Everyone feels sad or down at times, especially after experiencing a disappointment such as not getting the job you interviewed for. However, these feelings of sadness are usually short-lived.
Depression, on the other hand, is a medical condition characterized by long-lasting feelings of intense sadness and hopelessness associated with additional mental and physical changes. Depression can affect someone's personal, social, and professional life.
About 1 in 5 women and 1 in 10 men will suffer from depression at some point in life. Depression in children and adolescents occurs less commonly than in adults. Almost 3 million Canadians have serious depression at any given time, but less than one-third of these people seek medical help.
Types of Depression
There are several different types of depression, and the diagnosis is mostly determined by the nature and intensity of the mental and physical symptoms, the duration of the symptoms, and the specific cause of the symptoms, if that is known.
Clinical depression (or major depressive disorder, MDD) is the most serious type of depression in terms of the number and severity of symptoms, but there are significant individual differences in the symptoms and severity. People affected with major depression may not have suicidal tendencies and may never have received medical treatment. The person's interest and pleasure in many activities, energy levels, and eating and sleeping patterns are usually altered.
Dysthymia refers to a low-to-moderate level of depression that persists for at least 2 years, and often longer. While the symptoms are not as severe as in major depression, dysthymia can still have a major impact on a person's quality of life. It is often not recognized that dysthymia is a medical condition that responds equally effectively to the same treatments as major depression. Some people with dysthymia develop major depression at some time during the course of their depression.
Bipolar disorder (or manic depression) includes both high and low mood swings and a variety of other significant symptoms not present in other types of depression.
Other types of depression include seasonal affective disorder (SAD), depression with psychosis, and postpartum depression.
- SAD is a subtype of depression that regularly occurs at the same time of year (most often in the fall or winter months in North America).
- Depression with psychosis occurs when depression is severe and is associated with hallucinations (hearing or seeing things that are not there) or delusions (thoughts that are not based in reality).
- Postpartum depression often begins a few weeks after giving birth and is a subtype of depression. Postpartum depression is different from the temporary state known as the "baby blues" that often happens 24 to 72 hours after a woman gives birth. This temporary state is caused by the hormonal changes that occur during pregnancy and after giving birth and typically resolves in a week or so. Postpartum depression lasts longer than the "baby blues" and interferes with the woman's emotional and social functioning.
In some cases, depression is associated with other chronic medical conditions, which negatively impact the person's quality of life and well-being.
There is no single cause of depression. Rather, it usually results from a combination of factors such as an imbalance of brain chemicals, family history, thoughts or beliefs that increase the risk of depression, and traumatic or stressful life events.
One factor involved in depression is an imbalance of the chemicals that help send messages in the brain. These chemicals in our brain also help regulate our emotions, behaviours, and thinking. How we perceive the world and what happens to us can also contribute to depression.
Depression has a genetic component (i.e., family history). While the tendency to be depressed can be genetically inherited, the onset of depression can be provoked by many factors.
Triggers of depression include:
- difficult or traumatic life changes (such as losing a loved one, ending a relationship, losing a job)
- medical conditions such as Parkinson's disease, stroke, lupus, hypothyroidism, chronic pain, and some types of cancer
- use of certain medications, including corticosteroids, anabolic steroids, narcotics, benzodiazepines, progesterone (found in some female hormonal pills), and street drugs such as amphetamines
- alcohol, which has short-term and possibly long-term depressive effects
It is important to recognize that depression is not something you can "get over" on your own, and it is not the result of personal weakness or an inability to cope.
Symptoms and Complications
Although we all feel sad sometimes, clinical (major) depression is diagnosed when a person experiences at least 5 of the symptoms below (one of which must be depressed mood or loss of interest or pleasure in daily activities), on most days for at least 2 weeks:
- depressed mood (sadness)
- loss of interest or pleasure in daily activities
- changes in appetite or weight
- fatigue or loss of energy
- insomnia (trouble sleeping) or chronic oversleeping
- noticeable changes in activity level (agitated or slowed down)
- feelings of worthlessness or guilt
- difficulty concentrating or making decisions
- recurring thoughts of death or suicide
Other symptoms of depression may include:
- loss of interest in work and other activities
- avoiding family members and friends
- crying easily
- hallucinations (hearing or seeing things that aren't there)
- delusions (having thoughts that are not based on reality)
- body aches and pains, such as headache, joint pain, or abdominal pain (these symptoms may be reported rather than feelings of sadness)
Clinical depression may vary in its severity, and in its extreme forms (i.e., thoughts of suicide) it can be life-threatening and require immediate medical attention.
Symptoms of other forms of depression, although generally milder, may still negatively affect a person's daily activities and quality of life.
Making the Diagnosis
To diagnose depression, your doctor will ask you questions about the symptoms you are experiencing and their severity. Your doctor may perform a physical exam and order blood tests to make sure there isn't an underlying medical cause for your symptoms.
Physicians are trained to help you, and to take depression and its treatment seriously. Together with your doctor, you can begin to identify and manage the nature of the problem, and then develop a treatment plan. This may include a referral to a psychiatrist or psychotherapist.
Treatment and Prevention
Most types of depression respond to antidepressant medications, psychotherapy, or a combination of both. Providing education about depression and its treatment to people with depression and to their family members may also be part of a treatment plan.
Medications: Sometimes people with depression are unaware that medications can help them, or they are at first hesitant to take antidepressant medications to manage their condition. However, there are many different medications available today to help treat depression. You and your doctor can work together to decide what medication is best for you.
Some of the more commonly used medications for depression include SSRIs (selective serotonin reuptake inhibitors such as fluoxetine*, paroxetine, citalopram, and escitalopram), SNRIs (serotonin-norepinephrine reuptake inhibitors such as duloxetine, venlafaxine, and desvenlafaxine), bupropion, trazodone, mirtazapine, MAOIs (monoamine oxidase inhibitors such as moclobemide and phenelzine), and tricyclic antidepressants (e.g., amitriptyline, doxepin, nortriptyline).
Medications used to treat depression begin to work after 2 to 4 weeks of treatment, although improvements in some symptoms may be seen within the first few weeks. In some situations, more than one medication will need to be tried until the most appropriate one is found for an individual. All medications, including antidepressants, can have side effects. Your doctor and pharmacist should explain common side effects to you and help you to manage them should they occur. Most antidepressants should be taken for at least 6 to 24 months after the episode of depression has resolved.
Herbals: Studies have shown that St. John's wort is not effective for people with clinical (major) depression. Although people with mild symptoms may receive some benefit from it, you should talk to your doctor and pharmacist before taking any herbals or over-the-counter medications. Keep in mind that some herbal medications may interact with prescription or over-the-counter medications.
Psychotherapy: Psychotherapy can be an important part of managing depression. Psychiatrists, psychologists, and some family doctors are trained to help people recognize and overcome the kind of thinking that causes depression. Support groups, friends, and family can also help.
- In more severe cases, electroconvulsive therapy (ECT) is used, but it is generally reserved for those who do not respond to medications.
- Light therapy (or "phototherapy," which involves controlled exposure to artificial sunlight) can help some people overcome symptoms associated with seasonal affective disorder.
- Physical activity and sports can improve depression by helping to relieve anxiety, increase appetite, aid sleep, and improve mood and self-esteem. Exercise also increases the body's production of endorphins, a natural mood-elevating hormone.
- An active lifestyle, supportive family and friends, and a positive outlook can go a long way in coping with depression.
*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For information on a given medication, check our Drug Information database. For more information on brand names, speak with your doctor or pharmacist.