In a recent study published in the journal JAMA Network Open, researchers assessed clinical characteristics and patterns of post-COVID-19 status (PCC) among United States veterans. Their study cohort included 388,980 veterans who were documented to experience shortness of breath, fatigue, cough, brain fog, and changes in their sense of smell and hearing. Encouragingly, vaccination was found to have a protective effect in these individuals. This study highlights the need for intensive, routine, and accurate documentation of symptoms in survivors of COVID-19 for both research and clinical care.
Study: ICD-10 Code U09.9 Documentation Rates and Clinical Characteristics of VA Patients with Post-COVID-19 Status. Image credit: Lightspring / Shutterstock
What is PCC?
Coronavirus disease 2019 (COVID-19) is estimated to have claimed more than 7 million lives and infected more than 772 million people since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic in late of 2019. In addition to the pandemic’s unprecedented socioeconomic, health, and infrastructure impacts, a growing body of evidence has identified a new condition plaguing survivors of the disease.
Colloquially called “Long COVID”, the clinically termed post-COVID-19 condition (PCC) or post-acute COVID-19 syndrome (PCAS) refers to the persistence and, in some cases, the development of new symptoms of COVID-19 long after the initial infection has passed. Both the World Health Organization (WHO) and the United States (US) Centers for Disease Control and Prevention (CDC) have defined the condition as the persistence of symptoms of COVID-19 for at least 4 weeks after discharge from usual care COVID-19.
Worryingly, these symptoms have been found to persist for months or even years after recovery from COVID-19, resulting in severe reductions in patients’ quality of life and socioeconomic loss on a global scale. Although novel and poorly understood, recent research has estimated that between 10-30% of COVID-19 survivors develop PCC, with numerical estimates of more than 65 million affected individuals.
“An International Statistical Classification of Diseases, Tenth Revision (ICD-10) code for PCC became available in the US on October 1, 2021, which provides the ability to explore correlates of clinician documentation of PCC care.”
Unfortunately, more than two years later, information about patients seeking medical treatment for PCC and documentation of care by physicians is still lacking. Understanding the patient and demographic characteristics involved in PCC care can provide insight into the mechanisms that underpin the condition and existence of multiple PCC phenotypes and more importantly, can help evolve government policy to provide better appropriate care where it is most needed.
About the study
In the present study, investigators aimed to evaluate the prevalence rates, clinical settings, risk factors, and common symptoms of long-term COVID in US military (VA) veterans with documented ICD-10 code U09.9. The study identified all VAs with positive electronic health records (EHRs) between October 1, 2021 and January 31, 2023.
Of the 411,837 individuals identified, Vas who did not visit a US Veterans Affairs center in the 18 months preceding positive COVID-19 antigen/RT0PCR tests were excluded (n = 22,857), leaving a final analytic cohort of 388,980 patients (87.3 % men). Study methodology and reporting complied with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guidelines.
Data collection included sociodemographic (age, gender, ethnicity/race), geographic (pin code of current residence), and clinical characteristics (prescription medications and records of symptoms and comorbidities) for the two years preceding initial COVID-19 infection. In addition, vaccination status (and, where applicable, the type of vaccine used) was recorded.
Of the more than 200 symptoms listed by the WHO and CDC, the researchers identified 15 predefined symptoms that are most common in PCC patients in the US through the use of the VINCI-CSDR natural language processing algorithm. To understand the development of new symptoms, 650 patients were selected and randomized to monthly follow-up (for six months) after enrollment in the study.
Statistical analyzes included calculation of Cox proportional hazards regression coefficients (hazard ratios [HRs]), adjusted for age, sex, and ethnicity/race.
Study findings
The present study revealed that the positive incidence of code U09.9 was 4.79% (at six months) and 5.28% (at twelve months after the initial diagnosis of COVID-19). Those at highest risk included elderly VAs, women, and Hispanic/Latino race/ethnicity. Infection and severity of PCC were found to be the most critical variables in VAs seeking medical help for PCC.
Encouragingly, vaccination (both primary and, to a greater extent, primary + booster) significantly reduced the severity of PCC, despite leaving the duration highly variable. Surprisingly, PCC documentation and medical care differed significantly by geographic location.
“The most common symptoms recorded in the medical record in patients with documented code U09.9 were shortness of breath, fatigue, cough, decreased cognitive function, and change in smell and/or taste.”
Of the patients selected for monthly follow-up, 64.9% developed new COVID-19 symptoms during the six months after study enrollment, highlighting that the PCC phenotype is more variable and more rapidly evolving than previously thought.
“Future studies should examine the long-term course of individuals with documented U09.9.”