Distinguishing between depression and bipolar disorder

Bipolar disorder is a chronic condition that affects approximately 2% of the Australian population. It was previously known as 'manic depression' which encompassed the extreme and uncontrollable mood swings between states of manic highs and depressive lows that are experienced by those with the disorder.

Symptoms of depression and bipolar disorder

Although a component of bipolar disorder is depression, depression in itself is unipolar – meaning that there is no 'manic' part of the condition. Depression affects nearly 1 million Australians each year and is characterised by an intense and prolonged lowering of mood and sadness that may be accompanied by other physical and psychological symptoms that interfere with everyday life. For example, people with depression may lose interest or pleasure in their usual activities.

Symptoms of depression include:

• pervasive sadness
• lack of interest in activities one would usually enjoy
• extreme fatigue/loss of energy
• inability to make decisions
• sleep issues
• low self esteem
• feelings of worthlessness, hopelessness or guilt
• thoughts of death or suicide

“I was suicidal, withdrawn, isolated, hating the world, thinking everyone hated me.”

In addition to the depressive symptoms described above, people affected by bipolar disorder also experience symptoms of mania including:

• increased energy
• rapid speech and thoughts
• excessive excitement, irritability or anger
• extreme elation
• delusions of grandeur
• decreased need for sleep
• increased recklessness (may involve money, drugs, alcohol or sex)
• hallucinations/delusions

“My brain has gone at a thousand miles an hour. I’ve had periods in my life when I virtually couldn’t sleep at night...because my brain was going mad. Not mad, it was creative. Millions of thoughts, millions of ideas.”

Cause of bipolar disorder

The precise causes of bipolar disorder remain unknown, however as with other mental illnesses a family history of bipolar disorder can increase the likelihood of someone developing the condition, suggesting a genetic contribution. Environmental factors such as stressful or traumatic events may then trigger the onset of bipolar symptoms in some people.

Types of bipolar disorder

Bipolar I

To be diagnosed with Bipolar I, you need to have experienced at least one manic episode. Major depressive episodes are typical but are not required for diagnosis. Bipolar I affects both men and women equally.

Bipolar II

A Bipolar II diagnosis requires the sufferer to have experienced at least one major depressive episode, plus at least one hypomanic episode – similar to a manic episode, but less severe. Bipolar II is more common in women.

Cyclothymic Disorder

People with cyclothymic disorder experience bipolar symptoms but less severely, where episodes are less intense, shorter and less frequent.

Bipolar disorder otherwise not specified

When people experience the mood swings which indicate a bipolar disorder but don’t have episode patterns which fit into the other categories, they are classified as having a ‘bipolar disorder otherwise not specified.’ They may not meet the diagnosis criteria due to a shorter duration or lower severity of symptoms.

Distinguishing between depression and bipolar disorder

Although the cyclical nature of bipolar disorder is distinct from depression, along with the chemical profiles of the brain, clinically, the depression stage of bipolar disorder and depression itself look very similar. This can make bipolar disorder difficult to diagnose, especially if the person has experienced depressive episodes for many years without mania or hypomania symptoms. Therefore, an accurate medical history is essential in distinguishing between the two conditions. Ruth Wolever, PhD, a clinical health psychologist, research director at the Duke Center for Intergrative Medicine, and Everyday Health's Emotional Health Expert explains:

“unless the person with bipolar disorder is in a manic phase at the time he or she seeks medical help — or a hypomanic state, in the case of bipolar II — it's through the medical history that a clinician will be able to distinguish between the two mood disorders."

Treatment and support

Affective (or mood) disorders such as depression and bipolar disorder are treatable, with both psychological and medical treatments (or a combination) available to help manage and stabilise symptoms as well as help to deal with related problems.

For further information and support, visit the Beyond Blue, Black Dog Institute and SANE Australia websites.