A new blood test promises early detection of anxiety disorders, a strike against the old regime of simply interviewing patients, observing their behavior and making a diagnosis. The research team was led by Alexander Niculescu, professor of psychiatry at Indiana University, who has already developed similar tests for mood disorders and post-traumatic stress disorder.

The new “BioM-95” test relies on 95 genetic markers identified during an elaborate study that examined both patients and their body’s RNA, which stress and mental illness can modify. The promise of a swift blood test is great: a 2005 study laid bare one of the great shortfalls in psychiatry, that it often takes several years for someone suffering a mental illness to receive treatment. In the case of anxiety disorders, the study found an especially long lag of 9 to 23 years.

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Going by Genes

Researchers had already discovered many of the genetic markers in the test. But it wasn’t until Niculescu tested their predictive power as a whole that he found an important new one, ERCC6L2, that is common in anxious patients with depression. The gene has something to do with DNA repair and the functioning of mitochondria, the energy powerhouses inside cells.

“Reactivity and repair may be key functions of anxiety,” the study says.

More importantly, Niculescu pitted the genetic approach against the traditional “structured interview” method of somehow questioning and rating a patient on the severity of their disorder. With real patients, BioM-95 proved better at predicting future hospitalizations.

“The current approach is to talk to people about how they feel to see if they could be on medications,” Niculescu says in a press release, “but some medications can be addictive and create more problems.”

Neglected Medications

The study found only minor genetic support for the use of benzodiazepine sedatives such as Xanax and Valium, which can cause psychological dependence and a dangerous withdrawal syndrome. To search for alternative therapies, the study matched the genetic markers to medications that also modified them and came up with a long list of recommended drugs, many of them unconventional. Topping the list is valproate, an old bipolar drug that increases the GABA neurotransmitter in the brain, which can have a tranquilizing effect.

Next is the powerful antipsychotic medication clozapine, used sparingly by doctors because it can affect white blood cells in the body, among other things. More palatable treatments such as omega-3 fatty acids, meditation and Prozac also ranked highly, along with lithium, which reduces the risk of suicide.

Even more unusual drugs showed genetic promise, such as thalidomide (long banned), female sex hormone, a local anesthetic compound, the muscarinic substance atropine, a plant toxin, a heart drug and loperamide, the gut-slowing anti-diarrhea medication found in Imodium. Loperamide works by binding to opioid receptors in the peripheral nervous system and can cause constipation with long-term use.

In contrast, Stahl’s Essential Psychopharmacology, a standby in psychiatry, lists primarily antidepressants and benzodiazepines as the go-to treatments for anxiety disorders and makes no mention of valproate or lithium.

Niculescu’s Indianapolis-based startup, MindX Sciences, is already offering blood tests for mood and anxiety disorders, pain, PTSD, suicide risk and memory, but patients must pay out of pocket. The company says it will pursue “Medicare and insurance coverage in the near future.”