Comorbidities are 2 or more medical conditions that occur at the same time. Often, 1 exists before the others occur. However, they can be diagnosed at the same time.1,2
Comorbidities are different from complications. A complication is a problem that develops as a result of a health condition or its treatment. An example would be a drug side effect. Sometimes, complications can lead to combordities.1,2
What causes comorbidities?
Comorbidities, or comorbid conditions, may occur together because they share the same risk factors or underlying causes. Or, a complication of one condition may increase the risk of developing a comorbid condition.1,3,4
antipsychotic drugs is metabolic syndrome. This term refers to changes in the way your body processes fats, sugars, and other hormones. Metabolic syndrome is a possible complication of schizophrenia treatment. And metabolic syndrome increases the risk of developing diabetes or heart disease.1,3,4
If a person with schizophrenia develops metabolic syndrome that then leads to diabetes, diabetes is a comorbid condition of schizophrenia for them.1,3,4
Several health conditions that commonly co-occur with schizophrenia are below. But this is not a full list of all potential comorbidities. Talk with your doctor about issues you are at risk for. They will monitor and treat each condition differently.
Other mental health diagnoses
It is common for people with schizophrenia to have a co-occurring mental health condition. For example, the chance that a person with schizophrenia will also have depression may be as high as 50 to 75 percent.5
The most common mental health conditions that occur alongside schizophrenia include:4-7
- Depression
- Anxiety
- Obsessive compulsive disorder (OCD)
- Post-traumatic stress disorder (PTSD)
- Eating disorders
- Bipolar disorder
The term “schizophrenia” actually refers to a spectrum of disorders. Some of these conditions have a mix of schizophrenia symptoms and mood disorder symptoms. One example is schizoaffective disorder.4
A person with schizoaffective disorder has schizophrenia as their primary issue. But they also have periods of mood disorder symptoms. This mood disorder could be major depressive disorder or bipolar disorder.4
Substance use disorder
If a person has schizophrenia, they have a higher risk of developing problems with substance use, too. This may be due to shared risk factors, like severe stress or genetic causes. It may also be due to the specific processes in the brain. For example, some of the areas of the brain affected by schizophrenia may also play a role in the desire to use drugs or alcohol.4,8
A substance use disorder can center around alcohol, tobacco, marijuana, opioids, and other substances. Sometimes, multiple substances can be involved at the same time. As with schizophrenia, doctors use the DSM-5 to diagnose substance use disorder. Its criteria for substance use disorder includes:8,9
- Continuing to use substances even when it causes problems in relationships
- Needing more of a substance to get the same effect
- Not carrying out daily tasks or work due to substance use
If substance use is affecting your or a loved one’s daily life, talk with your doctor. They may be able to recommend options that can help. You also can call the Substance Abuse and Mental Health Services Administration (SAMHSA) hotline at any time. They can be reached at 1-800-662-HELP (1-800-662-4357). Or you can text your zip code to 435748 (HELP4U) for resources in your area.10
Diabetes
People with schizophrenia are at an increased risk for developing type 2 diabetes. This may be due to drug side effects like metabolic syndrome. But some people have diabetes before schizophrenia symptoms start. This could point toward both conditions having similar risk factors.4,11
For example, both schizophrenia and diabetes could share similar genetic causes. Or certain behaviors could lead to both schizophrenia and diabetes. These behaviors could include smoking, eating a poor diet, and not getting enough physical activity.4,11
However, the relationship between diabetes and schizophrenia is still unclear. More research is needed to understand if there is a link between the 2.
Cardiovascular disease
Metabolic syndrome also changes the way the body processes fats. This can lead to higher amounts of fat, including cholesterol, in the blood. This buildup of cholesterol can lead to high blood pressure, heart attacks, heart disease, and stroke. These are all considered cardiovascular conditions.11-13
Like diabetes, these conditions may also be caused by shared risk factors. Factors may include genetics, substance use, and lifestyle choices.11-13
Neurological conditions
Schizophrenia affects the brain and way a person thinks. This has made some researchers wonder whether schizophrenia increases the risk of other neurological conditions. One neurological issue studied alongside schizophrenia is dementia (a loss of mental functions). Current research suggests that people with schizophrenia are at higher risk for developing dementia than people without it.14,15
Other neurological issues that have been studied with schizophrenia include sleep disorders. People with schizophrenia appear to have an increased risk of developing sleep apnea and other sleep-related health conditions.4
Sexually transmitted infections (STIs)
Schizophrenia may lead some people to practice risky sexual behaviors. This includes having sex without a condom. Substance use, homelessness, and psychosis all can increase the chance that someone will have unprotected sex. People with schizophrenia commonly experience all 3 of these factors.16
Sex without a physical barrier like a condom can lead to sexually transmitted infections (STIs). STIs include chlamydia, gonorrhea, HIV, syphilis, and others.16
If you are concerned about your STI risk, get tested early and often. You can ask your doctor for testing locations near you. The Centers for Disease Control and Prevention also has an online testing locator. Typing in your zip code or city will pull up fast, confidential, and free testing locations in your area.17