Nineteen Percent of Asymptomatic COVID-19 Patients Develop Long-Haul COVID

Nineteen percent of COVID-19 patients without symptoms went on to exhibit at least one of the post-COVID conditions known as long-haul COVID 30 days or more after their initial COVID-19 diagnosis.This is among the findings in FAIR Health's new white paper, the eighth of its COVID-19 studies, A Detailed Study of Patients with Long-Haul COVID: An Analysis of Private Healthcare Claims. The report uses FAIR Health's repository of private healthcare claims data to study 1,959,982 COVID-19 patients—the largest population of COVID-19 patients ever studied for long-haul COVID—over the period from February 2020 to February 2021.

Although many patients recover from COVID-19 within a few weeks, some exhibit persistent or new symptoms more than four weeks after first being diagnosed. Names for such post-COVID conditions include not only long-haul COVID but long COVID, post-COVID syndrome or post-acute sequelae of COVID-19 or of SARS-CoV-2 (PASC).

Findings about long-haul COVID reported in FAIR Health's white paper include:

• The five most common post-COVID conditions across all ages, in order from most to least common, were pain, breathing difficulties, hyperlipidemia, malaise and fatigue, and hypertension.

• The odds of death 30 days or more after initial diagnosis with COVID-19 were 46 times higher for patients who were hospitalized with COVID-19 and discharged than patients who had not been hospitalized. Of COVID-19 patients who were hospitalized and discharged, 0.5 percent died 30 days or more after their initial diagnosis.

• Among COVID-19 patients with preexisting conditions, intellectual disabilities were associated with the highest odds of death 30 days or more after initial COVID-19 diagnosis.

• In addition to asymptomatic patients, those presenting with post-COVID conditions included 27.5 percent of COVID-19 patients who were symptomatic but not hospitalized, 50 percent of hospitalized patients and 23.2 percent of all patients who had COVID-19.

• The ranking of the most common post-COVID conditions varied by age group. For example, in the pediatric population (0-18), pain and breathing difficulties were the top two conditions, as in the all-ages cohort, but intestinal issues, rather than hyperlipidemia, were the third most common.

• Most of the post-COVID conditions that were evaluated were associated more with females than males. In the case of 12 conditions, however, males more commonly had the condition diagnosed than females. For example, of patients who had post-COVID cardiac inflammation, 52 percent were male and 48 percent female. By age, the largest share (25.4 percent) with this cardiac condition was found in a young cohort—individuals aged 19-29.

• Of the four mental health conditions evaluated as post-COVID conditions, anxiety was associated with the highest percentage of patients after COVID-19 in all age groups. Depression was second, adjustment disorders third and tic disorders fourth.

FAIR Health President Robin Gelburd stated: "Even as the COVID-19 pandemic wanes, long-haul COVID persists as a public health issue affecting many Americans. The findings in our new study shed significant light on this emerging issue for all individuals who have long-haul COVID, as well as for policy makers, providers, payors and researchers."

This is the eighth in a series of studies released by FAIR Health on the COVID-19 pandemic. The first study examined projected US costs for COVID-19 patients requiring inpatient stays, the second the impact of the pandemic on hospitals and health systems, the third the impact on healthcare professionals, the fourth key characteristics of COVID-19 patients, the fifth the impact on the dental industry, the sixth risk factors for COVID-19 mortality and the seventh the impact on pediatric mental health.