History and physical examination: To diagnosis depression the doctor must first rule out all other disease possibilities. Typically, the diagnosis begins with a medical history, including questions about the duration, severity, and characteristics of symptoms. The physician will ask about diet, stress, any medications currently being taken, and changes in sleep patterns. Questionnaires may be used to determine the level of depression.
Diagnosis also involves ruling out other mental health conditions that may produce symptoms similar to depression. These may include other mood disorders, such as bipolar, schizophrenia, attention-deficit/hyperactivity disorder (ADHD), and borderline personality disorder.
A diagnosis of depressive disorder is based on criteria found in the Diagnostic and Statistical Manual of Mental Disorders-IV-TR (DSM-IV-TR) developed by the American Psychiatric Association.
Laboratory tests: Blood tests can determine if the levels of neurochemicals (brain chemicals), including serotonin, dopamine, and norepinephrine, are healthy. Tests may be ordered to rule out other causes, such as blood or urine tests to determine the balance of salts and sugar in the blood, hormone function, blood cell counts, and drug and alcohol levels. Computerized tomography (CT) scan, positron emission tomography (PET), or magnetic resonance imaging (MRI) of the head may be ordered to check for blood clots, bleeding, or tumors. A spinal tap (lumbar puncture) may be ordered to get a sample of spinal fluid to determine if a brain infection, such as meningitis or encephalitis (both forms of brain inflammation), exists. These tests may rule out other conditions that may be present (such as brain tumor or other disease), and may determine if imbalances in neurochemistry are present.
signs and symptoms
The onset of the first episode of depression may not be obvious if it is gradual or mild. The symptoms of depression represent a significant change from how a person functioned before the illness. Symptoms of depression can either be mild, moderate or severe.
Loss of interest in normal daily activities: An individual may lose interest in or pleasure from activities that they used to enjoy.
Depressed mood: The individual may feel sad, helpless or hopeless, and may have crying spells.
Sleep disturbances: Sleeping too much or having problems sleeping can be a sign of depression. Waking in the middle of the night or early in the morning and not being able to get back to sleep are typical.
Impaired thinking or concentration: The individual may have trouble concentrating, making decisions, or have problems with memory.
Weight changes: An increased or reduced appetite and unexplained weight gain or loss may indicate depression.
Agitation: The individual may seem restless, agitated, irritable, and easily annoyed.
Fatigue (tiredness): Weariness and a lack of energy nearly every day are common signs of depression. The individual may feel as tired in the morning as they did when going to bed the night before.
Low self-esteem: Feelings of worthlessness and excessive guilt are common symptoms of depression.
Loss of sexual interests: If the individual was sexually active before developing depression, they may notice a dramatic decrease in the level of interest in having sexual relations.
Preoccupation with death: The individual may have a persistent negative view of their situation in life and the future. They may have thoughts of death, dying or suicide.
Other physical symptoms: Depression can also cause a wide variety of physical complaints, such as gastrointestinal problems (indigestion, constipation, or diarrhea), headache, and backache. Many people with depression also have symptoms of anxiety, including restlessness, inability to concentrate, and loss of sleep.
Depression in children and the elderly: Children, teens, and older adults may react differently to depression. In these groups, symptoms may take different forms or may be masked by other conditions. Kids may pretend to be sick, worry that a parent is going to die, perform poorly in school, refuse to go to school, or exhibit behavioral problems. The elderly may be more willing to discuss the physical symptoms of depression, instead of their emotional difficulties, including constant complaining about aches and pains.
Suicidal thoughts: Suicidal thoughts may accompany depression. Anyone who has suicidal feelings, talks about suicide, or attempts suicide should be taken seriously and should receive immediate help from a mental health specialist. Certain warning signs may indicate serious depression and the possibility of suicide. Danger signs include pacing, agitated behavior, frequent mood changes and sleeplessness for several nights, actions or threats of assault, physical harm or violence, threats or talk of death or suicide, such as "I don't care anymore," or "You won't need to worry about me much longer," withdrawal from activities and relationships, putting affairs in order, such as saying goodbye to friends, giving away prized possessions or writing a will, a sudden brightening of mood after a period of being depressed, or unusually risky behavior, such as buying or handling a gun or driving recklessly can be indicators of suicidal thinking.
risk factors and causes
Neurotransmitter imbalances: Studies suggest that a low or high level of neurotransmitters such as serotonin, norepinephrine, or dopamine cause depression. Studies have found evidence that a change in the sensitivity of the receptors on nerve cells to these neurotransmitters may be one issue, along with an imbalance in the amounts of neurotransmitters. Balancing neurotransmitters with drug therapy is the current focus for treatment of major depression.
Heredity: Researchers have identified several genes that may be involved in bipolar disorder and are looking for genes linked to other types of depression. But not everyone with a family history of depression develops the disorder, and conversely, people with no family history of the disorder can become depressed.
Gender: Depression occurs twice as frequently in women as in men, for reasons that are not fully understood. Hormonal changes such as menstrual cycle changes, postpartum period, pre-menopause, pregnancy, childbirth, miscarriage, and menopause are the most likely causes of depression.
Although men are less likely to suffer from depression than women, six million men in the United States are affected by the illness. Men are less likely to admit to depression. The rate of suicide in men is four times that of women, though more women attempt it.
Stress: Stressful life events, particularly a loss or threatened loss of a loved one or a job, can trigger depression.
Medications: Long-term use of certain medications, such as some drugs used to control high blood pressure, sleeping pills, or birth control pills, may cause symptoms of depression in some people.
Illnesses: Having a chronic illness, such as heart disease, stroke, diabetes, cancer or Alzheimer's disease, puts an individual at a higher risk of developing depression. Having an underactive thyroid (hypothyroidism), even mildly, also can cause depression. Physical trauma (damage) to the brain can also trigger depression.
Personality: Certain personality traits, such as having low self-esteem and being overly dependent, self-critical, pessimistic and easily overwhelmed by stress, can make an individual more vulnerable to depression.
Postpartum depression: It is common for mothers to feel a mild form of distress that usually occurs a few days to weeks after giving birth. During this time the woman may have feelings of sadness, anger, anxiety, irritability and incompetence. A more severe form of the baby blues, called postpartum depression, also can affect new mothers.
Hormones: Women experience depression about twice as much as men, which leads researchers to believe hormonal factors may play a role in the development of depression.
Alcohol, smoking, and drug abuse: Abuse of alcohol, cigarettes, and recreational drugs such as cocaine, methamphetamine (crystal meth), ecstasy, and marijuana can lead to depression.
Previous depression: More than half of those who experience a single episode of depression will continue to have episodes that occur as frequently as once or even twice a year. Without treatment, the frequency of depressive illness as well as the severity of symptoms tends to increase over time. Left untreated, depression can lead to suicide.
About half of the people who have a first episode of depression will have another episode within 10 years. The risk of further bouts of depression is higher than in someone who has never been depressed.
Alcohol and drug abuse are very common among people with depression.
Depressive disorder can have devastating effects on relationships as complete isolation and withdrawal during depression are common.
Suicide may be a complication of untreated, mistreated, or misdiagnosed depression. Women attempt suicide more often than men do, but men are much more likely to succeed in killing themselves. The rate of suicide is four times greater for men. Men over 70 are the most likely to commit suicide.
Calling a local suicide hotline, such as the National Suicide Prevention Lifeline at 1-800-273-8255, can be help for someone thinking of suicide.