Depression: definition, statistics and types

Depression is a common medical illness that can disrupt your life.


  • Depression is characterized by a persistent low mood that is often accompanied by inability to feel pleasure. In addition, a person may have problems eating, sleeping, working, and getting along with his/her friends.

  • If such feelings linger for more than two weeks and start interfering with your daily activities, then you may be suffering from a clinical depression.

  • Depression is highly treatable. People often respond well to available treatments, but no known cure exists.


  • According to the World Health Organization (WHO), 350,000,000 people are affected by depression worldwide.

  • In the US, approximately 16,000,000 adults have reportedly suffered from at least one major depressive episode (MDE) in 2012 alone. That is around 6.9 percent of the country’s total population.

  • Around 50% of those suffering from a clinical depression do not seek medical treatment.

  • According to the Centers for Disease Control, 41,149 suicides were reported in 2013. Therefore, the ratio of suicide deaths per 100,000 people is 13:100,000.

Types of Depression

  1. Major depression – Symptoms include interference with your capacity to sleep, work, eat or enjoy a normal life. People may have depressive episodes that can last weeks to months and may have such episodes multiple times in their life.

  2. Persistent depressive disorder – Previously known as dysthymia, this is a form of chronic depression with symptoms less severe but longer lasting than major depression. This form of depression may last as long as 2 years.

  3. Psychotic depression – This is a form of severe major depression that is accompanied by psychosis (psychosis is a condition in which a person loses contact with reality or is unable to think in an organized way).

  4. Postpartum depression – Many mothers experience “baby blues” during the first week or two after childbirth; but postpartum depression lasts longer and is more intense than baby blues and eventually interferes with your ability to care for your baby and handle other daily tasks. Around 10-15% mothers have postpartum depression after delivering a child.

  5. Seasonal affective disorder (SAD) – This is a type of depression in which people experience depressive symptoms primarily during the winter seasons.

    • This kind of depression can be effectively treated with light therapy.
    • In addition to light therapy, antidepressant medication and psychotherapy may also be helpful.

  6. Bipolar disorder – Bipolar disorder is characterized by extreme mood changes, including emotional lows (depression) and highs (mania or hypomania), that last for at least a few weeks at a time and may recur throughout the year. Bipolar disorder can be disruptive in many cases, and psychological counseling and medications can help minimize the amount of disruption this illness can cause.

  7. Atypical depression – This is a subtype of major depression which involves increased fatigue, sleepiness, weight gain and/or increased appetite. It usually affects people at an early age, particularly when they are in their teens.

  8. Premenstrual dysphoric disorder (PDD) – This is regarded as a severe form of premenstrual syndrome (PMS). It usually occurs in the second half of a woman’s menstrual cycle, especially during the days before the onset of the menstrual period.

Concluding words of wisdom

Clinical depression can affect any one of any age, including children. But with proper psychological counseling, administration of antidepressant medications or both, symptoms of clinical depression can be effectively treated. Family and friends can be of immense help in providing non-judgmental and empathic support. Hence, with a good support network and good psychiatric care, many people who suffer from this illness can and DO lead normal and meaningful lives.