While brief episodes of depersonalization or derealization can be common in the general population, the disorder is only diagnosed when these symptoms cause substantial distress or impair social, occupational, or other important areas of functioning. Signs and symptoms
The core symptoms of depersonalization-derealization disorder is the subjective experience of "unreality in ones self", or detachment from ones surroundings. People who are diagnosed with depersonalization also often experience an urge to question and think critically about the nature of reality and existence.Individuals with depersonalization describe feeling disconnected from their physicality; feeling as if they are not completely occupying their own body; feeling as if their speech or physical movements are out of their control; feeling detached from their own thoughts or emotions; and experiencing themselves and their lives from a distance. While depersonalization involves detachment from ones self, individuals with derealization feel detached from their surroundings, as if the world around them is foggy, dreamlike, or visually distorted. Individuals with the disorder commonly describe a feeling as though time is passing them by and they are not in the notion of the present. In some cases, individuals may be unable to accept their reflection as their own, or they may have out-of-body experiences. One-third to one-half of patients with DPDR also experience hearing internal voices. This is to differentiate from external voices which are more commonly found in psychosis. Additionally some individuals experience difficulty concentrating and problems with memory retrieval.
Prognosis
DPDR is typically chronic and continuous though some individuals report experiencing periods of remission. Exacerbations can be caused by psychologically stressful situations. Michal et al. (2016) analyzed a 2 case series on patients with DPDR and agreed that the condition tended to be chronic. Epidemiology
Men and women are diagnosed in equal numbers with depersonalization disorder. A 1991 study on a sample from Winnipeg, Manitoba estimated the prevalence of depersonalization disorder at 2.4% of the population. A 2008 review of several studies estimated the prevalence between 0.8% and 1.9%. This disorder is episodic in about one-third of individuals, with each episode lasting from hours to months at a time. Depersonalization can begin episodically, and later become continuous at constant or varying intensity.Onset is typically during the teenage years or early 20s, although some report being depersonalized as long as they can remember, and others report a later onset. The onset can be acute or insidious. With acute onset, some individuals remember the exact time and place of their first experience of depersonalization. This may follow a prolonged period of severe stress, a traumatic event, an episode of another mental illness, or drug use. Insidious onset may reach back as far as can be remembered, or it may begin with smaller episodes of lesser severity that become gradually stronger. Patients with drug-induced depersonalization do not appear to be a clinically separate group from those with a non-drug precipitant.