You may come across the word “comorbidity” when searching the internet for information about a medical condition or when talking with your doctor.

Like many medical terms, the word “comorbidity” can be simplified. It means a coexisting health condition. For example, if you have diabetes and high blood pressure, these two conditions are comorbidities for each other.

Understanding whether you have comorbidities helps doctors develop the best treatment plan for your health condition.

In this article, we break down what you need to know about this common medical term.

A comorbidity is any coexisting health condition. The prefix “co” means together and the word “morbidity” is the medical term for a health condition. It can also be described as cooccurring or coexisting conditions.

Comorbidities sometimes interact with each other, but they can also exist entirely separately. Some conditions may raise your risk of developing others, or may commonly occur together. For example, a heart attack often occurs with stroke or vascular disease. Chronic kidney disease may occur with hypertension and anemia.

Comorbidities are often chronic conditions and can include physical or mental health.

It’s possible to have many comorbidities at the same time. For example, a person could have depression, arthritis, diabetes, and high blood pressure.

Sometimes, the term “multimorbidity” is used interchangeably with “comorbidity” if more than two health conditions are present. But the term “comorbidity” is generally used when one particular condition is the focus.

Comorbidities are coexisting conditions that develop independently of each other. They may share the same risk factors, but they don’t directly cause each other. For example, obesity may increase your risk of developing the comorbidities arthritis and diabetes.

A complication is a medical condition that develops from another health condition or from treatment for another condition. For example, HIV retinopathy is a complication of untreated HIV.

Some comorbidities occur together randomly, but others are connected through shared genetic, behavioral, or environmental factors.

Comorbidities can be linked through:

  • chance occurrence between two conditions
  • overlapping risk factors
  • one condition results from complications of the other
  • a third condition causes both conditions

Comorbidities are often long-term conditions. Some of these conditions are very common. For example, about 22.7 percent of adults in the United States have arthritis.

Many adults have at least one chronic condition. The World Health Organization estimates that 87 percent of deaths in high income countries are due to chronic conditions.

Common comorbidities include:

Anybody can develop a comorbidity, but certain groups of people may be at a higher risk for health conditions than others.

Comorbidities become more common with age because older adults are more likely to have health conditions than younger adults. Increasing age is the main risk factor in high income countries.

People with less access to healthcare are also at risk. A 2017 study found that the presence of comorbidities is higher in lower socioeconomic groups.

Other at-risk groups include pregnant women and people with congenital or early life diseases.

Certain lifestyle habits can also increase your risk of developing certain conditions. For example, smoking is linked to a number of health conditions that include:

Having comorbidities can complicate treatment for a health condition. For example, people with substance use disorder and a mental health comorbidity are at a higher risk of treatment dropout than people without mental illness.

In the United Kingdom, 1 in 3 adults admitted to the hospital have five or more comorbidities.

Having two or more comorbidities is associated with:

  • reduced quality of life
  • impaired function
  • worse physical and mental health
  • increased death

Treating comorbid conditions usually involves contacting separate specialists to develop a treatment plan for each condition. Current healthcare models are single disease-orientated and often cause challenges for people with multiple chronic conditions.

Different conditions may require separate medications, which can cause additional problems. Some medications might not be safe to take together, or one might lower the effectiveness of another. One 2021 research review in England found that taking five or more medications was associated with a 21 percent increased rate of falls in older adults over a 2-year period.

The presence of some morbidities can complicate surgery as well. In a 2018 study, researchers found that the comorbidities associated with the highest deaths during surgery were liver disease, electrolyte disorders, and coagulopathy, an impairment in blood clotting.

Tips for managing comorbidities

Managing multiple chronic conditions can be challenging. Here are some tips that may make the process easier:

  • Tell your doctors about any health conditions you have so they can consider these when developing your treatment plan.
  • Communicate with your specialists that you have other health concerns and indicate if you’re taking other medications.
  • Bring your medications with you to all your medical appointments.
  • If time is limited at an appointment, tell your doctor about what health issue is bothering you the most.
  • Coordinate your healthcare with a primary doctor who can help you make sure your treatment program fits together.
  • Try to incorporate good lifestyle habits into your life like quitting smoking, exercising regularly, and eating a balanced diet.
  • Take all your medications as prescribed.
Was this helpful?

Comorbidities are coexisting health conditions that are often chronic. They can be related to each other or occur independently.

It can be difficult living with multiple chronic conditions, but you can work with your doctor to develop a treatment plan that addresses all your health needs.

Your doctor may refer you to multiple specialists to treat each condition. It’s important to communicate with each specialist about any other conditions that may affect your treatment. Your primary doctor can help you coordinate your treatment plan.