There are people who have significant symptoms of depression but seem to have an unimpaired level of functioning. Their struggle is more internal and not readily apparent externally. This is sometimes referred to as “high functioning” depression or persistent depressive disorder (PDD) in the DSM V. PDD was referred to dysthymic disorder in the DSM IV.
The symptoms of persistent depressive disorder are similar to those for major depression – sad or irritable mood, isolation, fatigue, hopelessness, trouble concentrating, low self-esteem, and sleep and appetite changes. The symptoms have to be present for at least 2 years and can either be subjective or observed by others. The primary difference is that these patients are able to continue function mostly normally, going to work and school, performing well, being involved in social activities, and keeping up with responsibilities at home.
There are two primary differences between PDD and Major Depression (MDD). The length of symptoms in PDD lasts longer and episodes of MDD occur over shorter periods (at least 2 weeks). People with PDD function at a fairly typical level whereas functional impairment is part of the diagnostic criteria for MDD. There are symptoms, such as suicidal ideation, that can occur in MDD, as well as associated features like psychotic features. These do not occur in PDD.
Helping patients with PDD starts with assessment and detection. It is important to assess for depressive symptoms even in patients who don’t seem to have any functional impairments, because PDD can affect a person’s ability to enjoy life. Additionally, although assessing level of impairment of depressive symptoms influences treatment considerations, it should not be the only parameter used to determine the course of treatment.
It is important to remember that “high functioning” does not mean the same thing as “fully functioning” or functioning at one’s best. So if a patient is having depressive or other mental health symptoms that are impacting their functioning in any way, it is important to further assess and consider intervention to help the patient get back to functioning at his/her best.