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The Gut Microbiome in First-Episode Psychosis

The Gut Microbiome in First-Episode Psychosis

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This slideshow was originally posted on 6/6/2017.


1. Hooper LV, Wong MH, Thelin A, et al. Molecular analysis of commensal host-microbial relationships in the intestine. Science. 2001;291:881-884.

2. Dinan TG, Borre YE, Cryan JF. Genomics of schizophrenia: time to consider the gut microbiome? Mol Psychiatry. 2014;19:1252-1257.

3. Schwarz E, Maukonen J, Hyytiainen T, et al. Analysis of microbiota in first episode psychosis identifies preliminary associations with symptom severity and treatment response. Schizophr Res. 2017 Apr 22. pii: S0920-9964(17)30204-9. doi: 10.1016/j.schres.2017.04.017. [Epub ahead of print]


The findings and interpretations of this interesting study should more tempered by the researchers and the Psychiatric Times reviewer. Here is the study: https://www.ncbi.nlm.nih.gov/pubmed/28442250

It is not a clinical trial, nor an adequately powered epidemiological study. There were only 28 subjects and only 15 controls. It was not controlled for type of antipsychotic or diet. I did not see info on smoking, drinking, or caffeine intake.

More seriously, the fractionation of the results into an ad hoc search for correlations of numbers of the 7 types of microbiota in these only 28 subjects raises the specter of false-positive p values because the multiple chances of having some of the microbe types attaining difference should mean halving the p value for each test done.

Our zeal to put something into a publication and then make a review (even with some caveats noted) is a type of “review bias” on top of a “publication bias” for what looks like positive results. This type of research should be put in a Journal section titled “pilot studies”, and the authors and reviewers like Dr. Miller here need to be much more humble in their conclusions.

Doug Berger, M.D., Ph.D.
U.S. Board-Certified Psychiatrist
Tokyo, Japan

Douglas @

Interesting and provocative study and issue. A next step would be to analyse the impact of the differing flora and fauna physiologically in the immune system and then as they cross the blood-brain barrier and either contribute or alter inflammation. Understanding the pathways of impact is absolutely necessary to sorting out a causative statement.

Roxanne @

And one more thing. There is a reason that Alzheimers is being referred to as Diabetes Type 3

Audrey @

At this point in time, the microbiome and the significance of imbalances is no longer in question. Cancer research as well as Autism and all kinds of skin diseases have significant findings that our depletion of the soil, fracking and all kinds of changes to the types of food, and the thoughts that we think have generational mal effects on the human body of today. Dr. Pearlmutter and Deepak Chopra, Dr. Mercola have spent years investigating this relationship. The findings are no longer deniable that disruption in the gut causes more havoc than we need. Psychosis, depression, Bipolar D/O- they present the perfect opportunity for practitioners who deal with these mind/body challenges to change the way we look at healing, expand our own way of seeing those who present with these issues. A change as simple as releasing and letting go of sugar from a persons diet and the inclusion of pro and prebiotics as well as Rx antipsychotics and mood stabilizers is a simple, cheap option that is changing peoples lives. We all have thoughts and experiences that could be more joyous and loving, not just those who are labeled

Audrey @

I guess a major factor we don't know however is cause and effect. As stated the gut-brain relationship is bidirectional. It is generally accepted that psychological distress can cause gastrointestinal problems and likely changes to the gut microbiome. An illness as distressing as psychosis (which is both triggered by and significantly adds to psychological stress) is likely to have a significant impact on the gut microbiome. I wonder what the results would look like if controls were those suffering from other forms of mental illness or distress?

Adele @

While I am no doctor, I pose why can't it be that the changes in the gut CAUSE the psychosis and other mental illnesses? If the relationship is bidirectional could that be a cause? Our poor eating habits and processed foods are causing serious illnesses all over our bodies. Currently we treat the symptoms maybe we could be looking more into the CAUSE. Science should seriously consider the brain-gut connection, inflammation, nutrient deficiencies (some caused by medications), acid levels and hormones as potential causes of mental illness. This study gives me hope that science is looking for more answers other than patients are simply mentally ill.

Gail @

I agree with Gail!! MORE RESEARCH must examine the gut to brain correlation!!!

Bea @

Although I can understand where you both are coming from, there have been other studies showing a correlation between the mind and the gut, although not necessarily specific to psychosis, I have read other materials about a correlation between anxiety, depression, stress, and the gut. I do agree with you, however, that much more research need be done before this field is used to apply treatment methods to patients.

Kimberly @

I am very glad to see that someone is asking this question! I have long held the opinion that food and nutrition can have an effect on the mental state. I know of a severely psychotic patient who has been healed without the use of the awful antipsychotics, through the combination of lithium, a careful regimen of brain rebuilding supplements, a strict nutritional clean eating program, and alternative therapies such as sacral/cranial massage therapy and EMDR. Why does the psychiatric community reject these tools in favor of throwing drugs at every condition they encounter?

Laura @

Because as licensed professionals they need to use tools that have been proven to be effective in clinical studies. Good clinical studies are large, time-consuming, complicated, and expensive. The study cited notes that it is a very preliminary study and proves nothing. Sample size needs to be above 1500 for any real statistical use, and having multiple therapies confounds the results. Each item you mention has to be studied separately, and then together, to see what exactly is the item that causes change. And then, the studies need to be replicated by other scientists to ensure the results are real. Good research is difficult. Bad research is easy, which is why people can always find 'stuff' to confirm or deny as they choose.

Richard @

This study reminds me of Dr. Henry Cotton at Trenton State at the turn of the 20th century. His theory was that psychosis was caused by focal infections. His treatment consisted of surgically removing portions of the gastrointestinal tract, teeth or whatever was thought to be causing the condition. His theories and treatments were respected within the psychiatric community, with Trenton State gaining a reputation as being at the forefront in the treatment of mental illness.

While Dr. Cotton claimed high cure rates, his data was found to be inaccurate. In fact, many patients developed infections from the surgery, leading to premature deaths.

The authors of the study are to be commended for their creative thinking.

Lawrence @

Any down side to altering he gut microbiome with probiotics and prebiotics in such patients, while awaiting larger RCT studies?
William O'Neill, MD

William @

The following comment is on behalf of the author:

Dr. O’Neill raises an interesting and important question. While presently the evidence does not support widespread use of probiotics in patients with psychosis, these agents are considered to be relatively safe.

Outside of psychosis, studies using probiotics have reported abdominal cramping, nausea, fever, soft stools, flatulence, and taste disturbances as adverse effects. Of note, the FDA has issued a warning that advises practitioners of the potential risks of using dietary supplements containing live bacteria or yeast in immunocompromised patients.

Readers are also referred to two previous RCTs of adjunctive probiotics in schizophrenia:

Probiotic normalization of Candida albicans in schizophrenia: A randomized, placebo-controlled, longitudinal pilot study.
Severance EG, Gressitt KL, Stallings CR, Katsafanas E, Schweinfurth LA, Savage CLG, Adamos MB, Sweeney KM, Origoni AE, Khushalani S, Dickerson FB, Yolken RH.
Brain Behav Immun. 2017 May;62:41-45.

Effect of probiotic supplementation on schizophrenia symptoms and association with gastrointestinal functioning: a randomized, placebo-controlled trial.
Dickerson FB, Stallings C, Origoni A, Katsafanas E, Savage CL, Schweinfurth LA, Goga J, Khushalani S, Yolken RH.
Prim Care Companion CNS Disord. 2014;16(1). pii: PCC.13m01579.

Brian Miller, MD, PhD, MPH
Associate Professor
Augusta University
Department of Psychiatry and Health Behavior
Augusta, Georgia
Schizophrenia Section Editor for Psychiatric Times

PsychTimes @

Those pre and probiotics aline cannot correct the gut esp. if the gut is really bad. Thus, a nutritional diet based on leafy greens and protein are best suited for defeating candida overgrowth! The diet would last months to two years depending on severity.

Bea @

Hi...can You tell me , please, can essetial oils (oregano oil) help defeating Candida overgrowth?
Thank You

branka @

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