People Hospitalized for COVID More Likely to Develop Long-term Conditions

A new study shows that hospitalized patients who tested positive for COVID-19 were more likely to experience shortness of breath, fatigue, and type 2 diabetes after contracting the virus.

In the study published in JAMA Network Open, researchers analyzed aggregated electronic health record data of more than two million children and adults who were tested for COVID-19 between March to December 2020 and had a subsequent medical encounter 31 to 150 days afterward. 

They found that the prevalence of diagnoses of new symptoms and conditions largely varied depending on COVID-19 test results, age, and whether a patient was hospitalized after testing positive for COVID-19.

The findings of the study can inform healthcare professionals about the symptoms and conditions that can develop after infection and help guide long COVID research.

Long COVID Symptoms

When it comes to post-COVID conditions, researchers initially began understanding the phenomenon through anecdotal reports, which made it difficult to study because the problem was yet to be defined. 

“It could have been one syndrome, or it could have been multiple syndromes,” Brian Labus, PhD, MPH, REHS, assistant professor in the department of epidemiology and biostatistics at the University of Nevada, Las Vegas, told Verywell.

“Different people may have different problems at different ages, so we have to fully describe what is going by disease, age, sex, etc.,” Labus added. “The better we can describe the disease, the better we can study it, and hopefully, find ways to prevent and treat it. This study helps us understand what we mean by long COVID better.”

The researchers found that shortness of breath and fatigue were the most prevalent symptoms for people who tested positive for COVID-19 from both age groups. However, changes in bowel habits were more common among individuals younger than 20 years old, while sleep disorders are more common among those who are 20 years old and older.

Among all the patients who were hospitalized, nonspecific heart rate abnormalities—such as tachycardia, bradycardia, or palpitations—were also common.

The study also observed the most prevalent conditions that occurred 31 to 150 days following the COVID-19 test. For patients 20 years old and older who were hospitalized after testing positive, the following conditions were the most prevalent:

• Type 2 diabetes
• Anxiety and depression
• Ataxia or trouble walking

Among the patients from this age group who were ventilated, new-onset peripheral nerve disorders and myoneural disorders were also common. Meanwhile, for hospitalized patients below 20 years old, anxiety and depression were the most prevalent new conditions.

“The very large number of individuals in this study allowed the authors to subdivide the risk of certain conditions related to the severity of disease and age,” Vincent Hsu, MD, executive director of infection control at AdventHealth, told Verywell. “This is important as both healthcare providers and patients will use these data to help predict or anticipate these new symptoms, which are distributed differently based on age group and disease severity.”

Long-term Symptoms Linked to COVID-19 Severity

The study’s findings also suggest that long-term symptoms and conditions can be more common for those with increased COVID-19 severity. The researchers observed an increase in symptoms and conditions among those who were hospitalized and/or ventilated compared to those who weren’t.

Like many viral diseases, COVID-19 causes inflammation in various organ systems. The more severe or widespread the inflammatory response, the greater the disease severity, Hsu said.

“This inflammatory response may then manifest itself in other organ systems in the form of symptoms at a later date or not recognized until later, although there may be other mechanisms that are yet to be identified,” he added.

There are other proposed mechanisms that could predict long COVID, such as having a higher viral load during the early phases of COVID-19 or a stronger dysregulated immune response in the immediate post-acute phase of the disease, Anish Mehta, MD, MPP, medical director of care transformation at Eden Health, told Verywell.

“This study demonstrates another way in which the virus that causes COVID-19 is more severe than other viruses,” he added. “It’s also important because it helps medical professionals know what type of symptoms and conditions to look out for after someone has had COVID-19 so they can help counsel patients on what to expect.”

Susceptibility to Breakthrough Infections

Patients with long COVID are also vulnerable to COVID-19 reinfection. However, we need further research to determine whether they are more susceptible to it.

“There are some studies showing that patients with certain long COVID symptoms have lower levels of COVID-19 antibodies, but whether that means they’re more susceptible to reinfection is unclear,” Mehta said. “However, we do know COVID-19 vaccinations are associated with reduced long COVID incidence if someone gets a breakthrough infection.”

A recent study that investigated four potential risk factors for long COVID found that the presence of certain autoantibodies may be linked to a higher likelihood of lingering symptoms. They found that as autoantibodies increase, protective COVID-19 antibodies decrease, which can make people with long COVID more susceptible to breakthrough infections.

More studies are necessary to confirm this.

“We are still uncertain whether people with post-COVID-19 conditions are more susceptible to breakthrough infections compared to those without those conditions,” Hsu said. “We are still learning more about the risks, management, and treatment of post-COVID-19 conditions and hope to learn more in subsequent studies.”

According to the Centers for Disease Control and Prevention’s COVID Data Tracker, fully vaccinated individuals who got their booster or additional dose are significantly less likely to get hospitalized for COVID-19 than unvaccinated people.

It’s important for immunocompromised individuals to get their recommended additional dose, and everyone who is fully vaccinated is encouraged to get their booster shot.

“[The study] should also serve as a reminder of the seriousness of this disease and the importance of staying up to date on COVID-19 vaccinations to reduce one’s risk of infection with COVID-19 and its potential complications,” Hsu said.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.