Comorbidity in Biology and Medicine

In medical terminology, comorbidity is a condition or a disease that co-exists with another condition or disease in the body. However, it is independent of the other disease or condition. Comorbidity can also be termed as a secondary diagnosis that is recognized:

• During or after the treatment for the principal diagnosis is going on

• The detection of a condition that warrants a visit to a physician

• At the time of hospital admission or rehabilitation. 

Although comorbidity is discovered at the time during or after the principal diagnosis, the condition has been present in the body for some time before the diagnosis. Comorbidity examples include heart disease, cerebrovascular disease, sensory impairment, respiratory disease, diabetes, joint disease, high blood pressure (hypertension), any kind of substance abuse or psychiatric disorders (including dementia, eating disorders, and anxiety disorders).

Comorbidity is different from mortality or death rate and in medical terms as well in case of health insurance matters, comorbidity meaning is the presence of other illness in the body. A person having comorbidity requires an increased level of health care and this tends to increase the cost of health care sometimes. At the same time, it decreases the person’s capability to function properly in the day to day life. The severity of the comorbidity can affect the person’s responsiveness to the treatment of the principal diagnosis. Comorbidities can now be easily detected with improved and advanced ways of diagnosis. They are found more often in an aging population. 

A good example can be the responsiveness to COVID-19 treatment in comorbid patients. A patient without comorbidity responds well to the COVID-19 treatment compared to a person with a pre-existing condition or comorbidity like diabetes. 

Another example can be of a rehabilitative patient with congestive heart failure as comorbidity. If the co morbidity is mild it will not affect the patient’s activity level or care but if it is severe, the patient may feel weak, making the process of rehabilitation complicated, and raising the cost of care.

History of Comorbidity

The term was coined first in the 1970s by A.R. Feinstein, who was an American doctor, an epidemiologist. Feinstein used the example of people suffering from rheumatic fever also usually suffering from multiple other diseases to demonstrate comorbid conditions meaning. Since then, comorbidity meaning is the presence of more than one mental or physical illness in the same person.

Treatment in Case of Comorbidity

When there is an overlap of medical conditions it is a challenge for the health care professionals to do an accurate principal diagnosis and to chart the treatment course for the patient. It also increases the cost of treatment for the patient.

For example, a person diagnosed with COVID-19 who also has diabetes needs to be treated for both conditions, but there may be an overlap between the symptoms and medications for both conditions. There needs to be coordination between the various health care professionals providing treatment to the patient.

If a person has more than one medical condition or disorder, it is important that the doctor is made aware of all medications being taken by the person to eliminate the risk of any medication complications like allergies or overdose of the same medicine. 

Coronavirus and Comorbidity

Around the globe, doctors have shared their findings of the correlation between comorbidity and its effect on patients contracting coronavirus. Approximately 48% of the fatalities resulting from coronavirus were people who had underlying comorbidities. Out of this 48%, more than 30% percent were suffering from Hypertension, 19% percent diagnosed with diabetes, and around 8 % had cardiovascular conditions.

Although detailed studies are ongoing and comprehensive research analysis is yet to come, it can be broadly concluded that diabetes, hypertension, and cardiovascular diseases are some comorbidities that can accelerate the rate at which the body gets affected by the Coronavirus. It has also been seen that comorbidities can hamper faster recovery.

People with a weak immune system are prone to contracting coronavirus. According to recent studies, people with comorbidities have a higher mortality rate than people with no comorbidities. 

• Hypertension: 

Hypertension, as comorbidity, affected the response of a coronavirus affected patient towards a full and speedy recovery. It lowers immunity significantly, making it easier for the virus to affect the person.

• Diabetes: 

Poor glycemic levels affects the body’s capability to fight off infections to a great extent. It also leads to the onset of secondary bacterial infections in the abdomen and lungs.

• Cardiovascular Diseases: 

Patients with cardiovascular comorbidities can experience myocardial damage and cardiovascular collapse when affected by the coronavirus.

What is the Comorbidity Cause?

There are some comorbidities that occur randomly in people. An example of this would be the seasonal allergies in people or arthritis. Then there is the non-random comorbidity which can be brought about by three broad processes:

• One Disorder Causing Another: 

In this case, one disorder directly causes the onset of the second disorder. For example, persistent substance or alcohol abuse can lead to liver cirrhosis.

• Effects of One Disorder Causing Another: 

In this case, the side effects or indirect effects of one disorder cause the onset of the second disorder. For example, a patient diagnosed with a heart disorder may experience stress and make certain changes in the lifestyle. This can induce anxiety which becomes the second disorder.

• Common Causes: 

Traumatic life events, leading to mood disorders, depression or comorbid anxiety are common comorbidity triggers. Sometimes, biological factors and common genetic factors play a critical role in causing strong comorbidities among people suffering from commonly occurring mental disorders.