Differentiating Between GAD and Depression

Understanding the difference between Generalized Anxiety Disorder (GAD) and a major depressive episode (or Major Depressive Disorder) can be fairly difficult. The following will describe how they are different as well as some areas of overlap, and will provide a framework to better understand the unique features of GAD.

Symptoms of Depression
First, a complete breakdown of GAD symptoms can be found here. For a major depressive episode to be diagnosed, a person must have five or more of the following symptoms over at least two weeks that is a change from typical functioning:

1. Depressed mood for a significant portion of the day, everyday
2. Loss of interest in activities
3. Significant weight change
4. Increased or decreased sleep
5. Noticeable psychomotor agitation or retardation, such as appearing restless or slowed down
6. Experiencing low energy or fatigue most days
7. Feelings of intense guilt or worthlessness
8. Difficulty concentrating or making decisions
9. Increased thoughts of suicide or death

Differences
First, The largest distinction is that depression is classified as a mood disorder whereas GAD is classified as an anxiety disorder, which means there are key differences at a basic level. Specifically, depression represents a decrease in interest in activities (and sometimes life itself) and experience of depressed mood, whereas GAD represents difficult to control worry and fear. Furthermore, individuals with depression often feel sluggish and lethargic with a slowed pace of thoughts, whereas those with GAD often feel keyed-up and nervous and experience a faster pace of thoughts.

Similarities
Beyond the hallmark differences, there are some ways that the disorders are similar. Most notably, people experiencing either disorder can have sleep disturbance such as insomnia, as well as difficulty concentrating, making decisions, and focusing attention. There are also some similarities in how the disorders can develop, with family history (genetic influence) and experiencing stressful life events being chief causes for both.

Conclusion
Although there are some shared symptoms and causes, the disorders are actually quite different. Mental health professionals generally can notice the difference very quickly, even just talking with someone for several minutes. Being able to tap into the core emotions you have can be the best evidence for which you may be experiencing. Furthermore, it is important to note that some people with depression also experience anxiety, and that one can have both disorders, although it is not especially common.

Source: American Psychiatric Association (2000). Diagnostic and Statistical Manual of Mental Disorders (4th Ed., Text Revision). Washington DC: American Psychiatric Association.