A tale of two comorbidities: Understanding the neurobiology of depression and pain

The comorbidity of chronic pain and depression has been consistently associated with a poor prognosis and greater disability in patients as compared to those suffering from each illness alone. This further has implications on significant financial costs to the patients and to our society. The biological underpinnings of major depression and chronic pain have considerable overlap in the areas of genetic, structural, functional, neuroendocrine and neurotransmitter functionality. Although the field has evolved in the past decade, more efforts should now focus on understanding the biological underpinnings of this shared comorbidity, while shedding light on treatment implications for these two devastating conditions.