A number of inflammatory conditions coincide with mood disorders. Women with chronic health issues who pursue diagnosis are commonly labeled as having anxiety and the physical symptoms as a result of that. However, there is a significant body of evidence pointing to mood disorders as being organic symptoms of the inflammation rather than the psychological reaction to the changes that come with chronic illness. What we often frame as behavioral or psychiatric symptoms are perceived by some researchers as “sickness behavior” that promotes healing. Low energy, appetite and mood, along with sleeping more, redirect energy from less important functions to immune defense or wound repair.
Patients with autoimmune disease, diabetes, metabolic syndrome, asthma and allergies all experience mood disorders. Psoriasis dramatically increases the frequency of depressive symptoms. Cardiovascular disease patients are more likely to have major depressive disorder or bipolar disorder than the general population. Major depressive disorder increases risk of coronary artery and poorer prognosis with cardiovascular disease.
In one study with ISM and CM patients, 75% reported symptoms of depression. In a different study, 60% reported depressive symptoms and anxiety. Asthma and wheezing are independently associated with major depressive episodes in a massive study with almost 250,000 people from 57 countries.
Depression patients who have attempted suicide show increased TNF and IL-6, along with low IL-2, compared to depression patients who have not attempted suicide. Elevated CRP is also associated with depression. Alexithymia, in which the patient feels no emotions, affects 39-46% of patients with major depressive disorder. These patients also demonstrate very high CRP levels which can decrease cognitive functions.
Treatment of chronic illnesses can also improve associated mood disorders. Aspirin is currently being trialed as a treatment for bipolar disorder. Use of aspirin with an SSRI produced better response than just the SSRI. Use of COX-2 inhibitors like celecoxib with antidepressants improves symptoms and decreases levels of IL-6 and IL-1b. NSAIDs, which also interfere with COX-2, reduce depression when compared to placebo.
Omega-3 polyunsaturated fatty acids have been found to be potent antidepressants. These molecules also decrease the production of prostaglandins and cytokines. Omega-3 polyunsaturated fatty acids interfere with the COX-2 enzyme that produces prostaglandins. Curcumin also decreases cytokine production, as well as normalizing activity from the HPA axis and improving mood.
References:
Furtado M, Katzman MA. Examining the role of neuroinflammation in major depression. Psychiatry Research 2015: 229, 27-36.
Rosenblat JD, et al. Inflamed moods: a review of the interactions between inflammation and mood disorders. Progress in Neuro-Psychopharmacology & Biological Psychiatry 2014; 53, 23-34.