What is depression?
What are the types of depression?
According to the American Psychiatric Association’s Diagnostic Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) depressive disorders are classified into
- Disruptive mood dysregulation disorder
- Major depressive disorder
- Persistent depressive disorder (dysthymia)
- Premenstrual dysphoric disorder
- Depressive disorder due to another medical condition
Disruptive mood dysregulation disorder
A condition in which the children or adolescents experience continued irritability, anger and frequent temper outbursts which are severe and beyond expectations.
Major depressive disorder
When an individual persistently has low mood, lack of interest in pleasurable activities, feeling of guilt and worthlessness, poor concentration and suicidal thoughts are considered major depression.
Persistent depressive disorder (dysthymia)
When the depressive symptoms last for many years and interfere with your relationships, work and daily activities.
Depressive disorder due to another medical condition
Certain diseases like stroke, hypothyroidism, Parkinson’s disease and traumatic brain
the injury also causes persistent or predominant depressed mood.
What are the causes of depression?
The leading causes include
- Changes in brain chemistry: chemical imbalance in parts of the brain that controls mood, sleep and thoughts
- Early childhood trauma
- Family history
- Medical conditions like stroke, cancer, heart attack and Parkinson’s disease
- Substance abuse with alcohol, narcotics
- Emotional pain or chronic pain associated with the disease that lasts for a longer duration
- Post-partum, menstrual, or menopause fluctuations in estrogen or progesterone hormones.
What are the risk factors of depression?
- Being a women increase chances of depression
- Genetic factors and family history
- Socioeconomic statuses like financial problems and low social status
- Use of certain medications such as birth control pills, corticosteroids and beta blockers
- Lack of vitamin D
- Substance abuse
What are the signs and symptoms of depression?
General signs and symptoms
- A feeling of worthlessness and hopelessness
- Feeling bothered and annoyed
- Decresed energy or fatigue
- Thoughts of death, suicide or self-harm
- Moving or talking slowly
- Reduced appetite
- Difficulty in sleeping, or oversleeping
- Loss of interest in hobbies
- Experiencing physical issues like headaches, stomachache and sexual dysfunction
How is depression diagnosed?
There are no diagnostic tests available for depression. It is diagnosed mainly based on physical findings and medical history. However certain lab tests may be useful to exclude the medical illness that may present as major depressive disorder. This includes the following like:
- Complete blood count
- Thyroid-stimulating hormone (TSH) test
- Electrolytes like calcium, phosphate and magnesium
- Blood alcohol level
- Vitamin B12
- Liver function
- Blood urea nitrogen and creatinine test
How is depression treated?
Almost 80-90% of people who seek treatment for depression respond to the treatment effectively. Treatment options include:
Psychotherapy involves talking with the therapist, who identifies and changes your unhealthy thoughts and emotions. Types include:
- Cognitive behavioural therapy is when the therapist identifies unhealthy thoughts and checks how they may be causing harmful behaviours and reactions about yourself.
- Dialectical behaviour therapy (DBT) is similar to CBT, but emphasises more on validation, or accepting uncomfortable thoughts, feelings, and behaviours, rather than fighting them.
- Psychodynamic therapy helps to cope with your daily activities.
Medications can help to change the brain chemistry that causes depression. This includes:
- Selective serotonin reuptake inhibitors (SSRIs) treat depression by increasing the availability of the neurotransmitter(chemical messengers that carry messages from one neuron to the other) serotonin in the brain.
Eg: citalopram and escitalopram - Serotonin and norepinephrine reuptake inhibitors (SNRIs) work by increasing the amount of both serotonin and norepinephrine in the brain.
Eg: duloxetine and desvenlafaxine - Tricyclic and tetracyclic antidepressants are similar to SNRIs by increasing the amount of serotonin and norepinephrine in the brain but have more side effects compared to SNRIs.
Eg: amitriptyline and doxepin - Monoamine oxidase inhibitors work by increasing the level of the neurotransmitters like norepinephrine, serotonin, dopamine, and tyramine in your brain.
Eg: isocarboxazid and phenelzine - N-methyl D-aspartate (NMDA) antagonists work by increasing levels of the neurotransmitter glutamate in the brain.
Eg: esketamine
Light therapy which includes exposure to white light helps to improve your mood and reduce symptoms of depression.
Electroconvulsive therapy (ECT) uses electrical currents to induce seizures which reduces symptoms of clinical depression.
Transcranial magnetic stimulation is done using a coil that can be placed against your scalp which will send brief magnetic impulses to stimulate the nerve cells in your brain.
Alternative therapies like meditation, acupuncture, and massage are found to be effective in reducing the symptoms of depression.
How can depression be prevented?
You cannot prevent depression, but the risk can be reduced by:
- Practising activities like exercise, yoga and meditation
- Managing stress with coping strategies
- Maintaining a proper sleep routine