What Is Unipolar Depression?
Medically reviewed by Dakari Quimby, PhD
Unipolar depression (clinical depression) is a medical term used by healthcare providers to differentiate between major depressive disorder (MDD) and bipolar disorder (BP). Unipolar depression is another name for major depressive disorder. While there is some symptom overlap between the two conditions, there are notable differences. People with unipolar depression don’t experience manic or hypomanic episodes. There are also important treatment differences.
This article will cover the key features of unipolar depression, similarities and differences between unipolar depression and bipolar depression episodes, treatment differences, and the risks of unmanaged unipolar depression. We’ll also cover what to know about recurrent and treatment-resistant unipolar depression episodes.
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Related: What Is Clinical Depression, and How Does It Feel?
Key Features of Unipolar Depression
Unipolar depression is a serious mood disorder affecting all aspects of a person’s life. It is another name for major depressive disorder. To be diagnosed with unipolar depression/major depressive disorder, a person must experience some or all of the following key features most of the day, and nearly every day, for at least two weeks:
Depressed mood
Persistent sadness or “emptiness”
Hopelessness or pessimism
Irritability, frustration, or restlessness
Feelings of guilt, worthlessness, or helplessness
Loss of interest or pleasure in hobbies and activities (anhedonia)
Fatigue or feeling sluggish and slowed down
Difficulty concentrating, remembering, or making decisions
Sleep changes, including difficulty falling asleep, staying asleep, waking up in the morning, or oversleeping
Appetite changes or unplanned weight changes
Physical symptoms including unexplained aches and pains, headaches, cramps, or digestive problems that don’t resolve with treatment attempts
Emergency Mental Healthcare
If you or someone you know is experiencing a mental health crisis, text or call 988 to reach the 988 Suicide & Crisis Lifeline. When online, visit 988lifeline.org for its chat line.
The Substance Abuse and Mental Health Services Administration (SAMHSA) can also help by calling 800-662-HELP (4357).
Related: What Is Suicide?
Type of Depression and Comorbidities
Unipolar depression is one of the most common types of depression. It has a high comorbidity rate, which means it’s common to receive a diagnosis of unipolar depression and another depressive disorder or other psychiatric illness.
Some of the most common comorbidities of unipolar depression include:
Unipolar vs. Bipolar Depression Episodes
People with unipolar depression or bipolar disorder both experience depression or depressive episodes. The most significant difference between unipolar depression and bipolar disorder is the presence or absence of mania or hypomania.
Diagnosis
To be diagnosed with bipolar disorder I, a person must have experienced at least one episode of mania in their lifetime. Mania is a mood state of extremely elevated energy, excitement, and euphoria. Bipolar II disorder diagnosis requires at least one hypomanic episode and one major depressive episode. Hypomania is a milder form of mania but can also be highly disruptive to a person’s everyday functioning.
Related: Hypomania vs. Mania: What Are the Differences?
Symptom Differences
People with bipolar disorder I are said to experience a higher number or greater frequency of depressive episodes than people with unipolar depression. They also report a lower quality of life despite receiving significantly more treatment. Compared to people with unipolar depression, people with bipolar disorder are also said to:
Experience their first depressive episode earlier in life
Have shorter depressive episodes
Present with atypical features during depressive episodes like psychotic symptoms
Additional differences include people with unipolar depression experiencing more sleep loss, anxiety, and appetite loss than people with bipolar depression.
Related: What Are Delusions?
Symptom Similarities
People living with unipolar depression and people experiencing bipolar depression episodes share similar experiences. Depression is the predominant mood state in both conditions. This can make it challenging to tell the difference between major depressive disorder and bipolar disorder.
The overlap is so strong that clinical features of depressive episodes in unipolar depression and bipolar disorder depressive episodes are identical in the Diagnostic and Statistical Manual of Mental Disorders.
Key symptom similarities include:
Feeling sad or experiencing lower than usual moods
Feeling indifferent or hopeless
Decrease in overall energy levels
Related: What Is Fatigue?
Unipolar vs. Bipolar Depression Treatment Differences
The major difference between treatment for unipolar depression and bipolar depression is the type of medication prescribed. Moderate to severe unipolar depression is treated with antidepressant medications, which are ineffective in treating depression in people with bipolar disorder. Bipolar depression is most commonly treated with mood stabilizers such as lithium.
Antidepressant medication is not recommended for people with bipolar disorder and is associated with adverse effects, including:
Worsening symptoms of depression
Agitation
Irritability
Switch into mania
Suicidal ideation
Treatment-Resistant Depression
If you’re being treated for depression and symptoms are not improving, you may have a subtype of depression known as treatment-resistant depression. People can be diagnosed with treatment-resistant depression after trying two different antidepressant medications without symptoms resolving. However, a lack of response to typical depression treatment may also be a sign of bipolar disorder. Implanting electrodes in the brain may be recommended for treatment-resistant unipolar and bipolar depression. Recurrent unipolar depression episodes increase the risk of disability, suicide, and comorbid physical health problems.
Related: How Depression Is Treated
Risks of Unmanaged Unipolar Depression
People may experience unmanaged unipolar depression if they are undiagnosed (i.e., they don’t know they have depression so they don’t seek help for their symptoms) or if they are untreated (i.e., they are not taking medication or engaging in psychobehavioral treatments like talk therapy).
Risks of undiagnosed and untreated unipolar depression include:
Developing comorbid disorders (including substance use disorders)
Worsening symptoms
Higher rates of recurrent depressive episodes
Higher rates of suicide
Related: Is Medication Adherence Important?
Recurrent Unipolar Depression Episodes
Recurrence is the return of at least five symptoms of depression and after two consecutive months without major depressive episode symptoms. People with unipolar depression may experience recurrent depression episodes for many different reasons, including genetic factors, the severity of their last depressive episode, and discontinuation of treatment.
Related: Study: There’s No Perfect Way to Wean Yourself off of Antidepressants
Summary
Both unipolar depression and bipolar disorder are characterized by depressive episodes. Someone with bipolar disorder will also experience episodes of mania or hypomania. Treatment approaches differ; unipolar depression is treated with antidepressants and bipolar depression is treated with mood stabilizers.
Living with untreated depression for any reason increases the risk of comorbid conditions, recurrent depression episodes, and suicide. People may experience recurrent depressive episodes if they have a family history of major depressive disorder, a severe previous depression episode, or if they stop treatment. Recurrent depression increases the risk of disability, suicide, and comorbid conditions.
Read the original article on Verywell Health.
