Treatment of Comorbid Depression in Medical Illness

Abstract

An increasing body of evidence demonstrates a bidirectional relationship between depression and medical illness with each negatively affecting the outcome and treatment of the other. Comorbid depression in the medically ill is associated with increased functional impairment, decreased quality of life, and increased medical costs. Depressed patients have also been shown to have more medically unexplained symptoms as well as a decreased satisfaction in the treatment of these conditions compared to nondepressed patients. Additionally, depression is linked to unhealthy behaviors, such as smoking, sedentary lifestyle, and overeating, which also increase the risk of medical illness and further impact the underlying medical condition. Epidemiological studies report an increased prevalence rate of depression in patients with a medical condition compared to the general population. No longer considered an ‘‘appropriate risk’’ of having an illness, researchers have begun examining the direct impact of depression on a variety of medical illnesses, such as coronary artery disease, stroke, diabetes, cancer, HIV/AIDS, and neurological disorders. These studies show an increased disability and mortality associated with depression, generating further questions about appropriate treatment to reduce these risks. Available evidence demonstrates the benefit of antidepressants in the treatment of depression co-occurring with a variety of medical illnesses. The selective serotonin reuptake inhibitors (SSRIs) and newer antidepressants are considered the first-line agents because of their proven safety and tolerability, especially in these medically tenuous patients. Additionally, studies show that treatment of depression produces a significant reduction in symptoms, annual disability scores, and number of disability days lost per year among high users of health services. Antidepressants are theorized to produce their effects through a variety of different ways from improvements in mood and self-care to effects on the hypothalamus-pituitary-adrenal (HPA) axis and the body’s stress response. The table below compiles literature reporting on the use of antidepressants for the treatment of depression in a variety of comorbid medical illnesses. The recommendations made in this table are based upon available evidence. First-line agents are those medications that have the most convincing evidence supporting use in a particular disease state. Therefore these first-line antidepressants may be a good initial medication choice.