Depression is a pervasive and debilitating mental health disorder that affects more than 300 million people, making it the leading cause of disability worldwide. It is also one of the most costly — in 2013 alone, $71 billion was spent on treating depressive disorders, and according to estimates from the World Health Organization, depression and anxiety disorders cost the global economy $1 trillion each year in lost productivity.
Depressive symptoms, such as anxiety, anhedonia, restlessness, and/or disrupted sleep patterns, are not always obvious and often present themselves in a gradual onset, making it difficult for those close to the patient to determine if he or she might be having a bad week or if these changes stem from something more. Symptoms are also highly variable in clinical presentation, often proving a challenge even for professionals to identify. While one person may withdraw to a point of apathy, others may become irritable or agitated by seemingly innocuous triggers. Sometimes, people show few outward signs at all. In many cases of mild depression, symptoms may not deviate considerably from those seen in healthy but stressed individuals, potentially leading clinicians to underestimate the severity of the patient’s depression or to believe psychological issues are not clinically significant.
A depressive episode can be classified as mild, moderate, or severe depending on the quantity and severity of symptoms. Someone experiencing a more mild form of depression might struggle with ordinary work and social activities, but will likely still be able to function somewhat normally. When a person is suffering from severe depression, it is highly unlikely that he or she will be able to continue with social, work, or domestic activities, except to a very limited amount. At its most extreme, depression can lead to suicide. Nearly 800,000 deaths are attributed to suicide annually, and it is the second leading cause of death among 15- to 29-year-olds. In 2017, the United States saw more than double the number of suicides (47,173) compared to homicides (19,510).
A few other relevant — and concerning — facts about depression:
- While depression can develop at any point in life and affect anyone, the median age at onset is 32.5 years old and women are more likely to be affected than men.
- Between 2005 and 2014 — with a marked uptick in 2011 — the prevalence of depression in U.S. adolescents aged 12 to 17 grew from 8.7% to 11.3%. This corresponded to a 37% increase in the odds of an adolescent becoming depressed. By 2017, an estimated 3.2 million U.S. adolescents aged 12 to 17 had experienced at least one major depressive episode — a number that represented 13.3% of the U.S. population in that age range.
- In 2016, patients diagnosed with depression in the U.S. had, on average, 163% more outpatient and emergency room visits, were written 214% more prescriptions, and had 227% more inpatient stays. This equated to a two-fold increase in average health care costs for those with depression (from $4,283 to $10,673).
- In developing countries, nearly 75% of people with mental disorders remain untreated, with almost 1 million people taking their lives each year.
- The number of people seen living with depression across the world rose by more than 18% between 2005 and 2015.
- Why is all of this happening? Why are so many people across the world suffering, and why does the problem just seem to be getting worse? It is often thought that depression is caused by a chemical imbalance in the brain, but this doesn’t even begin to capture the complexities of the disease. Depression results from a multifaceted interaction of social, psychological, and biological risk factors, often with several interacting at once to intensify and lengthen the duration of the illness.