Although nonhospitalized COVID-19 patients are at low risk for delayed complications, they visit their general practitioner or clinic more often than their uninfected peers in the 6 months after testing positive, finds a population-based study published yesterday in The Lancet Infectious Diseases.
The study, led by researchers from the University of Southern Denmark, involved comparing 8,983 living, nonhospitalized COVID-19 patients with 80,894 Danish residents who tested negative for the virus from Feb 27 to May 31, 2020. Both groups were followed for 2 weeks to 6 months after testing.
Both groups were at similar risk for being diagnosed as having a new health condition at a hospital (risk difference [RD], 26.3% vs 28.8%), but COVID-19 patients were more likely to be diagnosed as having breathing problems (RD, 1.2% vs 0.7%; adjusted RR [aRR], 2.00) or venous thromboembolism (blood clots in the veins) (RD, 0.2% vs 0.1%; aRR, 1.77).
The risk of death or serious coronavirus complications previously identified in hospitalized coronavirus patients, such as stroke, encephalitis, psychosis, and diagnoses related to multisystem inflammatory syndrome in children, were not increased among nonhospitalized COVID-19 patients.
Thirty-one percent of COVID-19 patients started new medications during follow-up, including bronchodilators (score-weighted RD, 1.8% vs 1.5%; aRR, 1.23) and triptans to alleviate migraines (RD, 0.4% vs. 0.3%; aRR, 1.55).
Compared with the coronavirus-negative group, COVID-19 patients visited their general practitioners 1.2 times more often and clinics 1.1 times more often. But both groups were equally likely to visit the emergency department or be admitted to the hospital. Median age was 43 years, and 63.5% were female.
Findings may be underestimate
In a Lancet news release, senior study author Anton Pottegard, DMSc, PhD, of the University of Southern Denmark, said that most research has focused on hospitalized COVID-19 patients, but most coronavirus patients aren't hospitalized.
"Our research provided evidence for some long-term effects that did not require hospitalisation or the use of new medicines, which we found reflected in higher use of primary health-care services after infection," Pottegard said. "This highlights the need to ensure clinicians have the resources and support to manage any potential long-term conditions."
Coauthor Stine Hasling Mogensen, PhD, of the Danish Medicines Agency, said that the study likely missed symptoms not likely to require hospital care, such as fatigue or mild breathing problems. "Previous research has found a high level of these symptoms reported by patients, so the differences between patient reports and healthcare encounters could be important to investigate in regards to potential unmet healthcare needs and the need for new medications for treatment," she said.
The researchers called for large population-based studies of self-reported symptoms and medical visits to investigate the duration and breadth of persistent symptoms after recovery from COVID-19.
Patients with preexisting risk factors
In a commentary in the same journal, Lixue Huang, MD, of Capital Medical University, and Bin Cao, MD, of China-Japan Friendship Hospital, both in Beijing, said that the findings should prompt clinicians to pay particular attention to COVID-19 patients who already had risk factors for breathing problems, such as chronic lung disease, heart failure, and pulmonary hypertension.
"Monitoring respiratory rate and oxygen saturation at home were simple and practical ways for these patients to assess their respiratory function and health status," they said.
Likewise, healthcare providers should closely monitor COVID-19 patients at risk for venous thromboembolism, such as older patients and those with elevated levels of D-dimer (indicating blood clots) and underlying diseases such as cancer and immobility, they added.
"Considering the possibility of an underestimate, the short follow-up time, and the huge numbers of SARS-CoV-2 infections worldwide, venous thromboembolism could be a potential concern," Huang and Cao wrote. "In the future, follow-up clinics are needed to establish longer-term outcomes in this population and explore strategies to prevent and mitigate sequelae of COVID-19."