Previously, schizophrenia was categorized into five subtypes: paranoid, catatonic, disorganized, residual, and undifferentiated [1]. In the most recent publication of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [2], these five subtypes have been removed, due to concerns relating to the validity and stability of these diagnoses [3].

As such, residual schizophrenia is no longer a specific diagnosis, but the symptoms of the five types of schizophrenia are still used by physicians to form a diagnosis, based on the nature of the presenting symptoms.

What is residual schizophrenia?

Schizophrenia can present as a variety of symptoms, including:

  • Positive symptoms:such as hallucinations, delusions, and thought disorders
  • Negative symptoms:such as social withdrawal, loss of motivation, catatonia, and blunted emotions
  • Cognitive symptoms: such as abnormal or disorganized speech and behavior, includingincoherent sentences, difficulty following a train of thought, and odd or repeated movements.

According to the DSM-IV, for a diagnosis of residual schizophrenia, there will have been at least one psychotic episode in the past, as well as a diagnosis as schizophrenia, with one or more positive symptoms present.

The person will no longer be experiencing these symptoms in as severe a manner but may continue to experience disturbances in the form of negative symptoms, such as lack of motivation or flat affect, or milder positive and cognitive symptoms, such as odd beliefs and unusual experiences [1].

Symptoms of residual schizophrenia

People with a diagnosis of residual schizophrenia will have experienced symptoms such as hallucinations, delusions, or thought disorders in the past, but these symptoms will have since reduced significantly or entirely [1].

Although psychosis will no longer be clearly present, there will still be persistent disturbances, usually in the form of negative symptoms, or milder positive symptoms [4]. Therefore, this type of schizophrenia is named ‘residual’ schizophrenia, as the most pervasive symptoms will have abated, but residual, or remaining symptoms, have continued to persist.

While this may seem to be an improvement or remission of the initial schizophrenia diagnosis, residual schizophrenia can still have a detrimental impact on quality of life, particularly in relation to social abilities [5].

Symptoms of residual schizophrenia may include:

  • Social withdrawal
  • Lack of motivation
  • Decrease in communication
  • Blunted or lack of emotions
  • Low levels of energy
  • Strange beliefs
  • Difficulties with memory or concentration
  • Some thought disorganization

Causes of residual schizophrenia

The cause of schizophrenia is not known, but may be related to several factors, such as:

Brain structure and function

Research suggests that schizophrenia may be caused by changes in neurotransmitter levels, particularly dopamine and glutamate [6].

There is also evidence to suggest that people with schizophrenia have differences in their brain structure, including a decreased amount of gray matter, suggesting that it could be caused by impaired development of the brain [7].

Similarly, traumatic brain injury could cause an onset of psychosis or schizophrenia, also suggesting that brain structure can contribute to the development of the condition [8].

Genetics

Schizophrenia is more common in those with a parent or close relative with the condition, than in those without. It is estimated that people with a parent or sibling with schizophrenia are six times more likely to develop the condition [6]. However, a family history of schizophrenia does not definitely mean that the condition will develop.

Social and environmental influences

Schizophrenia may be triggered by various social or environmental factors, such as stress, childhood trauma and abuse, social isolation, socioeconomic class, and complications during pregnancy and childbirth. These factors have been found, alone or in combination with others, to increase the risk of psychosis and schizophrenia [9][10].

Alcohol and drugs

Substance use, in particular the use of cannabis, has been found to increase the risk of psychosis. This risk is higher in those who use cannabis from a younger age, in large doses, and more frequently [10][11].

Similarly, some research suggests that cocaine, amphetamines, and alcohol can contribute to an increased risk of psychosis [10].

Treatment of residual schizophrenia

Medication

Antipsychotic medication is typically used in the treatment of all types of schizophrenia and can help alleviate most symptoms. Your doctor will initially prescribe a second-generation antipsychotic medication, such as olanzapine, aripiprazole, or risperidone. They may wish to change your dosage or medication during your treatment if your symptoms change.

People respond to medications differently, so what works for one person may not work for another. You may need to try more than one medication, or a combination of medications, before you find an effective treatment.

Antidepressants, benzodiazepines, and mood stabilizers may also be used to treat certain symptoms of schizophrenia, particularly negative symptoms such as low mood and anxiety [5].

Many antipsychotic medications can cause side effects of varying severity, which is one of the reasons that some people don’t take their medication regularly. Also, people with schizophrenia sometimes lack insight, meaning that they do not think they are unwell, so don’t think they require medication. Medication noncompliance can cause a relapse of symptoms [12].

It is important that you take your medication exactly as prescribed, as taking too much, missing doses, or suddenly stopping your medication can cause adverse effects and can worsen your condition.

Therapy

There are various types of therapy that can be useful for the treatment of schizophrenia.

Cognitive behavioral therapy (CBT) can be helpful for adapting negative thoughts and behaviors, gaining insight about your condition, and preventing relapse [5][7].

Family therapy can be useful for some people, as it can help the family to better understand and manage their loved one’s condition, symptoms, and behavior [13].

Psychosocial treatments can be especially helpful for those with residual schizophrenia compared with other types, due to the lack of pervasive positive symptoms, which allows for a greater level of engagement [5]. Psychosocial treatments can help you improve social skills, understand the importance of your medication, and find support in others who have coped with similar experiences [6].  

Self-care

  • Avoid drugs and alcohol: Drugs and alcohol can have detrimental effects on your mental health, potentially causing a relapse. They may also interact with your medication, which could cause serious side effects and risks to your physical health [9].
  • Attend all appointments: Ensure you attend all arranged appointments with your doctor, mental health nurse, and anyone else involved in your treatment, so that you continue to receive the proper care and treatment that is required for your recovery, and to ensure that they are aware of any changes or improvements in your mental and physical health.
  • Get enough sleep: Sleep is very important in improving or maintaining good physical and mental health, and a lack of sleep can contribute to a worsening of your symptoms. Try to develop a good routine for bedtime and get around 8 hours each night.
  • Be active: Do things that you enjoy, as this can help prevent symptoms from worsening. Beneficial activities include exercise, meditation, walking, reading, games, and spending time with friends.

Other types of schizophrenia

Schizophrenia is no longer diagnosed as one of five specific subtypes, but the symptoms of each subtype are still used in formulating diagnoses. Along with residual schizophrenia, the other four previously used subtypes were [1]:

Paranoid schizophrenia

According to the DSM-IV, for a diagnosis of paranoid schizophrenia, delusions and/or hallucinations must be present. The person will be very focused on at least one specific delusion, which will typically be persecutory in nature, causing a belief that someone or something will do them harm.

This could be a voice, or voices, telling them they are being followed, watched, or poisoned, or they may see or hear concerning messages. As such, people with a diagnosis of paranoid schizophrenia will typically be very suspicious and untrusting of others, which may result in expressions of anger, fear, or withdrawal.

Catatonic schizophrenia

Catatonic schizophrenia involves abnormal psychomotor function. This can be an inability to move, excessive or hyperactive moments, or odd and unusual movements or postures.

A common symptom of catatonic schizophrenia is immobility, or stupor, which means that the person appears frozen in place, sometimes for hours or days, and can be in odd positions for long periods of time [14].

Other common symptoms are echolalia and echopraxia, which respectively mean mimicking other people’s words or mimicking other people’s actions.

Disorganized schizophrenia

For a diagnosis of disorganized schizophrenia, hallucinations and delusions may be present, but the primary symptoms would be disorganized speech and behavior. This could include saying bizarre things, abruptly changing topics during conversation, repeating of words and phrases, or feeling often confused about things.

Another common symptom of disorganized schizophrenia is flat affect, meaning that the person will be expressionless and show inappropriate, or unusual responses.

Undifferentiated schizophrenia

Undifferentiated schizophrenia was diagnosed when symptoms of schizophrenia were present, but the criteria for any of the other subtypes was not clearly met.

Resources:

  1. American Psychiatric Association. (1994). Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Washington, DC: American Psychiatric Association.
  2. American Psychiatric Association. (2013, text revision 2022). Schizophrenia Spectrum and Other Psychotic Disorders. In The Diagnostic and Statistical Manual of Mental Disorders(5th ed., text rev.). APA. Retrieved from https://doi.org/10.1176/appi.books.9780890425787.x02_Schizophrenia_Spectrum
  3. American Psychiatric Association. (2013). Highlights of Changes from DSM-IV-TR to DSM-5.Psychiatry. Retrieved from https://www.psychiatry.org/File%20Library/Psychiatrists/Practice/DSM/APA_DSM_Changes_from_DSM-IV-TR_-to_DSM-5.pdf
  4. National Library of Medicine. (n.d). Residual Schizophrenia. NIH. Retrieved from https://www.ncbi.nlm.nih.gov/medgen/20665
  5. Khan, A.Y., Kalia, R., Ide, G.D., & Ghavami, M. (2017). Residual symptoms of schizophrenia: What are realistic treatment goals? Current Psychiatry, 16(3), 34-40. Retrieved from https://cdn.mdedge.com/files/s3fs-public/cp_01603034_0.pdf
  6. National Alliance on Mental Health (NAMI). Schizophrenia. NAMI. Retrieved from https://www.nami.org/About-Mental-Illness/Mental-Health-Conditions/Schizophrenia/Overview
  7. Hany, M., Rehman, B., Azhar, Y., & Chapman, J. (2022). Schizophrenia. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK539864/
  8. Molloy, C., Conroy, R.M., Cotter, D.R., & Cannon, M. (2011). Is traumatic brain injury a risk factor for schizophrenia? A meta-analysis of case-controlled population-based studies. Schizophrenia Bulletin, 37(6), 1104–1110. https://doi.org/10.1093/schbul/sbr091
  9. National Institute of Mental Health. (n.d). Schizophrenia. NIH. Retrieved from https://www.nimh.nih.gov/health/topics/schizophrenia
  10. Stilo, S.A., & Murray, R.M. (2019). Non-genetic factors in schizophrenia. Current Psychiatry Reports, 21(100). https://doi.org/10.1007/s11920-019-1091-3
  11. Marconi, A., Di Forti, M., Lewis, C.M., Murray, R.M., & Vassos, E. (2016). Meta-analysis of the association between the level of cannabis use and risk of psychosis. Schizophrenia Bulletin, 42(5), 1262–1269. https://doi.org/10.1093/schbul/sbw003
  12. Krzystanek, M., Krysta, K., & Skałacka, K. (2017). Treatment compliance in the long-term paranoid schizophrenia telemedicine study. Journal of Technology in Behavioral Science, 2, 84–87. https://doi.org/10.1007/s41347-017-0016-4
  13. Patel, K.R., Cherian, J., Gohil, K., & Atkinson, D. (2014). Schizophrenia: overview and treatment options. P & T: A Peer-Reviewed Journal for Formulary Management, 39(9), 638–645. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159061/
  14. Jain, A., & Mitra, P. (2022). Catatonic Schizophrenia. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK563222/