Depression is a mental health disorder that is classified as an Axis I disorder in the Diagnostic and Statistical Manual of Mental Disorders. Depression is further classified as a mood disorder and fits into the same diagnostic category as bipolar disorders and anxiety disorders.
Basics
The Diagnostic and Statistical Manual of Mental Disorders provides criteria for doctors to look for when assessing a person for depression, but there is not a specific test to determine if a person has or does not have depression. A doctor will determine if the person's behaviors and moods meet the specific diagnostic criteria of depression.
Types
When a doctor is determining if depression is present in a person, she will determine what type of depression is present by ruling out the other forms. Generally, the forms of depression a doctor will assess for include major depression, dysthymia, seasonal affective disorder and bipolar disorder.
Specifics
A doctor will talk with the patient and determine how long the symptoms have been present and what types of symptoms are present. To receive a diagnosis of major depression, a person must possess at least five symptoms for two weeks in a row and the symptoms must significantly interfere in the individual's life, notes the Anxiety Disorder Association of America, or ADAA. A diagnosis of dysthymia requires the person to possess some of the same symptoms as major depression, but in a less severe, more chronic form; the symptoms must be present for at least two consecutive years. For bipolar disorder to be diagnosed, the person must possess the symptoms of depression and also have experienced an episode of mania or hypomania. The specific diagnosis of seasonal affective disorder requires that depression symptoms are present in low-light months, such as the winter, and lift during the spring and summer months when there is lots of sunlight.
Symptoms
The experience of depression symptoms varies from individual to individual and a doctor will have to be aware of these potential variations when making a diagnosis. According to the National Institute on Mental Health, or NIMH, the symptoms of depression include lack of pleasure, fatigue, feelings of guilt, feelings of hopelessness, irritability, inability to concentrate, eating more or less, sleeping more or less, thoughts of suicide, constant sadness and aches and pains unrelated to any other medical condition.
Considerations
Doctors should rule out the presence of other mental health disorders or medical conditions when testing for depression. The NIMH reports that some viruses or a thyroid disorder can cause a person to experience symptoms of depression, but these conditions can be treated and remedied with a medical intervention. Therefore, a doctor should run specific medical tests to rule out these conditions.
Also, other mental health conditions may exist at the same time as the depression and doctors should assess for these disorders. Possible co-existing disorders include anxiety disorders, substance abuse or dependence and personality disorders. Any of these common co-occurring disorders that are found to be present at the same time as depression will need to be treated in addition to the depression.
