-to-consumer (DTC) product marketed to the healthy as a self-performed medical test. The feature is incorporated in the design as one of many applications in a multifunctional smartwatch. The Apple Watch ECG signals the movement of consumer wearables into the domain of medical devices, and the highly contested practice of AFib screening. This article examines how this technology produces new avenues for medical overuse among people who are unlikely to gain clinical benefit, and who as active consumers become medicalised via taking part in disease-specific monitoring. Interviews with Apple Watch ECG consumers suggest their strongly trust in the Apple brand is amplified by the promissory quality of screening and technical innovation. What would otherwise be a costly clinical procedure is condensed into an accessible function in a wearable device. Consequently, AFib screening loses its clinical purpose, and is instead refashioned into a component of healthy lifestyle behaviour. Repeat self-screening becomes 'bundled' with similar health monitoring practices routinised in consumer wearables. Active uptake supports a market for the product and adds to the reputation of the Apple brand such that consumers become complicit in legitimising a medical practice that has limited clinical justification.

A study of elective genome sequencing and pharmacogenetic testing in an unselected population

BACKGROUND

Genome sequencing (GS) of individuals without a medical indication, known as elective GS, is now available at a number of centers around the United States. Here we report the results of elective GS and pharmacogenetic panel testing in 52 individuals at a private genomics clinic in Alabama.

METHODS

Individuals seeking elective genomic testing and pharmacogenetic testing were recruited through a private genomics clinic in Huntsville, AL. Individuals underwent clinical genome sequencing with a separate pharmacogenetic testing panel.

RESULTS

Six participants (11.5%) had pathogenic or likely pathogenic variants that may explain one or more aspects of their medical history. Ten participants (19%) had variants that altered the risk of disease in the future, including two individuals with clonal hematopoiesis of indeterminate potential. Forty-four participants (85%) were carriers of a recessive or X-linked disorder. All individuals with pharmacogenetic testing had variants that affected current and/or future medications.

CONCLUSION

Our study highlights the importance of collecting detailed phenotype information to interpret results in elective GS.

Defining the Skin Cellular Community Using Single-Cell Genomics to Advance Precision Medicine

Single-cell genomics has revolutionized biological science, enabling high-resolution analysis of human tissues. The ability to demonstrate the role and function of distinct cell types comprising human tissues paves the way for a new understanding of cellular pathways, interactions, and future research directions. The skin, easily accessible and possessing a diverse and complex role in defending us both physically and immunologically from the outside world, lends itself ideally to single-cell genomics analysis. Here, we outline the benefits of single-cell RNA sequencing while also highlighting the challenges in achieving a meaningful result from its use. Key milestones relating to the study of skin in this way are introduced, covering both healthy and diseased states, and we discuss the potential promise of single-cell RNA sequencing to result in tangible medical advances, with a particular focus on precision medicine.