Depression is different from the usual mood fluctuations and short-lived emotional responses to everyday life stressors. When it is recurrent with moderate or severe intensity, depression can become a serious health condition that causes the affected person to suffer greatly and function poorly at work and school and can affect relationships with family and friends. At its worst, depression can lead to suicide. Over 700,000 people die every year due to suicide. Barriers to effective care for depression include a lack of resources, lack of trained health care providers, and social stigma associated with mental health disorders.^[1] See Figure 7.5^[2] for an artistic depiction of an individual experiencing depression.

During a depressive episode, the person experiences a depressed mood (feeling sad, irritable, empty) or a loss of pleasure or interest in activities (anhedonia) for most of the day, nearly every day, for at least two weeks. Several other symptoms may also be present, which may include poor concentration, feelings of excessive guilt or low self-worth, hopelessness about the future, thoughts about dying or suicide, disrupted sleep, changes in appetite or weight, and feeling especially tired or low in energy. In some cultural contexts, some people may express their mood changes more readily in the form of bodily symptoms (such as pain, fatigue, or weakness) that are not due to another medical condition. During a depressive episode, the person experiences significant difficulty and/or impairment in important areas of personal, family, social, educational, and work functioning.^[3]

A depressive episode is categorized by a provider as mild, moderate, or severe depending on the number and severity of symptoms, as well as the impact on the individual’s functioning.^[4] Mild severity indicates the symptoms to make the diagnosis are present but result in minor impairment in social or occupational functioning. Moderate severity indicates symptoms and impairment are between mild and severe. Severe indicates the intensity is seriously distressing, unmanageable, and markedly interferes with social and occupational functioning. Read the full list of criteria for Major Depressive Disorder from the DSM-5 in the following box.

Seasonal Affective Disorder

Seasonal affective disorder (SAD) is a type of major depressive disorder that affects about 5% of adults in the United States. People with SAD experience mood changes and symptoms similar to depression. The symptoms usually occur during the fall and winter months when there is less sunlight and usually improve with the arrival of spring. SAD is more than just “winter blues.” The symptoms can be distressing and overwhelming and can interfere with daily functioning.^[7]

SAD has been linked to a biochemical imbalance in the brain prompted by shorter daylight hours and less sunlight in winter. As seasons change, people experience a shift in their biological internal clock or circadian rhythm that can cause them to be out of step with their daily schedule. SAD is more common in people living far from the equator where there are fewer daylight hours in the winter.^[8]

SAD can be effectively treated with light therapy, antidepressant medications, cognitive behavioral therapy, or some combination of these. While symptoms will generally improve on their own with the change of season, symptoms can improve more quickly with treatment. Light therapy involves sitting in front of a light therapy box that emits a very bright light (and filters out harmful ultraviolet [UV] rays). It usually requires 20 minutes or more per day, typically first thing in the morning during the winter months. Most people see some improvements from light therapy within one or two weeks of beginning treatment. For some people, increased exposure to natural sunlight can help improve symptoms of SAD by spending time outside or arranging their home or office space to increase exposure to windows during daylight hours. General wellness activities such as performing regular exercise, eating healthfully, getting enough sleep, and staying active and connected (such as volunteering, participating in group activities and getting together with friends and family) can also help.^[9]

Peripartum Depression

Pregnancy and the period after delivery can be a vulnerable time for women. Mothers can experience significant biological, emotional, financial, and social changes during this time. Up to 70 percent of new mothers experience the “baby blues,” a short-term condition that does not interfere with their daily activities and does not require medical attention. Symptoms include crying for no reason, irritability, restlessness, and anxiety. These symptoms generally last up to two weeks and resolve on their own.^[10]

However, as many as 3 to 6% of women experience a type of major depressive disorder during pregnancy (called perinatal depression) or after delivery (called postpartum depression).^[11] See Figure 7.6^[12] for an illustration of perinatal depression from the National Institutes of Health.

Postpartum depression includes feelings of extreme sadness, anxiety, and exhaustion that may make it difficult for these new mothers to complete daily care activities for themselves and/or for their babies. Untreated peripartum depression is not only a problem for the mother’s health and quality of life but can also affect the well-being of the baby. Postpartum depression can cause bonding issues with the baby and also contribute to sleeping and feeding problems for the baby. In the long-term, children of mothers with peripartum depression are at greater risk for cognitive, emotional, developmental and verbal deficits, and impaired social skills.^[13]

Severe postpartum depression can lead to postpartum psychosis, a medical emergency. Women who have postpartum psychosis may have delusions (thoughts or beliefs that are not true), hallucinations (seeing, hearing, or smelling things that are not there), mania (a high, elated mood that often seems out of touch with reality), paranoia, and confusion. Women who have postpartum psychosis are at risk for harming themselves or their child and should receive help as soon as possible by calling 911 or taking the mother to the nearest emergency room.

Mixed Features

Depressive episodes can also be classified as “mixed,” meaning they alternate with periods of manic symptoms such as euphoria, irritability, increased activity, increased talkativeness, racing thoughts, increased self-esteem, decreased need for sleep, distractibility, and impulsive reckless behavior.^[15] Characteristics and treatment of bipolar disorder are further discussed in the “Bipolar Disorders” chapter. See Figure 7.7^[16] for a comparison of the features of different types of mood disorders.

Depression Associated With Grief

People have difficulty coping with the death or loss of a loved one, job, or relationship. It is normal for feelings of sadness or grief to develop in response to such situations, but being sad is not the same as having depression. The grieving process is natural and unique to each individual and shares some of the same features of depression. Both grief and depression can involve intense sadness and withdrawal from usual activities with increased risk for suicide.

According to the American Psychiatric Association, grief and depression are different in these ways^[18]:

• In grief, painful feelings come in waves, often intermixed with positive memories of the deceased. In major depression, mood and/or interest (pleasure) are decreased for most of two weeks.
• In grief, self-esteem is usually maintained. In major depression, feelings of worthlessness and self-loathing are common.
• In grief, thoughts of death may surface when thinking of or fantasizing about “joining” the deceased loved one. In major depression, thoughts are focused on ending one’s life due to feeling worthless or undeserving of living or being unable to cope with the pain of depression.

Grief and depression can coexist. When grief and depression occur together, the grief is more severe and lasts longer than grief without depression. Nurses must be able to distinguish between symptoms of grief and depression and assist people in getting the help, support, or treatment they need.^[19]