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VACO Index for calculating COVID-19 risk

March 15, 2021



In November 2020, VA researchers developed a scoring system that uses health and demographic data to accurately predict a patient’s risk of death from COVID-19. The Veterans Health Administration COVID-19 (VACO) Index has been validated as a useful tool to assess who is at the greatest risk of death from the virus.

COVID-19 is a disease caused by the SARS-CoV-2 virus, which first emerged in 2019. Symptoms include fever, cough, shortness of breath, and loss of taste or smell. Symptoms can range from mild to severe, and severe cases can lead to death.

Researchers worked with data on more than 13,000 VA patients who tested positive for COVID-19 between February and August 2020. They combined the data with patient health records and demographic information such as age, sex, and race/ethnicity to determine what factors are linked to the greatest risk of death from COVID-19.

The result was the VACO Index, which uses a checklist to give patients a score for how at-risk they are to die within 30 days of contracting the virus. Age is the strongest predictor of risk, but the index also takes into account other factors, such as pre-existing medical conditions. People with a higher risk score can be more closely monitored for the disease and advised to take extra precautions to avoid the virus. Those with a higher score are also more likely to require hospitalization if infected, meaning the index can help with care planning.

The VACO Index has been shown to be accurate both with VA and external patients. The VACO Index is an important real-time decision support tool that has the potential to allow the health care system to focus resources on those at highest risk and save lives, according to the researchers.

The Index is now available to clinicians through MDCalc, a free online medical reference for health care professionals.

Principal investigator: Dr. Amy Justice, VA Connecticut Healthcare System, Yale University

Selected publications:

Development and validation of a 30-day mortality index based on pre-existing medical administrative data from 13,323 COVID-19 patients: The Veterans Health Administration COVID-19 (VACO) Index. King JT Jr, Yoon JS, Rentsch CT, Tate JP, Park LS, Kidwai-Khan F, Skanderson M, Hauser RG, Jacobson DA, Erdos J, Cho K, Ramoni R, Gagnon DR, Justice AC. PLoS One. 2020 Nov 11;15(11):e0241825.

Risk factors for hospitalization, mechanical ventilation, or death among 10,131 US Veterans with SARS-CoV-2 infection. Ioannou GN, Locke E, Green P, Berry K, O’Hare AM, Shah JA, Crothers K, McKenna CE, Dominitz JA, Fan VS. JAMA Netw Open. 2020 Sep 1;3(9):e2022310.

Accuracy of the Veterans Health Administration COVID-19 (VACO) Index for predicting short-term mortality among 1,307 Yale New Haven Hospital inpatients and 427,224 Medicare patients. King JT Jr, Yoon JS, Bredl ZM, Habboushe JP, Walker GA, Rentsch CT, Tate JP, Kashyap NM, Hintz RC II, Chapra AP, Justice AC. medRxiv preprint.

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