What is major depressive disorder?

While the term “depression” or “depressed” is sometimes used as a general term for feeling sad, major depressive disorder refers to a more severe and persistent form of depression. It is also referred to as “major depression” or “clinical depression” by healthcare professionals.

A major depressive episode is defined as experiencing five or more of the following symptoms, one of which must be either depressed mood or loss of interest/pleasure in everyday activities, most days and most of the day for at least two weeks. These are a change from normal, are severe enough to interfere with a person’s day-to-day function and are not better explained by a different disorder or condition.

The symptoms are:

• depressed mood most of the day; feeling sad, hopeless or empty
• loss of interest or pleasure in almost all activities
• significant changes in appetite or unplanned weight changes
• disturbed sleeping (too little or too much)
• noticeable changes in mental and physical activity levels, either agitation and restlessness, or a slowing down
• fatigue or loss of energy
• feelings of guilt or worthlessness, or a loss of self-confidence
• difficulty concentrating, remembering, or making decisions
• frequent thoughts of death or suicide, especially in older men

Other signs and symptoms are also frequently seen, such as feelings of anxiety, irritability, or physical symptoms such as unexplained aches and pains, headaches, cramps, or digestive problems.

Depression in older adults may be hard to detect. Common symptoms such as fatigue, appetite loss, and trouble sleeping can be part of the aging process or a physical illness. As a result, symptoms of early depression may be ignored or confused with other conditions that are common in older adults.

How is depression assessed?

See your healthcare provider if you've been experiencing signs or symptoms of depression. A comprehensive assessment will include a detailed history of your symptoms and current stressors, as well as your medical history, any medications you’re taking, substance use, prior history of mental health issues, and your family psychiatric history. It may also include the use of standardized questionnaires, physical examination, and lab tests, if needed, to rule out other medical causes of depressive symptoms.

How is depression treated?

There are many effective treatment approaches for depression, including non-medication treatments like psychotherapy (or ‘talk therapy’), medications (typically antidepressants), self-help techniques (such as meditation or yoga) and other medical treatments that stimulate the brain like electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS). You can also do things for yourself to help, like behavioural activation techniques, exercise and physical activity, yoga, or light therapy.

Follow-up is important to ensure that you're responding to your treatment and that you eventually recover.