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Major Depressive Disorder

Major Depressive Disorder

Major Depressive Disorder (MDD) is very common in the United States and worldwide. In fact, studies have demonstrated that about approximately 12% of men and 25% of women will experience a MDD episode in their lifetime so severe that it impairs their ability to function. At any given time, it is estimated that about 5-6%, or one in twenty persons, is suffering from MDD. That translates into 18 million Americans suffering from MDD at any given time. The financial burden to society of MDD (lost productivity, cost of treatment) is staggering: it is estimated that MDD costs approximately $40 billion dollars per year in the United States. Severe MDD is costly in loss of life: it is estimated that 12-15% of individuals suffering from severe MDD commit suicide. A recent report from the United States Surgeon General (LINK) concludes that lack of access to proper diagnoses and treatment for MDD is currently a major U.S. health crises.

Symptoms of MDD

The common cardinal symptoms of depression include: persistently depressed or sad mood lasting 2 or more weeks, profoundly decreased energy (“dragging through the day”), persistent feelings of hopelessness, disrupted sleep (typically difficulty falling asleep and staying asleep, but also excessive sleep), difficulty concentrating, change in appetite (typically loss of appetite, but can also be increased appetite) often accompanied by weight loss/gain, persistently impaired self-esteem (feeling “worthless”), decreased interest in activities previously giving the person pleasure, and thoughts of suicide. Other commonly reported symptoms include crying spells, isolativeness, lack of motivation, increased perception of pain, increased anxiety and irritability, and difficulty making simple decisions.

Other features of depression:

  • MDD tends to recur: if you have experienced one episode of you are much more likely to experience a second. For this reason, those with a previous history of depression need to be mindful of this tendency for depression to recur.

  • MDD is often genetically based. Having a first degree relative (brother, sister, mother, father, child) places a person at much higher risk for experiencing depression. Often, determining what treatment worked for a relative can direct effective antidepressant treatment.

  • studies indicate that MDD profoundly negatively impacts many medical conditions including: cardiovascular disease (heart disease and stroke), cancers, autoimmune diseases, pain conditions, and diabetes among others. Studies demonstrate that having depression can actually increase a person’s likelihood of dying from a heart attack. MDD has a close association with stroke.

  • MDD is frequently complicated by other psychiatric and psychological conditions, such as substance addiction (particularly alcohol and pain killers), personality disorders, and anxiety disorders.

  • studies suggest that MDD, especially prolonged severe depression, may actually lead to damage to a persons brain.

What causes a person to develop MDD?

We don’t currently fully understand why some individuals develop this condition, while others do not. Current studies of MDD suggest that early life experiences combined with a genetic predisposition, place a person at risk for developing MDD. Through brain imaging studies we understand that depression affects certain critical regions of the brain responsible for basic biological drives (e.g., sleep, appetite, sexual desire, stress response). We also know that certain brain chemicals, referred to as neurotransmitters (serotonin, norepinephrine, dopamine among others) are critically involved in depression.

Don't Give Up

There is reason to be optimistic: we are making steady advances in understanding the nature of MDD and treatment options are growing.