Amid the coronavirus disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), efforts to study the long-term effects of the illness have focused largely on hospitalized patients who experienced severe illness.
A majority of patients experience only mild symptoms or are asymptomatic. However, it is still unclear if these patients can still suffer lasting effects of the infection.
In a new study published in The Lancet, a team of researchers examined prescription drug and healthcare use after SARS-CoV-2 infection in those who did not require hospital admission.
The researchers at the University of Southern Denmark aimed to determine the effects of mild SARS-CoV-2 infection in patients after recovering from the illness. The team has found that the risk of delayed acute complications after mild COVID-19 not requiring hospitalization is low. However, many of these individuals tend to have persistent symptoms, prompting increased doctor visits in the six months following infection.
COVID-19 long-haulers
As the pandemic has evolved, many cases of post-viral complications have emerged. COVID-19 long-haulers have exhibited a range of persistent symptoms long after viral clearance. Some of these symptoms include cough, fatigue, body pains, shortness of breath, insomnia, headache, and brain fog.
Most of the patients who experience persistent symptoms were those who were admitted to the hospital due to moderate and severe COVID-19. Some of these delayed complications include encephalitis, pulmonary fibrosis, thromboembolic events, and psychiatric illness.
However, there is limited evidence about complications among those who were not admitted to the hospital.
Increased doctor visits
The team conducted a population-based cohort study using the Danish prescription, patient, and health insurance registries. Overall, the team determined 10,498 patients who tested positive for COVID-19 via the reverse transcription-polymerase chain reaction (RT-PCR) test in Denmark between February 27 and May 31, 2020. Of these, the team followed 8,983 non-hospitalized COVID-19 patients and 80,894 COVID-19 negative people during the period of two weeks to six months after their test.
The team aimed to find reports of delayed acute complications, chronic illness, hospital visits due to persistent symptoms, the use of prescription drugs. They compared the data between the two groups and evaluated the risk of starting new drugs and receiving a diagnosis of a new health condition.
Among the patients who had COVID-19, 31 percent had started new drug treatments during the follow-up period. The team also revealed that compared with those who had a negative PCR test for SARS-CoV-2, those who tested positive were at a heightened risk of starting new drugs to dilate the airways and treat migraines.
Further, those who tested positive were at an elevated risk of receiving hospital diagnoses of dyspnea or shortness of breath and venous thromboembolism compared with those who had a negative test.
COVID-19 patients had more doctor visits and outpatient hospital visits compared with SARS-CoV-2-negative individuals.
Overall, the absolute risk of delayed acute complications, new onset of chronic disease, and hospital visits for persistent symptoms two weeks to six months after SARS-CoV-2 infection that does not require hospital admission were low.
However, among those with no or mild symptoms, there was still an increased risk of receiving hospital diagnosis of dyspnea, developing venous thromboembolism, starting bronchodilator therapy, and initiating triptans compared with those who tested negative for the infection.
SARS-CoV-2 positive patients visited their doctors more after the primary infection than those who tested negative. This means that those who recovered from mild COVID-19 may still experience persistent symptoms.
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