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Depression and Illness

Co-Occurrence of Depression with Other Illnesses

Depression can coexist with other illnesses. In such cases, it is important that the depression and each co-occurring illness be appropriately diagnosed and treated.

Research has shown that anxiety disorders­which include post traumatic stress disorder (PTSD), obsessive compulsive disorder, panic disorder, social phobia, and generalized anxiety disorder­commonly accompany depression. Depression is especially prevalent among people with PTSD, a debilitating condition that can develop after exposure to a terrifying event or ordeal in which grave physical harm occurred or was threatened. Traumatic events that can trigger PTSD include violent personal assaults such as rape or mugging, natural disasters, accidents, terrorism, and military combat.

PTSD symptoms include: re-experiencing the traumatic event in the form of flashback episodes, memories, or nightmares; emotional numbness; sleep disturbances; irritability; outbursts of anger; intense guilt; and avoidance of any reminders or thoughts of the ordeal. In one NIMH supported study, more than 40 percent of people with PTSD also had depression when evaluated at one month and four months following the traumatic event.

Substance use disorders (abuse or dependence) also frequently co-occur with depressive disorders. Research has revealed that people with alcoholism are almost twice as likely as those without alcoholism to also suffer from major depression. In addition, more than half of people with bipolar disorder type I (with severe mania) have a co occurring substance use disorder.

Depression has been found to occur at a higher rate among people who have other serious medical illnesses such as heart disease, stroke, cancer, HIV, diabetes, and Parkinson’s. Symptoms of depression are sometimes mistaken for inevitable accompaniments to these other illnesses. However, research has shown that the co-occurring depression can and should be treated, and that in many cases treating the depression can also improve the outcome of the other illness.

Depression may seem to be inevitable when you have a serious medical problem. After being diagnosed with a serious heart problem, or cancer, or any life threatening disease, you may believe that it is reasonable to also become depressed. However, this does not mean that your depression should be ignored. When you are depressed, you are less likely to follow through with the necessary treatment to combat your medical problems, and that reduces your chances of successfully beating a life threatening disease. Serious depression also inhibits your immune system, and that also affects your treatment outcome. If you have a serious medical condition, and you are depressed, remember that treating your depression will also help to treat your medical condition.

Men: Depression and Bipolar Disorder: