Depression And Schizophrenia: Related Disorders

Although schizophrenia and depression are classified in separate categories within the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), it isn’t uncommon for individuals with schizophrenia to also experience symptoms of depression.

The reasons why these disorders sometimes co-occur aren’t fully understood, but research is ongoing, and scientists are making progress in determining the connection between the two. Ultimately, this information might reveal more effective treatments for both disorders. Currently, a combination of therapy and doctor-prescribed medication tends to be one of the most common treatments for both depression and schizophrenia. 

Schizophrenia

Schizophrenia can be considered a somewhat uncommon mental illness, affecting roughly 0.32% of the global population. Schizophrenia is often a chronic and severe condition that typically presents in the late teens to early thirties and can be characterized by distorted thinking, hallucinations, delusions, and abnormal social behavior.

Psychotic symptoms of schizophrenia

These symptoms, also referred to as “positive” symptoms, usually distort one’s experiences, affecting how the individual thinks, acts, and perceives the world. They may be alienating and isolating as they typically disconnect one from the reality that most people share. They generally include the following:

• Delusions can be defined as irrational, illogical, false beliefs to which the individual adheres despite evidence to the contrary. People experiencing delusions might believe they’re receiving messages telepathically or from the TV or radio. The delusions could be rooted in paranoia, with the individual thinking that others want to hurt them or are “out to get” them. 
• Hallucinations generally refer to the experience of hearing or seeing things that aren’t there. People can experience other sensory hallucinations related to taste, touch, or smell, but these tend to be less common. 
• Disorganized thoughts and speech can be seen as illogical, disjointed thought patterns that typically manifest in the way one speaks. Individuals presenting this symptom might have difficulty communicating with others, or they might talk to themselves or others who aren’t there. They might jump randomly between topics, stop talking in the middle of a thought, or string together random or made-up words (sometimes referred to colloquially as “word salad”). 
• Severely disorganized behavior or catatonia can refer to abnormal, sometimes repetitive body movements. In rare cases, the individual may display catatonia that manifests as ceasing to speak or move for extended periods of time.

Negative symptoms of depression and schizophrenia

This category generally includes symptoms that directly impact mood and function, and many of these overlap with symptoms of depression. Someone with negative symptoms might experience a loss of motivation or interest and pleasure in daily activities. They may have difficulty expressing their emotions and become isolated and withdrawn from others. 

Those with negative symptoms might struggle with daily responsibilities like paying bills or caring for themselves. They may exhibit low energy, avoid activities they once enjoyed, or have no desire to engage with others in social settings.

Cognitive symptoms of schizophrenia

Cognitive symptoms typically refer to those affecting an individual’s memory, concentration, and attention. They might make it difficult to follow directions, learn new things, or remember important information. People with cognitive symptoms might have trouble using and processing information to complete tasks or make decisions. They may also have difficulty paying attention or focusing. 

Diagnostic criteria of depression and schizophrenia disorder

According to the guidelines set by the DSM-5, to receive a schizophrenia diagnosis, one must present at least one of the three primary symptoms (delusions, hallucinations, and disorganized speech) plus at least one other core symptom for a significant period over one month. If successfully treated, individuals may display symptoms for less than one month and still receive a diagnosis.

The symptoms must result in diminished function in primary areas of daily living, including work, school, interpersonal relationships, and self-care. 

Diagnostic criteria also dictate that schizoaffective, bipolar, and depressive disorders must be ruled out as potential sources of the symptoms. This generally means that there are no concurrent major depressive or manic episodes with the active-phase symptoms. If mood episodes do occur concurrently, they must appear minimally during active or residual phases. In general, the symptoms must not be related to the physiological effects of substance misuse or other medical conditions. 

Depression

Depression, also known as major depressive disorder, major depression, or clinical depression, is a common and serious mood disorder that can cause severe symptoms affecting how you feel, think, and handle daily activities. It is estimated that worldwide, roughly 5% of the adult population has depression. 

Types and symptoms of schizophrenia

There are several types of depression, some of which may come and go according to circumstances, such as seasonal affective disorder (SAD) and perinatal depression. 

Aside from major depression, persistent depressive disorder (sometimes called dysthymia) tends to be the most common type. It is usually characterized by less severe symptoms lasting for two years or longer. It may be relevant to note there is a specific form of depression (psychotic depression) that features symptoms of psychosis, like delusions and hallucinations.

Core symptoms of depression and schizophrenia usually include the following:

• Persistent sadness and/or anxiety
• Hopelessness or believing that life is meaningless
• Feelings of guilt, shame, or worthlessness without reason
• Irritability, restlessness, and frustration
• Loss of pleasure in activities one previously enjoyed
• Lack of energy, fatigue, and sluggishness
• Difficulty with memory and concentration
• Changes in sleep and appetite
• Physical discomfort like headaches, muscle aches and pains, and digestive problems
• Suicidal ideation, attempted suicide, and/or preoccupation with thoughts of death

If you are experiencing suicidal thoughts or urges, contact the National Suicide Prevention Lifeline at 988. Support is available 24/7.

Diagnostic criteria

To qualify for a diagnosis of depression, individuals must present five or more of the above symptoms, and these symptoms must cause significant distress or problems with daily function at work, school, home, in interpersonal relationships, and in other situations. The symptoms cannot result from a medical condition or the physiological effect of a substance. 

The criteria also state that the individual must never have had a manic or hypomanic episode, and the symptoms may not be better explained by schizophrenia or other psychotic disorders. 

The connection between depression and schizophrenia

Symptom similarities of schizophrenia and depression

Some of the symptoms of schizophrenia and depression are so similar that it can be possible for one disorder to be misdiagnosed as the other. These most commonly include negative symptoms of schizophrenia, such as the loss of interest in activities one used to find enjoyable or feelings of emptiness and hopelessness. Negative symptoms in schizophrenia, such as poor self-concept, shame, and self-distrust, can also be common in individuals with depression. Both disorders may involve cognitive symptoms like trouble with concentration and memory. 

Risk factors

Schizophrenia and depression might also share some of the same risk factors. For example, early trauma and neglect are frequently associated with early-onset symptoms in people with schizophrenia and depression.

Social adversity and bullying have also been suggested as potential risk factors for both schizophrenia and depression.

Genetics

Several studies have found that individuals with a family history of schizophrenia usually have an increased risk of developing depression and vice versa. This suggests that there may be shared heritable vulnerabilities between the two disorders. However, having a family history of one disorder does not guarantee the development of the other.

Studies have identified common genetic variants associated with both schizophrenia and depression. These studies have also revealed genetic overlap between the two disorders, although the specific genes and their exact roles are still being investigated.

Neurological commonalities

Dysfunction in some regions of the brain may also influence a connection between schizophrenia and depression. For example, studies indicate that individuals with schizophrenia, bipolar disorder, and major depressive disorder “share common neurobiological disruptions and neural structural distinctions between these disorders may be less prominent than initially postulated.”

Negative outcomes

Studies indicate a pattern of similar adverse outcomes associated with untreated comorbid major depression and schizophrenia. For example, substance use disorders tend to co-occur more frequently with depression and schizophrenia, as well as anxiety and personality disorders. In addition, individuals with psychotic disorders like schizophrenia and people with depressive disorders are often at greater risk for suicidal death, as are individuals with bipolar and substance use disorders.

Research on comorbid depression schizophrenia disorder

To further illustrate similarities in poorer outcomes, a 2020 study published in Biomedical Central measured the prevalence of depression among schizophrenia patients in Ethiopia. Their findings revealed that “comorbid depression was high among people with schizophrenia and associated with current substance use, suicide attempt, and long duration of the illness as well as poor quality of life.” 

Depression and schizophrenia are commonly comorbid

Online therapy can help you manage symptoms

Schizoaffective disorder

When depression and schizophrenia symptoms occur together, this is sometimes referred to as "schizoaffective disorder."  Schizoaffective disorder affects approximately 0.3% of people in the US and usually features a combination of schizophrenia, major depressive, or bipolar symptoms. There are two types classified by symptom presentation:

• Schizoaffective bipolar type is normally characterized by episodes of mania, sometimes alternating with major depression, along with positive schizophrenia symptoms.
• Schizoaffective depressive type typically involves major depressive symptoms without mania, along with positive schizophrenia symptoms.

Treatments for depression and schizophrenia

Treatment for depression and schizophrenia typically involves a combination of medication, psychotherapy, and other forms of support. Plans are usually tailored to the individual’s needs based on symptoms, medical history, and response throughout the treatment process. 

Medication and its effects on symptoms of schizophrenia

Depending on an individual’s diagnosis and symptoms, medications like antipsychotics, mood stabilizers, and antidepressants may be prescribed. Please consult your doctor or psychiatrist with any questions about medication options and speak to them before starting, stopping, or changing the way you take medication. The information in this article is not a substitute for medical advice.

Therapeutic mental health interventions for schizophrenia and depression

Also known as talk therapy, psychotherapy is often the first-line treatment for depression. While medication is usually the first-line treatment for schizophrenia, psychotherapeutic techniques can also be beneficial. Psychotherapy typically comes in several forms that aim to help individuals with mental health conditions explore the thoughts, feelings, and behaviors contributing to the condition. 

Cognitive behavioral therapy (CBT)

The most used form of treatment for both schizophrenia and depression, CBT generally focuses on identifying the thought patterns and emotions that create distress in the individual’s life. Once these are isolated, the therapist and client can work together to reframe these thoughts differently to make them more manageable and based in reality.

CBT can help individuals process and manage emotions, solve problems in daily life, and reduce stress. 

While it isn’t necessarily appropriate in every case, research indicates that internet-delivered CBT can be effective for some people with depression and schizophrenia. 

Online therapy platforms can eliminate geographical barriers to treatment, often providing a higher level of connection to a larger pool of mental health professionals experienced in treating depression and schizophrenia. Virtual therapy typically allows individuals to attend appointments from the comfort of their homes on a convenient schedule via video, phone, or online chat. 

Family education and support

Involving family members in treatment can be beneficial, as education about the illness and family therapy can help families better understand schizophrenia and learn how to provide appropriate support. 

Psychosocial programs

Programs that provide social support, vocational training, and assistance with daily living skills can help individuals with schizophrenia live more independently and improve their quality of life. Peer-to-peer counseling facilitated by someone with schizophrenia trained to support others, support groups for individuals with schizophrenia facilitated by a mental health professional, and occupational therapy designed to improve daily productivity can all serve as examples of psychosocial programs. 

It may be prudent to mention that recent reports suggest that the United States government’s National Institute of Mental Health (NIMH) has reduced its support for treatment trials for schizophrenia, bipolar, and major depressive disorder over the past few decades, potentially contributing to delays in developing newer and more effective treatments. With time and increased funding, people with schizophrenia and major depression may benefit from greater progress in treatment options.