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Definition of Depression

Depression is a chronic and recurrent mood disorder characterized by reduced functioning in more than one major area of life i.e. academic, familial, and peer relationships.

Epidemiology of Depression

According to the world health organization statistics, 350 million people worldwide suffered from depression in 2015.

3 million teenagers in the United States had at least one major depressive episode in the year 2015. One in every 6 people experiences depression at least once in a lifetime. Women are more likely to suffer from depression than men.

Major depressive episode

A major depressive episode is defined as the presence of 5 or more symptoms of depression lasting for two consecutive weeks.

Major depressive disorder

2 or more major depressive episodes are an indication of major depressive disorder.

Risk Factors for Depression

Social factors:

  • Family history of depression (Individuals whose parents have depression are 3 to 4 times more likely to suffer from depression than those with healthy parents)
  • Parental neglect
  • Bullying
  • Issues related to family relationships
  • Negative life events
  • Peer rejection

Psychological factors:

  • Pessimistic personality and low self-esteem
  • Exposure to violence and abuse
  • Poor socioeconomic status

Biological factors:

  • Major mental or physical illness
  • Physical abnormalities
  • Major hormonal imbalances at puberty
  • Low brain levels of serotonin


Two individuals experiencing similar circumstances may react to a situation in a different manner. One may develop depression while the other may not. Even in the presence of risk factors, some people cope well and avoid depression. This ability is termed ‘resilience’. High intelligence, an emotionally stable personality, coping skills, healthy family relationships, and peer support are positive resilience factors.

SIGECAPS — Symptoms of depression

S — Sleep disturbance

I — Loss of interest in different activities

G — Guilt

E — Loss of energy

C — Loss of concentration

A — Appetite changes

P — Psychomotor agitation

S — Suicidality

Other symptoms

  • Rebellious behavior
  • Use of alcohol or drugs
  • Promiscuous sexual activities
  • Crying episodes
  • Sadness and tearfulness
  • Hopelessness
  • Persistent boredom
  • Social isolation
  • Poor communication
  • Low self-esteem
  • Sensitivity to failure or rejection
  • Irritability
  • Frequent headaches, back pain, and stomachaches
  • Decline in academic performance
  • Apathy
  • Difficulty with relationships
  • Forgetfulness
  • Weight loss or weight gain
  • Changes in eating habits/eating disorders
  • Efforts to run away from home
  • Self-destructive behavior
  • Substance abuse majorly alcohol and smoking

Physical findings

  • Changes in body weight
  • Signs of self-injury


The diagnosis is based on interview questions. Symptoms of depression must be present for at least two consecutive weeks.

There are several questionnaires that can be used for screening depression in adolescents:

  • Two-item patient health questionnaire (PHQ-2)
  • Short mood and feelings questionnaire
  • Children’s depression inventory

Differential diagnosis

  • Adjustment disorder
  • Dysthymic disorder
  • Bipolar disorder
  • Schizophrenia

The differential diagnosis should also include medical conditions that can mimic depression including thyroid imbalances, CNS lesions, anemia, vitamin deficiencies, and obstructive sleep apnea.


Approximately two-thirds of individuals with depression who have at least one comorbid psychological condition will commit suicide when depressed. 10 to 15 percent of the individuals who have 2 or more comorbid conditions will have 2 or 3 suicide attempts. There is a 3 to 6 times higher probability of substance abuse in patients with depression.

Some comorbid conditions include:

  • Syndrome of severe mood dysregulation
  • Generalized anxiety disorder

As well, autism spectrum disorder, eating disorders, and attention deficit hyperactivity disorder (ADHD) are likely to become more pronounced in the presence of depression.

Individuals with depression are more at risk of developing disruptive behavior disorder and anxiety issues.


  • Cognitive-behavioral therapy (CBT)
  • Interpersonal psychotherapy (IPT)
  • Antidepressants): SSRIs (selective serotonin reuptake inhibitors) are a preferred selection for treatment; medication should be continued for at least 6 months even after the symptoms have improved.
  • Electroconvulsive Therapy (ECT); this the brief electrical stimulation of the brain under anesthesia. ECT is typically reserved for severe cases of depression which fail to respond to other treatment options.
  • Patient Health Questionnaire (PHQ-9) can be used to monitor the response to treatment.
  • Comorbidities like anxiety, eating disorders, and substance abuse are treated separately.

Overview of the treatment of depression

Psychotherapy Medications Manage comorbidities
  • Cognitive-behavioral therapy
  • Interpersonal therapy
  • SSRIs (preferred treatment)
  • Other antidepressants to increase the availability of monoamine neurotransmitters
  • Tricyclic antidepressants (risk of cardiotoxic side effects and overdose potential)
  • Substance abuse disorders
  • Eating disorders
  • Anxiety


Following activities can help improve depression:

  • Regular exercise
  • Healthy diet
  • Abstinence from alcohol and smoking
  • Abstinence from mobile and television overuse or misuse
  • Improved sleep quality


Suicide is the third leading cause of death among young people between the ages of 15 and 24. The suicide rate in young girls is higher than in boys.

Common Methods used in suicides

  1. Firearms
  2. Suffocation
  3. Poisoning

Risk factors

Some of the risk factors identified by researchers are as follows:

  • Previous suicide attempts
  • Behavioral changes such as increases in irritability or complete isolation from society
  • Eating disorders
  • History of substance abuse such as alcohol or smoking
  • History of sexual or physical abuse
  • Low self-esteem
  • Depression, anxiety, and other health problems
  • Stressful life events, either social or academic
  • Loss of a loved one
  • Ease of access to lethal drugs
  • History of self-harm such as cutting or biting oneself
  • Mental illness
  • Family history of suicide
  • Lack of social and family support

Protective factors / Preventive measures

  • Reflective and deep thinking skills
  • Community programs for mental illness and substance abuse disorders
  • Ease of access to psychiatric help through regular supportive counseling sessions
  • Support from friends and family
  • Cultural programs that discourage suicide
  • Religious beliefs (monistic faith in god and religious activities)
  • Indulging in constructive activities such as sports or artistic pursuits such as painting and drawing

All adolescents should be monitored for signs of depression, substance abuse, or suicidal tendencies as together these are the third leading cause of death in adolescents. Prevention programs are available that target risk factors to help reduce adolescent mortality and enhance well being, such as the national suicide prevention line.

National Suicide Prevention Lifeline
Call 1-800-273-8255
Available 24 hours everyday
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