A new analysis from UC San Francisco argues that diagnostics are being overlooked both in the United States and around the world. This is slowing progress against major diseases, despite rapid advances in targeted therapies and precision health.
The authors note that nearly half of the world’s population lacks adequate access to diagnostics. These tests receive less investment for research and development, as well as lower insurance reimbursement than drugs, and this is creating barriers to innovation.
“Most people can easily understand how a new drug or surgery might help a patient,” said Kathryn Phillips, Ph.D., a professor of Health Economics in the School of Pharmacy at UC San Francisco and the lead author of the study, which appears in Science. “But the tests that guide medical decisions are just as critical.”
When treatments advance faster than tests
Advances in therapies are outpacing the development of the tests that are needed to guide their use. For example, many people do not respond to GLP-1 drugs for obesity and diabetes, but few tests exist yet to predict which patients will benefit.
Alzheimer’s is another example. New drugs exist to slow disease progression, but the blood tests that could match patients to the most beneficial drugs cost around $1000 and, unlike the drugs, which cost $30 000 a year, they rarely qualify for insurance coverage. This can leave doctors to make medical decisions without the necessary information. Some patients may not get the right treatments, and others may not get any treatments.
Regulatory misalignment and policy fixes
Even though they are essential to care, these diagnostic tests are often handled apart from the treatments they support. The FDA reviews tests differently than drugs, and insurers pay for them differently. Drugs are also much more likely to receive expedited FDA review than tests.
“Regulatory and payment policy should evolve in tandem with scientific and technological advances,” said Robert M. Califf, MD, former commissioner of the FDA and co-author of the paper.
“The current misalignment between how we evaluate diagnostics for consideration of allowing marketing and the system for reimbursement decisions about diagnostics versus drugs leaves powerful tools on the shelf and provides inadequate data to make good decisions about which diagnostic tools should be eschewed for lack of benefit in the real world.”
The authors say there are clear steps policymakers can take to fix these gaps, including reviewing tests and treatments together, streamlining approvals for tests, and improving how diagnostics are evaluated and paid for.
“Our hope is that this work helps people – patients, policymakers, insurers, and researchers – recognise diagnostics as essential to good health care – and not just an afterthought,” said Phillips, who directs the UCSF Center for Translational and Policy Research on Precision Medicine (TRANSPERS) and is a member of the Philip R. Lee Institute for Health Policy at UCSF.
Photoreceptor cells in the retina. Credit: Scientific Animations
A new Yale School of Medicine (YSM) study has uncovered surprising new details about how our eyes process what we see.
When we look at something, our visual system breaks down different aspects of the scene – such as colour, contrast, and motion – and processes those components separately. It’s called parallel visual processing and it’s what allows our brains to work out what we’re seeing so quickly.
This separation of information starts in the retina, and scientists have thought that separation is maintained as the information travels through the visual system. But in a study published in Neuron, researchers have found that information channels are more integrated than previously thought. This may help cells process weak visual signals, such as low-light conditions, the researchers say.
“We found that while different channels can deliver their own features, they’re also interconnected by underlying electrical circuitry,” says Yao Xue, PhD, a postdoctoral fellow in the department of ophthalmology and visual science at YSM and the study’s first author.
Untangling bipolar cell signals in the retina
The rods and cones in our retinas detect light and transmit signals to a type of neuron called bipolar cells. In these cells, visual components such as night, day, colour, shape, and contrast begin to separate into more than a dozen parallel channels.
But when researchers zoomed in on bipolar cell synapses, they found these information channels intermingle.
Neurons have two types of synapses: chemical and electrical. At chemical synapses, neurons release chemical messengers known as neurotransmitters that bind to the recipient cell. Electrical synapses, also known as gap junctions, facilitate communication with electric currents. Bipolar cells primarily communicate through chemical synapses.
The researchers found, however, that in the mouse and human retinas they studied, electric synapses were integrating most of those seemingly separate bipolar cell information channels. When the scientists electrically stimulated one bipolar cell, instead of seeing a localised release of neurotransmitters just within that cell’s channel, they observed cloud-like patterns of signalling – suggesting crosstalk among the different types of cells.
“When we stimulated one bipolar cell, many bipolar cells released neurotransmitters,” says Z. Jimmy Zhou, PhD, Professor of Ophthalmology and Visual Science and principal investigator.
“If the signal is already very weak and is divided into several channels, there isn’t much left for each channel to process. The integration is particularly useful for detecting low contrast signals or signals from very small objects.”
To their surprise, they also identified one type of bipolar cell, called BC6, that drove this signalling. These cells generated strong signals that travelled through the parallel channels in a hierarchical manner. “People had assumed that the different types of bipolar cells were more or less autonomous,” Zhou says. “But we found a driver among all these cell types that creates this network with a hierarchy.”
Having distinct parallel channels can help bipolar cells divide and conquer as they process different parts of a visual signal. The linkage of these channels through electrical synapses, on the other hand, could help the cells process weak visual signals, the researchers say.
“If the signal is already very weak and is divided into several channels, there isn’t much left for each channel to process,” says Seunghoon Lee, PhD, a research scientist in the department of ophthalmology and visual Science at YSM and co-corresponding author of the study. “The integration is particularly useful for detecting low contrast signals or signals from very small objects.”
“And the cells aren’t cooperating in a random way,” adds Xue. “There’s a commander within them – BC6 – that leads them in relaying signals to the downstream target.”
Recording from hard-to-reach cells
For the study, the researchers used several methods to study the synaptic circuitry of bipolar cells, including imaging to observe the cells’ activity and how they released and responded to neurotransmitters, as well as stimulating activity in bipolar cells and recording responses in recipient cells.
One challenge of studying signal transmission in bipolar cells is that they live in the middle of the retina. Previous studies have cut the retina into slices in order to access the cells, but that can disrupt the synaptic circuitry. In the new study, however, the researchers were able to apply the dual patch-clamp technique in fully intact mouse retinas. This method uses electrodes to stimulate activity in different types of bipolar cells and records the responses of recipient cells.
“No other lab in the world has been able to pull off these kinds of recordings systematically,” says Zhou. “It is a tour de force of Yao Xue’s PhD thesis work, pairing an innovative approach with exceptional electrophysiological skill.”
The team then repeated the experiment in human retinas, which they obtained from the department of pathology’s Legacy Tissue Donation Program. These are the first experiments of their kind in an intact human retina, the YSM researchers say.
New global study using data from the National Joint Registry, estimates that modern hip replacements could last at least 30 years
Photo by DanR. CC BY-NC-SA-2.0
A major international study led by researchers who have used extensive data from the NJR estimates that modern total hip replacements, those using today’s more advanced bearing surfaces, are likely to last over 30 years in 92% of patients. This new finding marks a significant improvement in long term implant longevity and durability, compared with previous generations of medical implant devices.
Published on 26 February 2026, the research represents the largest and most contemporary analysis of hip replacement conducted to date. The study was a global collaboration including data contribution from eight joint registries. The data of just under two million hip replacement procedures were analysed, with the NJR accounting for almost two-thirds of that data. Registry data were combined with evidence from 29 long term clinical studies, across 18 countries.
Data was included from adult patients undergoing primary hip replacement with contemporary bearing surfaces: highly cross‑linked polyethylene (XLPE), ceramic‑on‑XLPE, or third‑ and fourth‑generation ceramic‑on‑ceramic articulations. Only implants that are still in routine clinical use were included, ensuring the study reflects modern practice, rather than historic device performance. Across all registries, cases were followed for a minimum of 10 years, with implant survival tracked until first all‑cause revision. All three material types demonstrated similarly high survivorship.
The results of the study provide patients with reassurance in consideration of the commonly asked question “How long will my hip replacement last?” It is encouraging to know that modern hip replacements could last decades.
With regard to previous research on implant longevity, a 2019 study into hip replacement longevity which was supported by the NJR, suggested that over half, ie. 58% of hip replacements lasted 25 years, but those estimates were based on some implants made of materials that are no longer widely used. In 2022, another review of NJR data was conducted to enable further understanding of implant longevity, which produced the paper: ‘How long revised and multiply-revised hip replacements last?’ You can read more on that here.
Study shows that income remains lower for up to 10 years after diagnosis
Photo by Sydney Sims on Unsplash
A diagnosis of depression in connection with hospital treatment can have long-term consequences for personal finances. This is shown in a new registry-based study from the Department of Public Health, University of Southern Denmark, which follows nearly five million people in Denmark over time.
The study found that income is around 10% lower 10 years after diagnosis compared with people without depression, and the gap does not disappear. At the same time, the income loss for depression is greater than for several physical illnesses such as stroke and breast cancer.
Mental illness has the greatest financial impact
The study compares depression, alcohol use disorder, stroke and breast cancer. Income falls after illness in all four groups, but the decline is greatest for mental disorders.
“We see that mental disorders affect not only health, but also people’s economic life course to a considerable extent,” says Emily K. Johnson, PhD Student at the Danish Centre for Health Economics, Department of Public Health, University of Southern Denmark.
She is first author of the study, which has been published in JAMA Health Forum.
“The income loss grows over time and can still be measured 10 years later. Even though mental disorders are more common in women, losses are generally greater for men,” Emily K. Johnson explains.
Not just a temporary loss
While earlier studies have often focused on short-term sick leave, the new study shows that income loss persists and in many cases grows over time.
– It is not only about being away from work for a period. We see changes in the entire income trajectory, says Emily K. Johnson.
This may, among other things, reflect reduced ability to keep a job, change jobs or progress in a career.
May reinforce social inequality
Income loss is greatest among people in the middle of working life, when earnings would normally be increasing. At the same time, the loss grows over time for younger people.
“If you are affected early in your career, you may lose your footing in the labour market. That can be difficult to recover later,” says Emily K. Johnson.
People outside the labour market are also hit particularly hard. For them, illness may make it even harder to enter employment. The findings therefore suggest that illness can reinforce existing social inequality.
Income falls before the illness is registered
Income already begins to decline in the years before people receive a diagnosis of depression in hospital care. This suggests that the consequences begin before the illness is formally registered and treated.
The study includes people who had contact with a hospital, either as inpatients or outpatients, including psychiatric hospital care. People treated only by their general practitioner or by private psychologists or psychiatrists are not included.
“This suggests that the course of illness starts earlier and that the consequences for working life emerge gradually,” Emily K. Johnson explains. Job loss, income loss and poor mental health can reinforce one another over time,
The study is based on Danish registry data and includes all non-retired residents aged 18 to 65 between 2000 and 2018. People with illness were compared with similar people without a diagnosis, matched on factors including age, sex, education and income, and baseline health.
Income was measured as disposable income, meaning post-tax income including wages, transfers and capital income.
Can inform health policy priorities
According to the researchers, the findings can help improve decision-making in health and social policy.
“Priority setting should not be based only on how many people become ill, but also on how illness affects people’s working lives and finances, especially for those early in their careers,” says Emily K. Johnson.
The study adds new knowledge by comparing mental and physical illnesses using the same method, making it possible to assess their relative consequences.
Limitations
The study includes only people who had contact with a hospital and therefore does not cover everyone with depression. At the same time, it cannot establish cause and effect with certainty, especially in the case of mental disorders which are difficult to measure. In addition, only people who survive the course of illness are included in the analyses of income over time.
Levels of cortisol, often referred to as the “stress hormone,” typically peak in the early morning hours, preparing the body for the day’s challenges by increasing alertness and energy levels, and gradually decline throughout the day, reaching their lowest point around midnight. New research in Nursing Open found an approximately two-fold increase in salivary cortisol levels at midnight in nurses working double shifts compared with those working single shifts.
The study included 52 female nurses, working in rotating shifts. The elevated salivary cortisol levels observed in double-shift workers at midnight suggest that prolonged work schedules are associated with alterations in normal cortisol patterns.
“Our findings indicate that extended shift schedules may be associated with alterations in the circadian pattern of cortisol, reflecting increased physiological strain in nurses working prolonged hours,” said corresponding author Fadime Ulupınar, RN, MSc, of Erzurum Technical University, in Turkey.
Meta-analysis including millions of middle-aged to older adults supports recommended activity and sleep duration to reduce dementia risk
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Regular physical activity and getting the recommended amount of sleep may reduce dementia risk later in life, according to a new study by Akinkunle Oye-Somefun and colleagues of York University, Canada, published April 8, 2026 in the open-access journal PLOS One.
An estimated 55 million people live with dementia worldwide, and both its prevalence and cost are expected to increase, with global costs projected to reach $2 trillion dollars by 2030. Current treatments for preventing or treating dementia have limited efficacy; therefore, public health efforts have also aimed at healthy lifestyle factors to reduce the risk of dementia before symptoms occur. Healthy behaviours such as regular physical activity and good sleep hygiene are known to support cognitive health; however, there remains a need to better understand their relationship to dementia.
In this systematic review and meta-analysis, researchers analysed data from 69 prospective cohort studies representing millions of community-dwelling adults aged 35+, to see if there was a link between the development of dementia and three lifestyle behaviours: physical activity, sedentary behaviour, and sleep duration. Each of the observational studies recorded behaviours of cognitively healthy participants, then followed up at a later timepoint to report subsequent rates of dementia.
Overall, the meta-analysis found that regular physical activity, less sedentary time, and appropriate nightly sleep (7–8 h) were associated with a lower subsequent risk of dementia. Regular physical activity was associated with an average 25% lower risk of dementia among the 49 studies analysed; however, the researchers note that there was considerable heterogeneity between the studies.
Too little sleep (< 7 h) or too much sleep (> 8 h) was associated with an 18% and 28% higher subsequent risk of dementia, respectively, compared to optimal nightly sleep of 7–8 hours, though there was again considerable heterogeneity among the 17 studies analysed. Prolonged sitting (> 8 hours per day) was associated with a 27% higher risk of dementia among the three relevant studies analysed.
The study is consistent with and expands on previous research, using a large, diverse population with long follow-up times. While the study design cannot show any causative link between physical activity, sleep and dementia, the findings suggest an association between adherence to recommended physical activity and sleep levels in middle- and older-age adults and lowered dementia risk later in life.
The authors add: “Dementia develops over decades, and our findings suggest that everyday behaviours such as physical activity, time spent sitting, and sleep duration may be linked to dementia risk. Understanding how each of these behaviours relates to risk over time may help researchers identify opportunities to support brain health across the life course.”
“Separately, one aspect I personally found most interesting while conducting the study was the relatively limited evidence base on sedentary behaviour. Despite growing recognition that prolonged sitting is distinct from physical inactivity, we found only a small number of cohort studies examining its relationship with dementia risk. This highlights an important gap for future research.”
Current clinical guidelines stress that lower LDL cholesterol levels significantly reduce the risk of major cardiac events. Essential strategies for treatment include heart-healthy lifestyle changes and pharmacological interventions using statins, ezetimibe, and PCSK9 inhibitors. Early intervention is vital, as the cumulative exposure to high cholesterol over time – often termed “LDL years” – determines the onset of vascular disease. But a major question has remained as to whether more aggressive lip-lowering targets is worth the potential side effects such as kidney damage.
Now, a new clinical trial published in NEJM provides evidence that an intensive target of less than 55mg/dL is superior for preventing secondary complications. In the Ez-PAVE trial, researchers in South Korea investigated whether this more intensive provided better protection than the conventional goal of less than 70mg/dL. The study found that patients in the intensive group experienced a significant reduction in cardiovascular events over a three-year period. The researchers conclude that their findings support stricter lipid-lowering guidelines, which can safely and effectively improve long-term patient outcomes.
In the analysis of data from the Health and Retirement Study, a nationally representative sample of older US adults, optimism was assessed using the validated Life Orientation Test-Revised in 9071 cognitively healthy individuals within 2 years of obtaining each person’s first measure of cognitive function. Dementia was assessed during up to 14 years of follow-up.
A 1-standard deviation increase in optimism was associated with a 15% lower risk of developing dementia, after adjusting for age, sex, race/ethnicity, education, depression, and major health conditions.
“Identifying optimism as a protective psychosocial factor highlights the potential value of optimism in supporting healthy aging,” the authors wrote.
Strong evidence ties early language difficulties to later adjustment challenges. Can environmental factors make these problems worse? In a new study, FAU researchers, in collaboration with Aarhus University in Denmark, find that unsupervised or “solo” screen time worsens the behavioural and emotional challenges confronting young children with limited language skills. A total of 546 4- to 5-year-old children from 24 childcare centres in Denmark were followed for six months. Investigators assessed their language abilities, behavioural adjustment and the amount of time the children spent watching screens alone.
The study findings, published in the journal Research on Child and Adolescent Psychopathology, found that solitary screen time acts as an amplifier, exacerbating conduct problems in children with poor communication skills and low productive vocabulary. The results highlight the critical role of the home learning environment in early childhood development. For children who struggle with language skills, time spent alone with a screen is time not spent mitigating risks through healthy social engagement with parents or friends.
Early problems with language can have a lasting negative impact on social and emotional development. Building on this foundation, a new groundbreaking study from Florida Atlantic University and Aarhus University in Denmark tests the hypothesis that unsupervised, solitary screen time during early childhood increases the likelihood that language difficulties will lead to socioemotional difficulties.
The study, published in Research on Child and Adolescent Psychopathology , found that pathways from poor communication skills and low productive vocabulary to later adjustment problems were particularly strong among preschool- and kindergarten-aged children who averaged at least 10 to 30 minutes of solitary screen time per day across the course of a week.
Study participants were 546 4- and 5-year-olds (264 girls, 282 boys) attending 24 population-based childcare centers across 13 municipalities in Denmark. Teachers completed assessments twice of child adjustment difficulties, such as conduct and emotional problems, over the course of about six months during a single school year. At the outset, teachers administered standardized tests of child language abilities, including communication skills and productive vocabulary. Parents reported on solitary screen time, which was defined as the average number of hours per week that children spent alone viewing handheld devices or television, excluding screen time supervised by or consumed with an adult.
Consistent with several previous studies, there were longitudinal associations from oral language problems to later adjustment difficulties. Across the six-month period, poor communication skills and high levels of solitary screen time separately predicted escalating emotional difficulties.
Unique to this study was the finding that solo screen time magnified problems arising from language difficulties. Associations from low productive vocabulary and poor communication skills to increases in conduct problems were strongest among children whose parents reported that their children were well above average in solitary screen time exposure.
“Unsupervised screen time forecloses opportunities for social engagement that might mitigate the behavioral risks that follow from language problems,” said Brett Laursen, Ph.D., senior author and a professor of psychology in FAU’s Charles E. Schmidt College of Science.
Laursen uses an economics model to explain the results. Economists define opportunity costs as losses attached to a choice. If an adult stays up late with a book, the opportunity cost of reading is a good night’s sleep.
“The opportunity costs of solitary screen time can be particularly steep for vulnerable youth. Children have a finite number of free time hours in a day,” said Laursen. “Every hour a child spends alone with a device is an hour they aren’t engaged in social interactions that boost language skills. It is an hour not spent practicing the social and emotional skills required to build friendships. Screens don’t demand compromise, sharing or dialogue – the exact skills that children with communication difficulties need to practice.”
Young children learn language from in-person interactions – very little is acquired from video screens. Further, electronic media cannot replace the rich social experiences children gain from play and engagement with peers.
“Young children with limited language skills are already at risk for social and emotional challenges,” said Molly Selover, lead author and an FAU doctoral student in psychology. “There is little reason to expect that screens help children overcome the adaptive challenges posed by oral language problems and many reasons to suspect that they make matters worse.”
Excessive screen use by young children is widespread: the World Health Organization recommends no more than one hour per day for children ages 2 to 5, yet a global review found that two-thirds of households exceed this limit. In the United States, about half of young children spend more than two hours a day on screens during the week, with even higher use on weekends. Of course, both content and supervision matter.
For children ages 2 to 5, the American Psychological Association encourages parents to limit screen time to no more than one hour per day and to co-view and interact with their children during this time rather than using the screen as a babysitter. They also note that the quality of the content on screens is extremely important, perhaps more important than the total amount of time spent viewing.
The authors say that high caliber content has documented benefits for children, especially as children get older. Unfortunately, when left to their own devices, many young children prefer fast-paced, brief and highly stimulating content, some of which may be age-inappropriate.
“Electronic media is as an integral component of the home learning environment; many children spend more time with tablets and phones than with toys, books and friends,” said Selover. “Like other home environment risks, solitary screen time poses a unique peril to young children with heightened vulnerabilities. Adults tend to think of screens as pleasant distractions and may use them as convenient babysitters. But for preschool children with language vulnerabilities, unsupervised screen time is not benign – it can be an active barrier to well-being.”
The authors acknowledge that their findings may not be popular. Screens are a ubiquitous part of everyday life. Nevertheless, they encourage parents to carefully scrutinize how young children engage screens.
“The findings matter because they show that an all-too-common environmental risk – elevated solitary screen time – can worsen behavioural and conduct challenges for children who face an already difficult developmental path,” Selover said.
Targeting immune cells with cold plasma to speed healing and enhance surgical outcomes
A handheld cold atmospheric plasma device. Frontiers in Dermatology, 2022. https://doi.org/10.3389/fonc.2022.918484
Cold plasma devices are increasingly used across surgical procedures, including skin rejuvenation, scar remodeling, liposuction and diabetic wounds. A recent study from Thomas Jefferson University found that using an FDA-approved cold plasma device can enhance tissue healing after surgery by activating a wound-healing response.
“Anecdotally, after receiving cold plasma treatment for dermatology procedures, patients have reported firmer and ‘younger’ feeling skin in the treatment area,” according to senior author Theresa Freeman, PhD. While several published reports support the idea that cold plasma could activate healing in cells, there was little evidence in living organisms. This motivated Dr Freeman and her team to figure out what was happening when injured muscle tissue was treated with a cold plasma device.
“We found that cold plasma produces bursts of ‘reactive species,’ which are molecules that can directly communicate with the immune cells and trigger them to start the healing process,” says Carly Smith, a recently graduated doctoral student in Dr Freeman’s lab and first author on this study.
Researchers treated rat surgical wounds with cold plasma, and within six hours, neutrophils increased in number and began repairing the wound. Cold plasma seemingly uses the natural wound-healing response to its advantage.
To understand how this spike in neutrophils could affect healing, the researchers compared cold plasma-treated to untreated rat muscle tissue at different time points. Repairing injured muscle tissue involves replacing it with new muscle or fat. Dr Freeman notes, “After six hours, plasma-treated tissue increased the expression of pathways and genes related to repairing and restoring muscle tissue. Fourteen days after treatment, plasma reduced the accumulation of fat in the healing muscle tissue. This could explain why patients said their skin feels firmer after cold plasma treatment.”
In addition to promoting healing, cold plasma can kill bacteria. In future studies, Dr Freeman hopes to combine cold plasma with standard-of-care antibiotics used in surgery to boost the healing process and prevent infections. “If we can show this combined treatment is effective, it can be used by clinicians to improve surgical outcomes,” says Dr Freeman.
