Mental Health and inflammation
Is there a link?
It is estimated that 1 in 4 people in the United Kingdom will experience a mental health problem each year. Mixed anxiety and depression is the most common of these, with almost 8% of people meeting the criteria for a formal diagnosis. Many mental health problems originate from adverse childhood experiences or during early adult life, meaning that three-quarters of problems are established by the age of just 24. Mental illness is not just a problem seen in younger age groups, approximately 15% of adults aged 60 and over also suffer from a mental health issue.1
Raised inflammatory markers are persistently seen in people with conditions such as cardiovascular disease, diabetes, autoimmune disorders and cancer. There appears to be a strong correlation between these chronic illnesses and depressive disorders. Around 1 in 5 people with cardiovascular disease experience a major depressive disorder. A diabetes diagnosis doubles the odds of having depression and up to 70% of patients with autoimmune diseases, such as rheumatoid arthritis or systemic lupus erythematosus, experience depression2.
Research is increasingly showing that there could be a link between mental health and inflammation and I am interested in finding out why.
What is Inflammation?
During an inflammatory episode the body releases cytokines, which are small, cell-signalling protein molecules. These inflammatory markers launch signalling cascades that incite the immune system into action. Cytokines also induce acute phase proteins, such as C-reactive protein (CRP), which can activate the immune system. Once inflammation is active, it is often self-perpetuating. These inflammatory cytokines travel throughout the body causing oxidative stress to the tissues and mitochondria, specifically, in the brain. Inflammation serves to alter the effects of amino acids such as tryptophan towards production of anxiety-provoking chemicals like quinolinate, instead of toward serotonin and melatonin, hormones that regulate human functions such as sleep, appetite and mood. These by-products often produce a replicable collection of symptoms called “sickness syndrome”, noted for its overlap with “depressive” symptoms which include lethargy, sleep disturbance, decreased social activity, mobility, libido, learning, anorexia, and anhedonia.
Our immune system secretes antibodies that are distributed in our blood to help fight infection or repair a problem. The blood-brain barrier is supposed to protect your brain from those antibodies. But for reasons that aren’t yet known, when inflammation reaches the brain, the cytokines wreak havoc on our neurotransmitters, interfering with brain function. When the blood-brain barrier is penetrated, the immune system mistakenly attacks the body, which can lead to symptoms such as anxiety, depression, and hallucinations. Studies have consistently found higher levels of inflammation in mentally ill patients with suicidal thoughts, PTSD, and chronic fatigue.3Psychiatric research has also reported that patients with higher levels of inflammatory markers, such as CRP, are less likely to respond to antidepressants, and more likely to respond to anti-inflammatories.4
A psychiatrist’s view?
Interestingly I have found a book, written by Professor Edward Bullmore from the University of Cambridge called “The Inflamed Mind”.
“Worldwide, depression will be the single biggest cause of disability in the next twenty years. But treatment for it has not changed much in the last three decades. In the world of psychiatry, time has apparently stood still...until now with Edward Bullmore's The Inflamed Mind: A Radical New Approach to Depression”.5
Click the below video to watch more:
In an ever changing digital world, could the association between inflammation and mental health be a starting point for a change in how insurance underwriters assess mental illnesses? Approximately 78% of adults own a smart phone, and many others of us own smart watches or step trackers. Some physical clinical symptoms of depression include changes in weight, lack of energy and disturbed sleep. Social indicators include missing work, avoiding contact with friends and reclusive behaviour. All of these devices have the capacity to collect specific data, such as the number of steps taken or climbed per day, hours slept and daily exercising minutes. Being able to access information that shows physical activity or capacity could potentially provide a view on an individual’s mental state at any stage of their lives and could become an important underwriting consideration for the future. After all, “the body cannot live without the mind”.
Munich Re’s psychiatrist Dr Daniela Krause, states that “the hypothesis that inflammation may be associated with depression is also supported by positive results from randomised trials of anti-inflammatory agents in depressed patients”.