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Comorbidities associated with the highest COVID-19 mortality rates


According to Definitive Healthcare, providers submitted more than 1.3 million COVID-19 claims between January and September 2020. Diagnoses are primarily reported from physician groups, followed by inpatient hospitals. Understanding common COVID-19 comorbidities can help physicians provide better care to vulnerable patients.

Of the 1.3 million claims, COVID-19 was named the primary diagnosis in 316,000 – just under 24 percent. This suggests that COVID-19 was a comorbidity in about 74 percent of cases. It likely exacerbated patients’ pre-existing conditions.

The Centers for Disease Control and Prevention (CDC) began reporting excess COVID-19 deaths in March 21, 2020. Physicians report comorbid conditions when COVID-19 is the primary cause of death. 

Medical claims data is essential in finding areas with the highest diagnosis volumes of these conditions. Claims data can also help identify the physicians diagnosing and treating these patients.

Pre-existing conditions that increase COVID-19 mortality risk

The COVID-19 virus primarily impacts the respiratory system. The virus puts patients with existing respiratory issues at higher risk of complications. However, the COVID-19 virus can cause a series of associated conditions. The four major categories of COVID-19 comorbidities that lead to mortality are:

  1. Respiratory diseases
  2. Circulatory diseases
  3. Cancer
  4. Alzheimer disease and dementia

    Other common comorbidities included diabetes, renal failure, and sepsis. Pinpointing where these comorbidities are concentrated can improve population health programs. Additional precautions in these areas can also help limit the spread of COVID-19.

    Comparing excess deaths with and without COVID-19 allows providers to understand the virus’ impact. Patient deaths not reported as caused by COVID-19 could be misclassified or indirectly related. Death certificates can be submitted before the cause of death is determined. This means comprehensive information on excess mortality may not be available right away.

Direct versus indirect impact on COVID-19-related mortality

In some cases, COVID-19 may have contributed to patient death but is not listed as the cause. This misclassification could be a result of overburdened care facilities. In these cases, providers may have been unable to properly diagnose or treat COVID-19 patients. It could also be due to delays in autopsy results, leading providers to list the most likely cause of death.

Indirect COVID-19 morbidity could also stem from delayed treatment. Fear of contracting COVID-19 is causing many patients to avoid in-person care. Patients with chronic illnesses may pause treatment, which increases risk of complications. Other patients may delay seeking an initial diagnosis, making effective treatment more difficult.

Delayed treatment is especially problematic for heart attack and cancer patients. Patients experiencing heart attack symptoms may not see a doctor, leading to higher mortality rates. Postponing cancer diagnoses may also lead to more complex cases that are difficult to treat.

Increased use of telemedicine services is alleviating some of these issues. Telemedicine makes healthcare more accessible without the risk of COVID-19 exposure. Physicians can check in with patients and reduce unnecessary in-person visits. Improved access to virtual care can ensure patients with pre-existing conditions continue receiving treatment without being put at risk.

Conditions caused by COVID-19

Common symptoms of COVID-19 are well-documented. Patients often experience fever, dry cough, difficulty breathing, fatigue, and other symptoms. Many of these symptoms persist for months after patients recover.

Though the COVID-19 virus primarily impacts the lungs, it also affects the heart and the brain. COVID-19 patients often have permanent damage to their heart muscles, which can increase the risk of heart failure. Scar tissue in the lungs can lead to lasting breathing issues.

For COVID-19 patients of all ages, the virus can cause seizures and strokes. Some researchers believe COVID-19 may also increase patient risk of developing neurological conditions. This could include Parkinson’s and Alzheimer’s disease.

Access to medical claims data is essential to identify comorbidities associated with COVID-19. Understanding common comorbidities allows providers to identify the communities at the highest risk of contracting the virus. Such data can also inform population health initiatives, like drive-through testing. This will be especially important as states continue to reopen, leading to another rise in COVID-19 cases.

Coronavirus diagnoses, January-September 2020

ICD-10 codeICD-10 description# total diagnoses# principal diagnoses
B9729Other coronavirus as the cause of diseases classified elsewhere247,09549,028
B342Coronavirus infection, unspecified211,006100,261
J1281Pneumonia due to SARS-associated coronavirus89,21825,667
B9721SARS-associated coronavirus as the cause of diseases classified elsewhere60,57723,593

Fig 1. Data is from Definitive Healthcare’s Medical Claims database. Represents physician diagnosis volumes for coronavirus infections between January and September 2020. Data represented in this chart does not encompass all coronavirus diagnoses. This may be due to delays in reporting and facility partnerships with clearinghouses. Commercial claims data is from multiple claims clearinghouses in the United States. Data is updated monthly. Accessed October 2020.

Learn more

Are you looking for more information on the long-term impacts of the COVID-19 pandemic? Watch our on-demand webinar any time.

Through the Virtual Looking Glass: Examining The COVID-Driven Rise of Telehealth With Claims 

In this 15-minute webinar, two of Definitive Healthcare’s resident data analysts explore:

  • What claims data reveals about the digital expansion of healthcare
  • What these trends mean for sales organizations in companies that serve providers
  • What current regulations mean for the continued growth of digital medicine
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Definitive Healthcare

This blog was written by a former contributor at Definitive Healthcare. At Definitive Healthcare, our passion is to transform data, analytics and expertise into healthcare…

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