We talk to Professor Edward Bulmmore - the author of the ground-breaking book The Inflamed Mind - about how inflammation causes depression.
In this ground-breaking book, Cambridge University’s Professor Edward Bullmore illuminates a little-known history, identifies where we have gone wrong, and plots the pathway
towards a potential new treatment for one of western medicine’s most intractable problems – depression. Indeed, future generations might well look back upon his insights as the catalyst for a paradigm shift in the treatment of depression. And don’t we need it?
Depression, for millions of people, continues to be a maddeningly slippery issue to understand and treat. For Professor Bullmore, interest in its treatment goes back to the early 1980s when “at that time the dominant idea was that depression was caused by an imbalance of neurotransmitters in the brain: not enough serotonin, for example. To this day, more than 30 years later, many patients are treated for depression with SSRIs – the serotonin reuptake inhibitors exemplified by Prozac – on the grounds that these and related drugs work as anti-depressants because they boost levels of serotonin in the brain”.
“It became clear…”, he explains, “…(in) around 2010, that we needed to think differently about how to treat depression because the old model of boosting serotonin (or noradrenaline or dopamine) as a panacea for all patients with depression was not delivering for more effective new drugs, and therapeutic progress in real-life had stalled.”
Western medicine, using a modality of thinking that goes all the way back to the ‘mind-body dualism’ of the 17th century French philosopher Descartes, has succeeding “in treating physical disease as if it was a biological machine gone wrong…..with an intense medical focus on physical mechanism….comes at the cost of disregarding any mental aspects of the patient – like their personality, their sense of humour, their sexual orientation – which doctors can’t explain in terms of genes, cells, molecules and the other components of the body machine.” In other words, contrary to Descartes’ dualistic conception, mind and body are intimately connected, not universes unto themselves; and the bridge is the ‘blood-brain barrier’. Mind affects body; and body, specifically, inflammation, can and does affect the mind.
This promising new way of approaching the treatment of depression might well represent a paradigm shift. And if “the most powerful lever of change in the history of medicine was always the advent of a new treatment” then what might this new treatment be?
“If we had a new drug for depression…” Professor Bullmore explains, “…that worked well for some of the many patients, about a third, who don’t recover entirely after treatment with SSRIs or psychotherapy, that would be a big step forward. If we had a blood test or a biomarker that we could use to predict which patients with MDD (major depression disorder) were particularly likely to respond well to this new drug that would be epochal”.
“One of the things I like about the new science of neuro-immunology”, he continues, “is the growing evidence it provides that social and psychological stress has inflammatory effects. For example, children who have experienced abuse or adversity in childhood are more likely to be inflamed (and depressed) as adults. If you think about the threat to survival that is represented by extreme childhood stress, like early maternal separation, it is perhaps not surprising to realize that the immune system will respond as it responds to other childhood survival threats like trauma or infection. So at this stage, I don’t see a hard line between
psychological factors like stress and physical mechanisms like inflammation. I think in future we may understand more about how stress causes inflammation and how stress-busting psychological or social interventions could have anti-inflammatory effects.”
Like many inventions or medical breakthroughs, in retrospect, it seems obvious. But what has changed over the last four decades to lead to a clearer vision of a way forward? Professor Bullmore explains that “immunology has become enormously more complex, detailed and powerful than it was when I first encountered it in the 1980s. The immune system has turned out to be ubiquitous in the body and brain and inflammation has been directly implicated in far more diseases than were considered to be inflammatory 20 or 30 years ago. Many of the most exciting recent or predicted new drugs for disorders ranging from multiple sclerosis to cancer to coronary heart disease work by acting on the immune system. Immunology is fast becoming the central science of medicine and therapeutic innovation; whereas when I was a medical student in the 1980s it seemed like a bit of a backwater.”
Overturning what had been accepted for years by the medical profession that mind and body were separated by a ‘blood-brain’ barrier, the interconnection between the immune system and the brain now seems wide ranging. Professor Bullmore, using the quickly evolving science of immunology and the courage of his conviction, has shown that inflammation can trigger your immune system to produce antibodies which travel to the brain. In so doing, he has shined a light on a pathway that might very well lead to solving one of medicine’s great puzzles: the cause and therefore the possible treatment of depression.
J.A. Gleeson is a Personal Trainer. The author welcomes any feedback about his articles and book reviews. He can be reached at firstname.lastname@example.org