Though everyone has some ‘down’ days, it is important to distinguish these feelings and depression. Depression is not sadness, grief, disappointment, or frustration – emotions in response to an event.
Depression is characterized by persistent sad or depressed moods, as well as some of the following features: significant changes in sleep and eating patterns, anxiety or restlessness, difficulty concentrating or making decisions, feelings of guilt or worthlessness, irritability, loss of interest in activities that previously were pleasurable, unusual worrying, and significant fatigue/exhaustion, etc. Physical health and depression are interrelated, for example cardiovascular disease can lead to depression and vice versa. People can experience depression for a prolonged time or episodically.
There are multiple causes of depression: changes in the body’s chemistry can influence mood and thought processes; biological factors; certain mental or emotional issues; and, familial tendencies. Some depressions originating from purely psychological causes have neurobiological effects and need medications in order to resume normal functioning, and conversely, some biologically predominantly depressions which have been treated with physical treatments may still require the use of psychological interventions.
Depression severity is on a continuum, yet the extremes have different qualities: severely depressed people show more cognitive symptoms such as worthlessness/guilt or suicidality compared to the moderately depressed, and the moderately depressed show more somatic indications, such as depressed mood compared to the severely depressed. Anxiety, restlessness, or agitation often accompany depression for some people. For others, exhaustion and fatigue are more predominant. Many people report feeling helpless or hopeless.
Each person experiences depression differently. Some people experience a few symptoms, some many. Depressed individuals frequently experience reduced functioning at work and/or home, as well finding their relationships are negatively affected. About 80% of adults with depression report at least some difficulty with work, home, or social activities. Social withdrawal is another common response for those who experience depression. The prevalence of depression in the U.S. is greatest among people aged 18-29 years, followed by those aged 45-64, and women experience depression nearly twice as much as men.
Depression is a common mental health problem and psychologists are highly trained in effective treatments.