From the article:
The authors found that in addition to being linked to numerous physical health issues, including cancer and diabetes, systemic inflammation is linked to mental health issues such as depression. Among patients suffering from clinical depression, concentrations of two inflammatory markers, CRP and IL-6, were elevated by up to 50 percent.
Fagundes said chronic inflammation is most common in individuals who have experienced stress in their lives, including lower socio-economic status or those who experienced abuse or neglect as children. Other contributing factors are a high-fat diet and high body mass index.
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The study also found that depression caused by chronic inflammation is resistant to traditional therapy methods, but can be treated with activities such as yoga, meditation NSAIDS and exercise.