COVID-19 as Principal Diagnosis, Comorbid, or Incidental Condition

Clinical documentation integrity (CDI) is more important than ever, in the age of COVID-19.

I have been hearing grumbles on TV and in social media that the diagnosis of COVID-19 in some patients who are being counted as COVID-19 patients overwhelming the nation’s hospital systems is not really legitimate.

The implication is that unless the condition is the principal diagnosis, it shouldn’t count. Really? Is it a phantom PCR test, pretend personal protective equipment, fake ventilation needs in an isolation room on a COVID-19 ward? Does the room turnover not require the same time-consuming terminal cleaning? Do precautions not need to be taken to prevent those patients from spreading virus to other patients?

If it is a secondary diagnosis, is it truly incidental (e.g., not impacting the patient at all, like they are asymptomatic), or is it causing the admission secondhandedly? How can we tell?!

Clinical documentation integrity (CDI) is more important than ever, in the age of COVID-19. It is critical that we ensure that providers are documenting accurately, and that coders are picking up the right codes in the correct sequence.

There are actually five buckets of COVID-19-related patients in our hospitals now. There are patients admitted:

  1. With acute or persistently symptomatic COVID-19 infections with potentially life-threatening manifestations like COVID-19 pneumonia or acute respiratory distress syndrome (ARDS). The principal diagnosis is U07.1, COVID-19 plus the manifestation, Present on Admission-Yes (POA-Y);
  2. For an underlying condition that was exacerbated or caused by contracting COVID-19. Think severe exacerbation of chronic obstructive pulmonary disease (COPD) or heart failure compounded by the hypoxemia of COVID-19. U07.1 is a secondary diagnosis and a major comorbid condition or complication (MCC);
  3. For a totally unrelated condition, who happen to also have a COVID-19 infection POA-Y. An example would be a motor vehicle collision patient with a fractured femur whose admission PCR is positive. These cases are truly incidental;
  4. For a condition for which COVID-19 is believed to be responsible, but U07.1 has resolved. For instance, a patient who has a pulmonary embolism, renal failure, or organizing pneumonia, but no longer has active, acute COVID-19. These patients have a secondary diagnosis of U09.9, Post COVID-19 condition, unspecified. They do not have U07.1; and
  5. With some other condition who contract COVID-19 as a nosocomial infection. They also get U07.1 as a code, but it is a secondary condition and POA-N.

Coders need to remember that uncertain diagnoses of COVID-19 are not coded as U07.1. Everyone else needs to remember that coders are permitted to assign U07.1 if a positive COVID-19 test result has been obtained, even if no one documented it.

Are the statistics correct? I am seeing quoted 40-percent “incidental” COVID. Is the sequencing accurate? Are the POA indicators correct? Is it really incidental?

The most important relevant Official Guideline is I. C. 1. g. 1) (b) Sequencing of codes (of COVID-19). The first part of the first sentence says, “when COVID-19 meets the definition of principal diagnosis.” This invokes Section II, which deals with the selection of principal diagnosis (PDx), as long as the Tabular List and Alphabetic List don’t contradict the guidelines. People are misinterpreting the guidelines and placing undue emphasis on the second phrase, which continues, “U07.1, COVID-19 should be sequenced first.”

When does a condition meet the definition of PDx? The PDx is the “condition which is established, after study, to be chiefly responsible for occasioning the admission of the patient to the hospital for care.” It is present on admission. It typically consumes the lion’s share of the resources. The only bucket above that meets these criteria is Bucket No. 1. Only in active infections is U07.1 PDx.

The Guidelines overtly advise following sepsis guidelines if COVID-19 has progressed to sepsis. If the patient is obstetric or neonatal, those guidelines take precedence. If there is a lung transplant recipient with COVID-19 pneumonia, the T86 code indicating infection of lung transplant would be PDx.

There are two small wrinkles relative to this issue. The first is the 20-percent increase in the Medicare Severity DRG, which is applied if there is a positive COVID-19 laboratory test. Some people may think that incidental COVID-19 is not entitled to the upward adjustment. There are precautions and actions taken just on the basis of being infected with SARS-CoV-2 that justify this adjustment. I cannot imagine a situation currently, during the Omicron/Delta surge, which would negate COVID-19 meeting legitimate secondary diagnosis criteria.

The second issue is the sequencing instruction by the Health Resources & Services Administration (HRSA) for eligibility for the COVID-19 Uninsured Program. Patients who are uninsured are covered by the American Rescue Plan Act of 2021 through the Provider Relief Fund. The guidance by HRSA for claims reimbursement submission is that U07.1 must be listed as the primary diagnosis. Paraphrased, HRSA recognizes that using COVID-19 as primary diagnosis is contrary to the Official Coding Guidelines; however, HRSA’s COVID-19 Uninsured Program is not a health plan, so it is not subject to HIPAA requirements.

Does this make it look like the healthcare establishment is gaming the system? The government makes the rules; hospitals are just trying to follow them to get paid appropriately.

Nosocomial COVID-19 could be ascertained by analyzing the POA indicator. That might be an important quality measure to determine and monitor.

How could we tease out incidental from an additional compounding diagnosis? Without chart review, I would recommend compiling a list of diagnoses that could probably be exacerbated or initiated by the presence of a COVID-19 infection. They are likely to be cardiac or pulmonary in etiology, but not exclusively. If one of those (e.g., exacerbation of COPD, acute on chronic heart failure) is PDx and COVID-19 is a secondary diagnosis, the virus is a comorbidity, not incidental. Incidental COVID-19 is also likely to be asymptomatic or minimally symptomatic, as opposed to having genuine manifestations.

This will miss some cases. For instance, say an elderly patient who has COVID-19 and has been weak gets dehydrated and falls, fracturing his hip. Is his hip fracture sequenced PDx to correspond with the principal procedure, or is his PDx COVID-19 because it is the reason for occasioning the admission?

Does it really matter? The public isn’t likely to be savvy enough to understand the nuanced difference between comorbid and incidental if they can’t comprehend that an mRNA vaccine doesn’t alter a person’s DNA. Hospitals are busting at the seams with COVID-19 patients, patients with something else caused by COVID-19, patients with something else who just happen to be COVID-19-positive, and a couple of patients who don’t have COVID-19, now or yet.

An absurdly high positivity rate indicates there is a variant of crazy transmissibility that is ravaging our population. Incidental, schmincidental; isn’t that bad enough?!

Programming Note: Listen to Dr. Erica Remer today as she co-hosts Talk Ten Tuesdays with Chuck Buck at 10 am Eastern.

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Erica Remer, MD, FACEP, CCDS, ACPA-C

Erica Remer, MD, FACEP, CCDS, ACPA-C has a unique perspective as a practicing emergency physician for 25 years, with extensive coding, CDI, and ICD-10 expertise. As physician advisor for University Hospitals Health System in Cleveland, Ohio for four years, she trained 2,700 providers in ICD-10, closed hundreds of queries, fought numerous DRG clinical determination and medical necessity denials, and educated CDI specialists and healthcare providers with engaging, case-based presentations. She transitioned to independent consulting in July 2016. Dr. Remer is a member of the ICD10monitor editorial board and is the co-host on the popular Talk Ten Tuesdays weekly, live Internet radio broadcasts.

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