Can Gastrointestinal Effects Alter Mental Health After Bariatric Surgery?

Although the overall impact of bariatric surgery on mental health is overwhelmingly positive, there remains a subset of individuals in whom mental health issues like self-harm or addictions may appear after surgery. 

Now a paper by Robyn Brown and colleagues, published in Nature Reviews Endocrinology, presents an intriguing hypothesis, that alterations in the gut-axis may play a role in these problems. 

As readers are well aware, bariatric surgery (with some variations depending on the type of procedure) results in profound changes in gut function including alterations in incretin release, intestinal flora, bile acid disposition, and vagal signaling.

As discussed in the paper, all of these factors may potentially affect mental health. However, the evidence is sparse and often contradictory. As the authors point out, despite a strong potential for some of these alterations induced by surgery to alter mental health, few mechanistic studies appear in the animal or clinical literature that could potentially lead to better mechanistic insights and hopefully effective preventive and treatment measures.  

Be the role of the gut in adverse mental health outcomes after bariatric surgery as it may, it’s perhaps important to recall that there are plenty of other probable contributing factors to adverse mental health in bariatric patients. 

These include high rates of pre-existing depression, unmet expectations regarding the life-changing effects of weight loss, post-surgical alterations in the absorption of antidepressant and anxiolytic medications, and changes in alcohol metabolism, which might increase disinhibition and impulsivity, leading to self-harm. 

In addition weight regain and recurrence of weight-related comorbidities, body dissatisfaction (perhaps heightened by excess skin after weight loss), as well as the reduced capacity to eat or enjoy highly-palatable foods as an emotional coping strategy may play a role in individual patients.

Thus, although fear of mental health issues post surgery should probably not deter anyone from undergoing surgery if they really need it, clinicians should be aware of the possibility of adverse mental health outcomes and counsel and monitor patients accordingly. 

Berlin, D