Major Depressive Disorder (Depression)


Major depressive disorder (MDD) is characterized by feelings of sadness, loss of interest and worthlessness. They can significantly affect our health and our lives, if left untreated. Let’s take a look at what MDD is and how you can deal with it.

What Is Major Depressive Disorder?

Major Depressive Disorder (Depression)

Major depressive disorder (MDD), generally known as depression, is a mood disorder resulting in chronic sadness, a sense of despair, low mood, irritability, insomnia, lethargy and even suicidal thoughts. MDD is different from general feelings of sadness as episodes can last for two weeks. Unlike mood fluctuations, MDD can require weeks, months or even years of treatment. According to a research paper 1 , “Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest.”

MDD, also known as clinical depression, unipolar depression and major depression, greatly affects how an individual thinks, feels, behaves and acts leading to different emotional and physical issues. A person with MDD may feel hopeless and think that life is not worth living. This can affect their daily life and lead to suicidal tendencies.

Major Depressive Disorder At A Glance 

  1. Major depressive disorder (MDD), generally known as depression, is a mood disorder resulting in chronic sadness, a sense of despair, low mood, irritability, insomnia, lethargy and even suicidal thoughts.
  2. Major depression is a psychiatric disorder that not only affects your thinking, mood & behavior, but also our physical wellbeing.
  3. MDD is also believed to affect and alter regions of the human brain which help to regulate mood.
  4. Major depressive disorder is commonly treated by a combination of medication, psychotherapy and support from family and friends.
  5. Major depression is a real mental illness which can be effectively treated with prompt diagnosis and treatment

Prevalence Of Major Depressive Disorder

According to research 2 , MDD is a highly prevalent condition with an average lifetime prevalence of about 12%. However, 12-month prevalence of the disorder is around 7% with significant differences observed in age groups. The researchers also found that major depressive disorder is “more common in people without close interpersonal relationships, and who are divorced or separated, or widowed.” However, differences were not observed among different socioeconomic status or races. The research also reveals MDD is ranked as the “third cause of the burden of disease worldwide” by the World Health Organization (WHO) in 2008.

People suffering with this disorder are prone to developing certain comorbid disorders, like obsessive compulsive disorder, social anxiety disorder, panic disorder and substance use disorders. These co-occurring conditions can further increase the likelihood of suicidal thoughts and behavior in sufferers.

Understanding Major Depression

Certain devastating life events like losing a loved one, serious illness, getting a divorce or a breakup, unemployment or life challenges can often make us feel sad temporarily. However, when such feelings of sadness persist for an extended period of time, then it may be considered as MDD by mental health professionals.

Major depression is a psychiatric disorder that not only affects your thinking, mood & behavior, but also our physical wellbeing. Those affected may experience low energy, low self-esteem, aches and pains without any probable reason and loss interest in activities they used to enjoy earlier. It can also affect their ability to study, work, eat, sleep and socialize. Certain individuals experience MDD once in a lifetime, whereas others may experience various episodes throughout their life. MDD is also the primary reason for disability across the globe, according to the WHO.

Thankfully, major depressive disorder has been thoroughly studied and understood by mental health professionals and is a treatable condition. People with MDD can recover fully with the help of therapy and medication. Unfortunately, most people suffering from major depression do not seek treatment to cope with their symptoms.

Types Of Depression

Major Depressive Disorder (Depression)

There are different types of major depressive disorders which are subtly different from each other and may develop under different circumstances. However, all types of MDD involve the same feelings of unhappiness, hopelessness and disinterest. According to National Institute of Mental Health (NIMH), some of the most common types of depression are:

1. Persistent depressive disorder (Dysthymia)

It refers to a form of depression that lasts for at least 2 years. Someone suffering from this clinical disorder has a depressed mood and may experience episodes of both major and mild depression.

2. Postpartum depression

Most women experience this type of depression after giving birth. It is a lot more severe than baby blues after pregnancy. It is a form of major depression that leads to intense feelings of sadness and anxiety after delivery. It can often make daily baby care activities extremely challenging for new mothers.

3. Psychotic depression

It is a form of major depression along with some type of psychosis like having hallucinations or delusions. The symptoms of this condition generally have psychotic and depressive themes.

4. Seasonal affective disorder (SAD)

SAD 3 usually refers to the onset of a depressive state during the winter months. As there is less sunlight, many people become severely depressed, which usually alleviates as spring and summer arrives. It is often followed by social isolation & withdrawal, weight gain & increased sleep.

5. Bipolar disorder

Bipolar disorder is separate from depression, as stated in the fifth edition of the Diagnostic and Statistical Manual of Mental Health Disorder (DSM-5). However, studies 4 have found that both depression and bipolar disorder have similar symptoms, like episodes of intensely low moods and high energy. As a result, it is often difficult to distinguish MDD from bipolar disorder.

Apart from these, there are some other common types of depression which includes:

  • Catatonic depression
  • Disruptive mood dysregulation disorder
  • Depressive disorder due to other medical conditions
  • Melancholic depression
  • Premenstrual dysphoric disorder
  • Substance/medication-induced depressive disorder
  • Other specified and unspecified depressive disorder

Read More About Types Of Depression Here.

How Major Depressive Disorder Affects Us?

People suffering from MDD are affected in a variety of ways. Not only do they experience low mood, they may also have stress and anxiety. They are also prone to worry excessively about their physical health. A depressed individual may have difficulty in functioning effectively at school or work, have frequent conflicts in relationships and are prone to substance abuse. Moreover, this condition may also affect their sexual drive and functioning.

Major depression is also believed to affect and alter regions of the human brain which help to regulate mood 5 . Nerve cells in specific areas of the brain function ineffectively, which affects the communication between nerve circuits. This makes it difficult for an individual to control their mood. Changes in hormones can also affect mood adversely. Major traumatic life experience often affects our biological processes. Our genetic structure also determines how we might be affected by this mental condition.

People with major depressive disorder can experience hallucinations, false perceptions, delusions and other “psychotic symptoms” during a depressive episode. However, they can also have episodes when they feel highly irritated or even energetic. If a person suffers from depression, then they are more likely to experience a disrupted sleeping pattern or experience insomnia.

A person may become vulnerable to this mental illness at any age. Individuals with family members suffering from major depression are highly likely to become depressed or abuse alcohol and other substances.

Depression Facts

According to the World Health Organization 6 (WHO), over 264 million individuals of all ages suffer from depression across the world. More women than men are affected by depression. As per the CDC 7 , 10.4% of American women were diagnosed with depression as compared to 5.5% of American men. Research shows that lifetime rates in developed nations is around 15%, which is relatively higher than that of developing countries at 11%.

The 2017 National Survey on Drug Use and Health 8 showed that 7.1% (17.3 million) of adults in the United States had experienced a major depressive episode in the previous year. Moreover, around 8,00,000 people commit suicide each year, according to WHO. Suicide is second biggest cause of death for people between 10-34 years of age.

Causes Of Major Depressive Disorder

Major Depressive Disorder (Depression)

Medical professionals are yet to fully understand the exact causes of major depressive disorder. However, research 9 suggests that this mental condition is likely caused by a combination of factors, like:

  • Genetic factors
  • Biological factors
  • Environmental factors

1. Genetic factors

According to the American Psychiatric Association (APA), depression can be an inherited condition. If you have a family member who suffers from depression, then it is highly likely that you will develop major depression sometime in your life. Research 10 shows that a person is twice more likely to suffer from major depression if they have a grandparent or a parent with depression.

The APA also states that “if one identical twin has depression, the other has a 70 percent chance of having the illness” at some point in their life. Moreover, studies on families and twins reveal that risk for developing MDD can be explained about 40% due to genetic factors 11 . A 2019 study 12 identified 102 variants in the genome linked to risk for major depression.

2. Biological factors

Major Depressive Disorder is a serious medical illness and is distributed across several brain regions and circuits 13 . Hence, substantial changes in the human brain may lead to depression in some people. Brain chemistry and brain function 14 can be a notable cause for MDD. Neurotransmitters, like norepinephrine, dopamine and serotonin, can influence our emotions. As it can put feelings of happiness and joy out of balance, this may lead to a depressive state. But why neurotransmitters become disbalanced and how they lead to major depression is not fully understood.

Moreover, hormonal changes or varying hormone functioning may also lead to depression. Thyroid problems, childbirth, menopause and different disorders can result in hormonal changes, leading to depression.

3. Environmental factors

According to the APA, major depressive disorder can occur due to constant exposure to violence, abuse, trauma, neglect or poverty. People who have experienced adverse events in life, like loss of a loved one 15 , unemployment, relationship problems, financial issues, serious illness or childhood trauma 16 are highly vulnerable to developing depression. Different physical illnesses, like cardiovascular disease, Parkinson’s disease and cancer, may also result in depression.

Apart from these, there may be various other factors that can contribute to the development of MDD in an individual:

  • Lifestyle changes
  • Social isolation
  • Separation or abandonment
  • Personal conflicts in relationships
  • Changes in appetite or poor nutrition
  • Circadian rhythm disturbances
  • Alcohol or drug abuse
  • Excessive stress
  • Physical, emotional & sexual abuse
  • Personality issues like low self-esteem & pessimism
  • Major life events

Read More About Causes Of Depression Here.

Symptoms Of Major Depressive Disorder

Symptoms Of Major Depressive Disorder
Major Depressive Disorder (Depression)

A person suffering from major depression will experience the following signs and symptoms for at least two weeks, almost every day, as specified by the DSM-5 and ICD-10:

1. Psychological symptoms:

  • Persistent sadness
  • Low mood & worrying
  • Stress, anxiety & frustration
  • Feelings of hopelessness & worthlessness
  • Irritability & agitation
  • Feelings of guilt
  • Pessimism and helplessness
  • Loss of interest in pleasurable activities
  • Difficulty in concentrating & making decisions
  • Memory problems or difficulty in remembering details
  • Angry outbursts over small issues
  • Poor performance at work or school
  • Drug and alcohol abuse
  • Suicidal thoughts and tendencies

2. Physical symptoms:

  • Reduced energy, constant exhaustion & fatigue
  • Lethargy
  • Feelings of restlessness
  • Slowed thinking, talking or body movements
  • Difficulty sleeping or insomnia
  • Changes in appetite
  • Weight loss or gain
  • Digestive problems
  • Headaches
  • Aches or pains due to unknown reasons

Apart from these, some individuals may also experience fluctuations in motor abilities, have psychotic episodes and show signs of mania. However, not each and every person suffering from major depressive disorder will experience all the symptoms. Some may experience almost all of them, while others may experience only a few.

Diagnosis Of Major Depression

Major depression is usually diagnosed by a mental health professional or a primary care physician. After analysing the patient’s medical history, the health professional will perform an evaluation of the symptoms by asking certain questions. However, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5 17 ), a person needs to exhibit at least five or more symptoms of MDD nearly every day for at least two weeks to be diagnosed as depressed. Moreover, the professional may also assess the patient’s personal and family psychiatric history.

Currently, no specific tests are conducted to diagnose depression. However, a primary care physician may run certain tests to determine if the symptoms are being caused by any other medical problems or medication.

Treatment Of Major Depressive Disorder

Many people suffering from major depression do not seek any treatment. According to a study published in The British Journal of Psychiatry, only one in five people in the richest countries seek treatment for depression, whereas only one in 27 people in the poorest countries seek help. This is perhaps due to the stigma attached to mental health and the attitude of our society towards depression. Moreover, the patient’s ability to recognize the condition and seek help may be distorted due to the mental illness. Hence, friends and family play a crucial role when it comes to encouraging individuals to seek treatment.

Fortunately, depression is one of the most treatable mental conditions. According to the APA, around 80-90% of patients respond well to treatment. Moreover, almost every patient has reported that they have experienced some relief from symptoms of MDD. Major depressive disorder is commonly treated by a combination of medication, psychotherapy and support from family and friends.

1. Medications

A mental health professional may begin treatment for depression by prescribing antidepressant medications. Different types of antidepressants may be recommended by the healthcare provider depending on the individual and the severity of the condition:

  • Atypical antidepressants
  • Monoamine oxidase inhibitors (MAOIs)
  • Selective serotonin reuptake inhibitors (SSRIs 18 )
  • Selective serotonin and norepinephrine reuptake inhibitors (SNRIs)
  • Tricyclic antidepressants

Antidepressants can substantially help in treating moderate-to-severe depression. Each type of medicine focuses on a specific neurotransmitter. These medicines improve how our brain processes specific chemicals which regulate stress and mood. However, SSRIs and SNRIs can have certain side effects like diarrhea, constipation, nausea, weight loss, low blood sugar and sexual dysfunction.

The patient may start experiencing the benefits after the first 2-4 weeks, but for the antidepressants to be fully effective, the medicine needs to be taken for at least 2-3 months. It is crucial that the patient speaks with their doctor if they do not experience any improvements or experience any side effects.

However, antidepressants should be taken by patients only when they are prescribed by their doctors. If someone stops taking the medication once the symptoms start to improve, then it can result in a relapse. It should be noted that medications for the treatment of MDD are not safe for pregnant women or mothers who are breastfeeding. Moreover, children, adolescents and young adults may experience increased suicidal tendencies in the initial weeks when taking antidepressants. Hence, the patient should be observed closely at all times.

2. Psychotherapy

Psychological therapy or talk therapy can be a helpful treatment option for major depressive disorder. It includes therapy techniques like cognitive behavioural therapy (CBT), interpersonal psychotherapy, problem-solving treatment and others. Therapy requires that the patient interacts with the therapist regularly and talks about their condition, how they feel and related problems. A combination of psychotherapy and medications can enable a person with major depressive disorder to recover fully. In fact, CBT has proven to be highly effective in treating depression 19 . However, the duration of the treatment depends on the severity of the condition and may last from few weeks to few months.

Psychotherapy can help an individual to:

  • Cope with emotional problems
  • Accept and adjust to stress or a crisis
  • Remove negative thoughts and behaviors and build positive ones
  • Understand how depression affects their mood
  • Improve communication and relationships
  • Cope better with problems & challenges
  • Boost self-esteem
  • Regain control in their life

3. Electroconvulsive therapy (ECT)

If medications and psychotherapy proves ineffective, then a mental health professional may recommend Electroconvulsive Therapy (ECT 20 ) to relieve the symptoms of major depressive disorder. ECT is commonly used for people with severe major depression or bipolar disorder, especially those who do not respond well to other types of treatment. It requires the doctor to put the patient under anesthesia and apply brief electrical stimulation to the brain.

Treatment involves a number of sessions, generally two to three times a week for a period of two to four weeks. Although it may cause some short-term side effects, ECT is not painful. It is an effective and safe treatment option for a majority of depression patients.

Read More About Treatment Of Depression Here.

Self-help And Coping

People who suffer from major depressive disorder can benefit a lot by educating themselves about the mood disorder. Not only will it enable them to understand their condition and how it affects them, they will also be able to utilize a number of self-help strategies to help them relieve the symptoms.

There are several coping strategies that can enable people with MDD to reduce the symptoms. However, self-help techniques for coping with depression prove to be most effective when used along with medication and therapy under the guidance of a mental health professional.

Here are some self-help tools that can help someone with major depression to cope with the illness:

Major Depressive Disorder (Depression)

1. Lifestyle changes

Changing daily habits can help to improve symptoms of major depressive disorder. By replacing bad habits with healthier ones, an individual can develop a positive mindset & improve mood overtime. By setting realistic goals and continually educating themselves about depression, a person can improve their mood gradually.

Moreover, getting quality sleep and avoiding smoking & alcohol can also help in reducing symptoms of major depressive disorder.

2. Exercise

Physical exercise has been proven to be highly effective and can improve treatment outcomes 21 for depression patients, when teamed with cognitive-behavioral therapies. Exercising regularly can greatly help with managing 22 major depression and is considered to be an effective alternative 23 to medication and therapy. Moreover, relaxation breathing exercises 24 , yoga 25 , meditation 26 and mindfulness 27 practices have also been proven to be helpful in alleviating the symptoms of MDD.

3. Diet and nutrition

Food plays a crucial role when it comes to mental health and depression. According to a 2019 study, a diet intervention can help to relieve depression symptoms in young adults. The study found that symptoms of depression can reduce by adding the following foods into a person’s regular diet:

  • Fish
  • Fruit
  • Vegetables
  • Olive oil
  • Wholegrain cereals
  • Protein (lean meat, poultry, eggs)
  • Unsweetened dairy
  • Nuts and seeds spices (turmeric and cinnamon)

4. Support

The support of family and friends can play a big role in the patient’s recovery from major depressive disorder. Not only should the patient’s loved ones educate themselves about depression, but they should also encourage the patients to seek and continue treatment. Moreover, talking to a trusted family member or friend can also help to lift their mood. The patient should also avoid isolating themselves and allow others to provide support.

Read More About Coping Strategies For Depression Here.

Help Is Available

Major depression is a real mental illness which can be effectively treated with prompt diagnosis and treatment. If you or someone you know is suffering from depression, then the first thing to do is visit a primary care physician or a mental health professional. But it is also important to stick with the treatment program to improve their perspective, recover fully and live a happier and better life.

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Major Depressive Disorder (Depression) Reviewed By :

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