Depression: Is it More Than Just a Disorder of the Mind?

Western medicine separates physical and mental health into two categories; and these categories do not overlap. For example, if you have cancer and a mental disorder, the common thinking is that the physical disease must be treated separately from the mental one – but it may be time to reexamine that notion. New evidence shows a strong correlation between inflammatory diseases and major depressive disorder. However, the diagnostic criteria mental health professionals follow to form diagnoses, the DSM-5, specifically states that major depression cannot be diagnosed in a patient who has a major inflammatory disorder. In fact, most physicians would simply deduce that a person with a painful major inflammatory disorder such as rheumatoid arthritis has good reason to be depressed.

Inflammatory Disease and Major Depression

Of course, no one denies the obvious fact: It’s miserable to be in chronic pain. Yet statistics and even brain scans show it’s not a coincidence to be afflicted with comorbid inflammatory disease and major depression. Epidemiological data shows that while 10% of the general population has some form of clinical depression, 25% of patients with rheumatoid arthritis, inflammatory bowel disease, psoriasis, chronic lung disease, and other inflammatory or autoimmune disorders suffer from depression. On the flipside, about one-third of patients with depression have low-grade inflammation. This scientific revelation could change the way we treat depression today, especially in patients with inflammatory diseases.

Even experiencing a transient inflammatory state, such as fighting the common cold or flu can cause symptoms commonly associated with depression, including troubled sleep, fatigue, foggy thinking, and impaired concentration. Of course, major depression is not an inflammatory disease, or every diagnosed patient would improve with anti-inflammatory medication.

So, what is the scientific link?

Neuroimmunology, a newer scientific field, posits that the immune system’s inflammatory response changes the way the brain works and causes behavioral changes. This means inflammation not only causes a body temperature increase, but depressive symptoms as well. Scientists say the behavior is not caused directly by the illness itself, but the body’s immune response to it. In fact, research going back 30 years has demonstrated that levels of inflammatory proteins are significantly higher in depressed patients as compared to healthy control patients. Furthermore, research has shown that inflammation often can predict depression. However, it will likely take many more years to change the mindset that depression is a mental disorder only, with no physical component.

Posted in

Dr. Tina A. Watson

Leave a Comment