Client Populations Diagnostic Criteria

Assessing and Treating Depression

This article explores what depression is, how to identify its symptoms and diagnose it in your clients, and what some of the common treatment approaches are.

By Mental Health Academy

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This article explores what depression is, how to identify its symptoms and diagnose it in your clients, and what some of the common treatment approaches are.

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Overview of depression

Depression is a common and serious mental illness characterised by persistent feelings of sadness, hopelessness, and a loss of interest in activities that a person typically enjoys. These feelings can interfere with a person’s ability to work, study, and engage in daily activities, and can lead to a variety of emotional and physical problems.

There are several types of depression, including:

  • Major depressive disorder: A severe form of depression that lasts for at least two weeks and is characterised by a number of symptoms that interfere with a person’s ability to work, study, and engage in daily activities.
  • Persistent depressive disorder: A form of depression that lasts for at least two years.
  • Substance/medication-induced depressive disorder: A prominent and persistent disturbance in mood that predominates in the clinical picture and is characterised by depressed mood or markedly diminished interest or pleasure in all, or almost all, activities.
  • Premenstrual dysphoric disorder: A form of depression that occurs when, for most menstrual cycles, a woman has at least five symptoms in the week before the onset of menses, starts to improve within a few days after the onset of menses, and experiences minimal or no symptoms in the week postmenses.

Depression can affect people of all ages and backgrounds, and it is a leading cause of disability worldwide. It is estimated that about 16.2 million adults in the United States (6.7% of the adult population) had at least one major depressive episode in 2016.

The exact cause of depression is not fully understood, but it is believed to be the result of a combination of genetic, environmental, and psychological factors. Some people may be at a higher risk of developing depression due to certain life events or experiences, such as trauma, abuse, or the loss of a loved one.

What is depression?

According to the DSM-5-TR (the latest edition of the Diagnostic and Statistical Manual of Mental Disorders), depression is defined as a mood disorder characterised by persistent feelings of sadness, hopelessness, and a loss of interest in activities that a person typically enjoys. These feelings must be present for at least two weeks and be severe enough to interfere with a person’s ability to work, study, and engage in daily activities.

In order to be diagnosed with depression, an individual must also experience at least five of the following symptoms:

  • Persistent feelings of sadness, emptiness, or hopelessness
  • Loss of interest or pleasure in activities that were once enjoyable
  • Decreased energy or fatigue
  • Difficulty concentrating, remembering, or making decisions
  • Insomnia or excessive sleeping
  • Changes in appetite or weight
  • Feelings of worthlessness or guilt
  • Thoughts of death or suicide

What are the symptoms of depression?

Depression is a mental health condition causing symptoms that we can group into physical, emotional, and behavioural categories, commonly including:

  1. For physical symptoms: Fatigue or low energy; changes in appetite and weight; sleep disturbances (insomnia or excessive sleeping); aches and pains, headaches, or digestive problems that do not improve with treatment; restlessness and agitation.
  2. For emotional symptoms: Feelings of sadness, hopelessness, or helplessness; irritability and frustration; loss of interest or pleasure in activities once enjoyed; feelings of worthlessness or guilt; difficulty concentrating or making decisions; thoughts of death or suicide.
  3. For behavioural symptoms: Withdrawal from social activities and relationships; lack of motivation or interest in daily activities; decreased physical activity or increased physical inactivity; substance abuse; poor work or school performance.

It is important to remember that depression can manifest differently in each individual and the symptoms may vary in intensity and duration. An individual experiencing symptoms of depression should seek help from a mental health professional.

How to diagnose depression

Mental health professionals can use several diagnostic tools to assess for depression. These can help a professional determine the severity of an individual’s symptoms and make a diagnosis of depression.

Some examples of diagnostic tools for depression include:

  • DSM-5-TR criteria. The DSM-5-TR is a manual used by mental health professionals to diagnose mental disorders. It provides a list of criteria that must be met in order to diagnose depression.
  • Patient Health Questionnaire (PHQ-9). The PHQ-9 is a self-report questionnaire that can be used to assess the severity of an individual’s depression symptoms. It consists of nine questions that ask about the frequency and severity of symptoms such as depressed mood, loss of interest, and changes in sleep and appetite.
  • Beck Depression Inventory, Second Edition (BDI-II). The BDI is a self-report questionnaire that consists of 21 questions that assess an individual’s symptoms of depression. It asks about symptoms such as depressed mood, loss of pleasure, and feelings of guilt.
  • Hamilton Depression Rating Scale (HDRS). The HDRS is a clinician-administered assessment tool that consists of 17 questions assessing an individual’s symptoms of depression. It asks about symptoms such as depressed mood, loss of pleasure, and changes in sleep and appetite.
  • International Classification of Diseases (ICD-11). The ICD is a standardised system for classifying and coding diseases and related health conditions. It is published by the World Health Organisation (WHO) and is used in many countries around the world as a standard diagnostic tool for epidemiology, health management, and clinical purposes. The ICD-11 includes codes for a variety of mental disorders, including depression. Mental health professionals can use the ICD-11 codes to diagnose and classify depression and other mental disorders. The ICD codes can be used to identify patterns and trends in mental health conditions, and to develop treatment and prevention strategies.

Common treatment approaches for depression

Several different treatment approaches are commonly used to help individuals manage depression. These may include:

  • Medication. Antidepressant medications, such as selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and monoamine oxidase inhibitors (MAOIs), can be effective in reducing symptoms of depression.
  • Psychotherapy. Different types of psychotherapy that may be used to treat depression include cognitive-behavioural therapy (CBT), interpersonal therapy (IPT), and dialectical behaviour therapy (DBT).
  • Mindfulness and relaxation techniques. Practices such as mindfulness meditation, progressive muscle relaxation, and deep breathing can help individuals with depression reduce stress and improve their overall well-being.
  • Lifestyle changes. Making changes to one’s diet, exercise routine, and sleep habits can be helpful in managing symptoms of depression.
  • Transcranial magnetic stimulation (TMS). TMS is a non-invasive treatment that uses magnetic fields to stimulate specific areas of the brain. It is typically used for individuals with depression who have not responded to other treatment approaches.
  • Alternative treatments. Some individuals with depression may find relief with alternative treatments such as herbal supplements, acupuncture, or light therapy.

It is important to note that treatment for depression often involves a combination of approaches, and the most effective treatment will vary from person to person. A mental health professional can help an individual develop a treatment plan that is tailored to their specific needs and goals.

Key takeaways

  • Depression is a common and serious mental illness characterised by persistent feelings of sadness, hopelessness, and a loss of interest in activities.
  • Depression can affect people of all ages and backgrounds, and it is a leading cause of disability worldwide.
  • Symptoms of depression can be grouped into physical, emotional, and behavioural categories.
  • Mental health professionals can use several different diagnostic tools to assess for depression.
  • Common treatment approaches for depression include medication, psychotherapy, mindfulness and relaxation techniques, lifestyle changes, transcranial magnetic stimulation, and alternative treatments.

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