Depression, also known as major depressive disorder, is a mental health disorder that negatively affects how a person feels, how a person thinks, and how a person acts. Depression is common and, fortunately, treatable.
Depression symptoms can range from mild to severe, including:
- A depressed mood or feeling of sadness
- Los of interest in activities once enjoyed
- Changes in appetite – weight loss or gain
- Trouble sleeping or sleeping too much
- Loss of energy or increased fatigue
- Increase in purposeless tasks or physical activities such as pacing
- Slowed movements and speech
- Feeling guilty or worthless
- Difficulty thinking or concentrating
- Suicidal thoughts
For depression to be diagnosed, symptoms must last at least two weeks. Some medical conditions, such as thyroid problems or vitamin deficiencies, can mimic symptoms of depression and need to be ruled out.
Depression affects about 1 in 15 adults in any given year, and 1 in 6 people will experience depression at some time in their life. Risk factors for depression include:
- Biochemistry: Differences in chemicals in the brain
- Genetics: Depression can be hereditary
- Personality: Those who are generally pessimistic or have low self-esteem are more likely to experience depression
- Environment: those who are exposed to violence, abuse (physical, verbal, emotional, etc.), neglect, or poverty are more likely to experience depression
Depression is one of the most treatable mental illnesses, and those who have been diagnosed have multiple options depending on their diagnosis.
- Anti-depressants may be prescribed to help modify one’s brain chemistry.
- Psychotherapy and/or cognitive behavioral therapy are often used to help individuals work through depression and are often combined with anti-depressants for moderate to severe depression.
- Electroconvulsive therapy (ECT) is a medical treatment most commonly used for patients diagnosed with severe depression who have not responded to other treatments. It involves a brief electrical stimulation of the brain while the patient is under anesthesia.
Depression Rates Around the World
An Our World In Data study estimates about 3.4% (margin of error makes this range 2-6%) of the global population has depression. This is about 264 million people worldwide.
According to WHO estimates, the ten countries with the highest prevalence of depression are:
- Ukraine (6.3%)
- United States (5.9%)
- Estonia (5.9%)
- Australia (5.9%)
- Brazil (5.8%)
- Greece (5.7%)
- Portugal (5.7%)
- Belarus (5.6%)
- Finland (5.6%)
- Lithuania (5.6%)
The ten countries with the lowest rates of depression are:
- Solomon Islands (2.9%)
- Papua New Guinea (3.0%)
- Timor – Leste (3.0%)
- Vanuatu (3.1%)
- Kiribati (3.1%)
- Tonga (3.2%)
- Samoa (3.2%)
- Laos (3.2%)
- Nepal (3.2%)
- Philippines (3.3%)
A nation’s culture can significantly impact its population's mental health and the availability of mental health treatment services. For example, while depression rates are relatively low in Japan, suicide rates are high for children and teens ages 10-19. This is most likely due to pressure to do well in school and work and conform to group norms.
The countries with the lowest rates of depression have just recently added mental health screening and treatment services to their health care infrastructure, which, in part, could explain the reason for the low depression rates. Conversely, countries with widespread access to quality health care, specifically mental health care services, could have high rates because of the availability of screening and treatment services. Additionally, certain depression symptoms are more common in some societies than others due to other factors.
While depression rates are rising around the world, treatment is becoming more available and accessible. Rising depression rates are also attributed to more people seeking and receiving a diagnosis and treatment for mental illness, rather than going undiagnosed. For example, in the United States and several countries, the stigma surrounding mental illnesses has gradually decreased. This allows it to become more normal to discuss mental illness openly and encourages people to seek help when they need it.
An estimated 17.3 million adults in the United States had a least one major depressive episode in 2017. Among those diagnosed with depression, about 65% received treatment. About 50% of U.S. adults diagnosed with depression are also diagnosed with anxiety. Oregon, West Virginia, and Maine have the highest depression rates.