Transforming Mental Illness Diagnosis and Treatment with Biomarkers

In this article I discuss potential use of biomarkers to diagnose and treat psychiatric disorders, particularly depression. Research is underway to identify these which could improve diagnosis and treatment, though concerns about cost, insurance, and privacy persist. Adequate funding for research is crucial.

This information is current as of the date of original publication or update but may have changed by the time you read this. Do not use this information for diagnosis or treatment purposes. Before making health decisions, discuss with a qualified healthcare professional.

Imagine you consult a physician for a problem. The doctor asks you questions and examines you. Then you have blood tests, cultures, X-rays,a CT scan or MRI. You hope these tests show what is “wrong” so the doctor can treat you.

But what if all the tests are “normal”? Normal tests suggest that your symptoms may be due to a cause for which there is no biomarker.

A biomarker is a diagnostic test that indicates a specific disease or condition.

biomarker-A biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease.

Both physicians and patients would like a biomarker for every disease. But many common conditions do not yet have a biomarker.

These include migraine, fibromyalgia, irritable bowel syndrome, Parkinson’s disease, many skin conditions, Alzheimer’s dementia, depression, and other psychiatric disorders.

a female physician talking to a male patient

For these disorders, physicians make a “clinical diagnosis”.

clinical diagnosis-The process of identifying a disease, condition, or injury based on the signs and symptoms a patient is having and the patient’s health history and physical exam

Much of medical research is devoted to finding biomarkers for these and other conditions. This article from KFF focuses on finding biomarkers for psychiatric disorders, especially depression. Such tests could be helpful not only for diagnosis but also for guiding therapy.

But there are potential downsides, like cost, insurance coverage, privacy, and potential discrimination, as explained in the article.

Psychiatrists’ Use of Biomarkers Could Open a New Window Into Mental Health Diagnoses

by Jamie Ducharme, March 17, 2026

Amanda Miller was 30 and pregnant with her second child in Hershey, Pennsylvania, when she developed depression. After she gave birth, her depression worsened. It was joined by a slew of unexplained health problems.

Miller, a neuroscientist, said she saw several psychiatrists and got prescriptions for drug after drug. Over two years, she tried four antidepressants and two antipsychotics. None of that helped — until her primary care doctor noticed high levels of an autoimmune marker in her blood.

A specialist then ran “every test in the book,” Miller said. Eventually, she was diagnosed with the autoimmune disease lupus and prescribed an inflammation-lowering steroid. Some of her symptoms let up within hours. Her depression subsided not long after.

“I was convinced it was a placebo effect,” Miller said, “but then it kept working.”

Had inflammation been contributing to her mental health problems all along? Miller thinks so, although she can’t know for sure. Her psychiatrists never raised that possibility, she said.

Laboratory vs Clinical Diagnosing

In most medical specialties, doctors can confirm whether to pursue a type of treatment through tests, such as blood work, imaging, and biopsies. Mental illnesses, however, have historically been diagnosed and treated based on outward symptoms. That could change.

The American Psychiatric Association in a January paper included ideas for how it might incorporate biomarkers — biological indicators of mental illness that could show up on diagnostic tests — into future versions of its Diagnostic and Statistical Manual of Mental Disorders.

Diagnostic and Statistical Manual of Mental Disorders.

The DSM, sometimes called “psychiatry’s bible” because of its influence in the field, provides criteria for diagnoses. It’s used by clinicians assessing patients and by insurance companies deciding whether to cover care.

‘Coordinated’ Research Needed

Psychiatric biomarkers are not ready for widespread use yet, the paper emphasized. Scientists have researched the topic for decades, with little to show for it.

More research is needed to prove these metrics are valid and reliable enough to be used in patient care, the APA’s paper said, and other researchers have raised questions about how their use could affect health care costs, insurance coverage, and patient privacy.

Adding biomarkers to the DSM would be “a very big deal,” said Jonathan Alpert, an author of the January paper and vice chair of the APA’s Future DSM Strategic Committee.

Access to test results, along with symptoms, could streamline insurance coverage decisions and help clinicians make faster and more accurate diagnoses and treatment recommendations, he said. If patients’ biology suggested they’d respond better to one treatment than another, their doctor could waste no time in starting there.

A Prescribing “Crapshoot”

Currently, prescribing psychiatric medications can be “a bit of a crapshoot,” with clinicians unable to predict whether they will work for a particular patient, said Matthew Eisenberg, director of the Center for Mental Health and Addiction Policy at the Johns Hopkins University Bloomberg School of Public Health.

In a seminal, early 2000s trial funded by the National Institute of Mental Health, about 30% of the study’s participants with depression saw symptoms disappear with their first antidepressant treatment. That study is still one of the most robust antidepressant trials conducted — although researchers have more recently argued that fewer people are cured by these medications than its results suggest.

9 different medication pills and capsules of various colors

Such a trial-and-error approach can lead to ineffective and unnecessary prescriptions, a topic of attack by proponents of the Make America Healthy Again movement, spearheaded by Health and Human Services Secretary Robert F. Kennedy Jr. Kennedy has been especially critical of antidepressants, having linked them to violence after a mass shooting without evidence and blaming doctors for overprescribing medications for children.

HHS is analyzing psychiatric diagnosis and prescription trends and evaluating alternative mental health treatment approaches, with a particular focus on children, spokesperson Emily Hilliard said in a statement. Hilliard did not respond to a question about Kennedy’s previous comments.

Biomarkers are already used to guide treatment in other medical disciplines, such as oncology. Arizona, Georgia, Kentucky, Texas, and more than a dozen other states require insurers to cover such testing. Blood and imaging tests are now used to help diagnose Alzheimer’s disease as well.

A Future for Psychiatric Biomarkers

The APA included in its article a variety of ways psychiatric biomarkers could be used in the future — such as testing for brain activity, genetic profiles, or immune markers associated with certain psychiatric conditions, including schizophrenia and substance use disorders.

In depression, for example, about a quarter of patients have elevated levels of an inflammatory protein, called C-reactive protein, that can be found through a blood test.

Research has shown that people with high levels of this protein seem to respond better when given drugs that alter dopamine levels in the brain, rather than using only selective serotonin reuptake inhibitors, or SSRIs, a common type of antidepressant.

C-reactive protein still needs to be “robustly validated” as a biomarker, but it’s among the most promising currently under investigation.

APA

A “coordinated, well-funded” research effort is needed to achieve such validation, the APA wrote — a tenuous prospect since the Trump administration slashed funding for research.

The National Institute of Mental Health alone had at least 128 grants, worth almost $173 million, canceled in 2025, according to a research letter in the journal JAMA. Though some grants have since been restored, researchers relying on federal money still fear their work is vulnerable to cuts.

“There’s a great need for continued, active funding of research related to mental health,” Alpert said, but scientists will have to grapple with “uncertainties of the funding landscape.”

Ripple Effects on Coverage, Costs

Health care costs tend to be higher among patients with poorly controlled mental illnesses, due to expenses like hospital visits, outpatient appointments, and prescriptions. Some research suggests biomarker testing could save money by landing on the right treatments faster and avoiding some of these costs.

One modeling study estimated that testing to look for genetic components that may influence a drug’s effectiveness could save the Canadian health system $956 million over 20 years if used among adults with major depression in British Columbia. Another study, by Spanish researchers, found that such testing reduced costs for most of the 188 participants with serious mental illness.

Whether the same would be true in the U.S. health care system is unknown. In the short term, Johns Hopkins’ Eisenberg said, an approach that uses biomarkers could raise health care spending due to the costs of testing.

Insurers may decline to cover pricey biomarker tests, It takes a while for new science to be proven safe and effective,
And once it is, insurance companies don’t cover it immediately.”

Matthew Eisenberg, Johns Hopkins

“The Beginning of a Revolution”

Some researchers have raised concerns that insurers or employers could discriminate against people whose biological profiles suggest they’re at risk of developing serious neuropsychiatric conditions.

It’s a “critical moment” to consider legislative approaches to protect patients and train clinicians about how to appropriately use these tools, said Gabriel Lázaro-Muñoz, a member of Harvard Medical School’s Center for Bioethics.

“I do not think that the field of psychiatry is currently ready to manage this,” he said.

The mental health system isn’t ready to “jump in with both feet,” said Andrew Miller, a professor of psychiatry and behavioral sciences at the Emory University School of Medicine, who studies inflammation-related depression. But the APA’s embrace of biomarkers signals “the beginning of a revolution,” he said.

“This is a recognition … that what we’ve done up to this point has not been good enough,” Miller said. “And we can do better.”

KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

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This story can be republished for free (details).KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

Subscribe to KFF Health News’ free Morning Briefing.

This article first appeared on KFF Health News and is republished here under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Depression

Depression is common among people who have a chronic disease such as cancer or diabetes. Fortunately, depression is treatable even if you have another medical illness or condition. Learn more about chronic disease and depression: Caring for your mental health #shareNIMH

Biomarkers in Cancer Care

Biomarker testing is a way to look for genes, proteins, and other substances (called biomarkers or tumor markers) that can provide information about cancer. Each person’s cancer has a unique pattern of biomarkers.

Some biomarkers affect how certain cancer treatments work. Biomarker testing may help you and your doctor choose a cancer treatment for you.

There are also other kinds of biomarkers that can help doctors diagnose and monitor cancer during and after treatment. To learn more, visit the Tumor Markers fact sheet.

Biomarker testing is for people who have cancer. People with solid tumors and people with blood cancer can get biomarker testing.

The FDA-approved blood tests for diagnosing Alzheimer’s disease

In May 2025, the U.S. Food and Drug Administration (FDA) approved the first blood test as a tool to help diagnose Alzheimer’s disease. The test is called Lumipulse.

The test measures certain proteins, including a specific form of the tau protein. This can indicate amyloid plaques in the brain, a protein that is considered the hallmark sign of Alzheimer’s disease.

This blood test, along with other diagnostic tools can help diagnose Alzheimer’s disease. While the blood test can detect changes even before memory problems begin, it is only recommended for use in people showing symptoms of Alzheimer’s disease.

The test is still being refined and can’t diagnose Alzheimer’s disease on its own. 

What to Remember from this Post

I learned from the KFF article and the references, did you? What are your takeaways from what you read? Here are some to consider.

  • Doctors use laboratory tests and imaging to supplement information gleaned from talking to and examining patients.
  • Biomarkers for common conditions make diagnosis easier and more precise, and help guide therapy.
  • Discovery of biomarkers for other serious conditions will help patients get earlier diagnosis and more effective treatment. More research is needed.
  • New medical discoveries introduce trade-offs in cost, payment, benefit, and potential misuse.

How will you use what you’ve learned? How may you apply this information to a current or future health concern?

What more information do you need and where will you find it?

a stethoscope, a red heart and a heart ekg tracing
exploring the HEART of HEALTH

Exploring the HEART of Health

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Dr. Aletha

Justice Amy Coney Barrett-“Standing Up for the Law”

I’m writing here about the United States Supreme Court, with nine justices including Amy Coney Barrett, plays a crucial role in the judiciary. Barrett, a conservative appointee, recently discussed her experiences and perspectives on the court, emphasizing the need for judges to adhere to the law despite external pressures, while facing public scrutiny and protests.

The United States Supreme Court is the highest level of the judiciary branch of the United States government. Currently, there are 9 justices on the court.

Out of 115 justices that have served on the court, only six have been women. The first woman justice, Sandra Day O’Conner, was appointed in 1981. She was followed by Ruth Bader Ginsburg. Now serving are Sonia Sotomayor, Elena Kagan, Amy Coney Barrett, and Ketanji Brown Jackson.

The justices usually keep a low profile and we hear little about their decisions except for high-profile cases, such as the recent one concerning presidential authority to impose tariffs, where they ruled the president does not.

One of the justices who ruled in the majority, Amy Coney Barrett, recently spoke at a public event in Santa Fe, New Mexico. It was profiled in this article from States Newsroom that I share with you. She explained how judges make decisions, especially ones that don’t make sense to some people. According to Justice Barrett, it’s a matter of “standing up for the law.”

‘You are always going to disappoint one side’: Justice Coney Barrett talks SCOTUS during NM visit

by Julia Goldberg, Oklahoma Voice
March 9, 2026

United States Supreme Court Justice Amy Coney Barrett did not envision a career as a judge. Rather, the former law professor and mother of seven children, was “really more thinking about how to balance a career as a lawyer and being kind of a two-career family and having young children in the house as well,” she said Sunday afternoon during an event in Santa Fe.

Nonetheless, a judge she became, serving on the Seventh Circuit Court of Appeals and then joining the Supreme Court in 2020 after being nominated by President Donald Trump.

Barrett’s appearance — her first trip to the city, she said — came via an event presented by St. John’s College and the University of New Mexico School of Law. The Q&A format, with questions posed by David F. Levi, a former U.S. District Court judge, largely hewed to the outline of Barrett’s book Listening to the Law: Reflections on the Court and Constitution. (affiliate link)

read or listen to sample

Barrett mostly avoided speaking directly to more controversial topics. Tickets were free, but attendees also had the option of purchasing a $20 ticket that included a pre-signed copy of Barrett’s book, which she has been discussing at public events since last year.

Protesters in the dozens, however, showed up to the theater and stayed outside, throughout, loudly denouncing Barrett’s presence in Santa Fe, and her actions on the court, with particular emphasis on her role in overturning federal abortion rights in June of 2022.

Court talk

Barrett wrote her book, she said, to answer common questions she receives about how SCOTUS functions, and to provide the public a better sense of the behind-the-scenes work of deciding law.

“One of the things that I do with the court as a form of civic education is I will speak to groups that come to the court, sometimes schools, sometimes they’re visitors from other countries, and interestingly, across all of those groups, the questions are similar,” she noted.

“How does the court get cases? How do you decide cases? Do the justices get along? I can’t talk to everyone who comes through the court or answer every single letter in detail, but I could write a book that explained the Constitution and the law and the court, and in that way, could invite people in.”

Barrett also insisted that the justices do, in fact, get along.

“Federal judges have life tenure,” she said, “which means as long as you’re in good behavior, you have the job for life, and that’s designed to insulate you from the political process. The president can’t fire you if he doesn’t like a decision that you make, and the same goes for Congress.

The way that I have described it to people is to say it’s kind of like an arranged marriage with no option of divorce. I didn’t pick my colleagues, and my colleagues didn’t pick me; somebody else picked us, and then we’re all kind of thrust upon one another, but we’re all there for the long haul. We’re all there for good. So it serves us best to all get along.” That being said, she added, “I also genuinely like my colleagues.”

Judge Amy Coney Barrett delivers remarks after President Donald J. Trump announced her as his nominee for Associate Justice of the Supreme Court of the United States Saturday, Sept. 26, 2020, in the Rose Garden of the White House. (Official White House Photo by Andrea Hanks)

Being a judge

In response to questions about what qualities best serve a judge, Barrett said over her decade as one, she’d “really grown to appreciate” the need for judges to have “strong character, because I think you need to have a judge that can withstand pressure from the outside.” The “nature of the enterprise,” she said, “is you are always going to disappoint one side. If you can’t steel yourself to following the law where it leads, regardless of whether it earns you enemies, then you’re not a very good judge.”

She described herself as “fortunate to have friends and family who don’t really care about the decisions I make..who love me regardless. But that’s not true of everyone, right?” Being a judge means “you really have to be willing to be lonely, honestly. You have to be prepared to lose friends, and you have to be prepared to be criticized. And I don’t know that I really fully appreciated that before I became a judge.”

Politics on the bench

Barrett has angered people on both sides of the political spectrum. As a Trump appointee, she is generally considered one of the court’s conservative justices.

In addition to voting to overturn Roe v. Wade, which in turn upended access to abortion across the country, she also sided with the court’s conservative majority to expand gun rights and curtail affirmative action.

 On the other hand, she has also voted to limit the president’s authority in some cases, such as siding against the president in the court’s recent tariff case. The New York Times, in an analysis last year, found Barrett to be the Republican-appointed justice “most likely to be in the majority in decisions that reach a liberal outcome.”

When asked about the perception that the court is divided in such partisan ways, Barrett said she found it “extremely frustrating, because none of the nine of us on the court would describe our job as political or describe ourselves as being engaged in the enterprise of delivering partisan results.”

Rather, she said, her “power as a judge is constrained” by Article Three of the Constitution, which established the judicial branch.

“I’m not free to disregard what the Constitution requires, what statutes say, because I might think that it’s unjust,” she said, noting that any number of issues coming before the court might engender strong feelings, such as immigration or the death penalty. “Even friends or family will say, ‘When you get this case, you need to do this. You need to stand up for the little guy,’ or that sort of thing. But I can’t think about my job that way, because what I have to do is stand up for the law.”

Barrett describes herself as an originalist and a textualist, meaning she adheres to the meaning of the Constitution at the time it was written. She also touched on the legal principle of stare decisis, which means abiding by the historical precedents already established in the law.

During her confirmation hearing in 2020, Barrett declined to describe Roe v. Wade as a “super-precedent” case, which she described as “cases that are so well settled that no political actors and no people seriously push for their overruling.” During Sunday’s talk, Barrett did not reference the 1973 Roe v. Wade case specifically, but spoke generally about the doctrine of stare decisis, noting that it means, “that once a case is decided, we generally don’t overrule it, unless a series of factors shows that that precedent has is not only wrong, but is also unworkable.”

‘We’ve all heard her rhetoric before’

The protesters outside the Lensic, whose numbers swelled as the event drew near, appeared disinterested in Barrett’s legal theories. Many were there, they told Source NM, simply because Barrett’s role in overturning abortion rights had caused irreparable harm.

“She’s caused women across, especially the South in the United States, to die because they haven’t had access to abortion,” Lizzie Nutig, a leader from the activist group Dare to Struggle, said. “She’s caused women to stay in abusive relationships…some women experience horrid medical things from having pregnancies that get complicated. We really see her as someone that shouldn’t have a platform to speak. We’ve all heard her rhetoric before. We don’t need to hear it again.”

Janet Williams, president of the Santa Fe Chapter of the National Organization for Women, said she was “angry” at Barrett’s decision overturning Roe v. Wade, and perceived it as a reversal of what Barrett had said during her confirmation hearings. “To me that was a flip flop, and I didn’t like it.”

Dia Winograd, 80, wore a hanger around her neck inscribed with the words, “You can only ban safe abortions.”

“I never thought I’d have to be back out here,” she said.

Joel Aalberts, executive director of the Lensic, told Source NM the protesters were expected and that one of the reasons the Lensic welcomed the event is that “discussion is an essential part of the democracy.”

That being said, in his introduction to the event, Aalberts cautioned audience members that the protests needed to stay outside. Whether out of obedience or friendliness to Barrett, attendees abided.

Learning to disagree

Barrett also insisted, in response to a pre-selected question from a student at one of the sponsor schools, that her Catholic faith does not “color” her work on the court. 

“I don’t take my faith to work in the sense that I, you know, pray about how a decision should be decided, or…call up  the Pope on the phone and say, ‘What are you thinking about this case?’ We live in a country that’s very diverse. The First Amendment grants everybody the freedom to have whatever religion they choose, or no religion at all. And so I see it as antithetical to what my job would be, to try, in any way, to impose my faith on other people, or conceive of my job as part of, you know, a mission of my faith.”

While not speaking directly to her own controversial decisions, let alone the protesters outside the theater’s front door, Barrett did acknowledge the country’s partisan divide, and earned some audience laughter when she herself laughed a bit when asked to explain the optimism about the country she expresses in her book.

“It’s easy to have rose-colored glasses on about times being better before and our being in a uniquely difficult and hostile point in American history,” she said, before going on to cite other difficult times in U.S. history, such as the civil war, and the uprising and political assassinations in the 1960s.

“I think we’ve survived some pretty rancorous times,” Barrett said. “We’ve survived a lot of rifts in our country and the Constitution, we have the oldest living written constitution in the world, and it has survived through all of that. And I choose to treat past as predictive of the future. I think we have a lot of people who love America. I think the 250th anniversary can inspire us, and I think we can build on what prior generations have given us and carry it forward.”

Justice Barrett

This story was originally produced by Source New Mexico, which is part of States Newsroom, a nonprofit news network which includes Oklahoma Voice, and is supported by grants and a coalition of donors as a 501c(3) public charity.

About Santa Fe

Santa Fe is the capital of New Mexico and is known for its arts, nature, and music. It is also the home of Santa Fe National Cemetery, the resting place of thousands of men and women who have served in the United States Armed Forces. I took this photo while visiting the area.

Images in this Post

Images added for illustration and were not affiliated with the original publication.

For Your Thoughts

How do you feel about cases being based on the “law” and historical precedents? When and how should they be overruled?

What other laws seem to be “super-precedent but might be challenged, such as birth-right citizenship? Should they be reconsidered?

What do you think about the “partisan divide” in the United States? Are you as optimistic as Justice Barrett about our future?

Exploring the HEART of Health

I’d love for you to follow this blog. I share information and inspiration to help you transform challenges into opportunities for learning and growth.

Add your name to the subscribe box to be notified of new posts by email. Click the link to read the post and browse other content. It’s that simple. No spam.

I enjoy seeing who is new to Watercress Words. When you subscribe, I will visit your blog or website. Thanks and see you next time.

Use this search box for related posts on this blog or other topics of interest to you.

Dr. Aletha