Three-quarters of patients previously hospitalized with COVID-19 continued to report at least one symptom six months later, Chinese researchers found.
Fatigue or muscle weakness were by far the most common symptoms (63%), followed by sleep difficulties (26%), and 23% of patients said they had anxiety or depression, reported Bin Cao, MD, of China-Japan Friendship Hospital in Beijing, and colleagues, writing in The Lancet.
“Our analysis indicates that most patients continue to live with at least some of the effects of the virus after leaving the hospital, and highlights a need for post-discharge care, particularly for those who experience severe infections,” Cao said in a statement. “Our work also underscores the importance of conducting longer follow-up studies in larger populations in order to understand the full spectrum of effects that COVID-19 can have on people.”
It’s the largest cohort with the longest follow-up so far for adult patients hospitalized with COVID-19, as researchers around the world examine the so-called “long COVID” phenomenon. Other recent studies focused on long-term neurologic symptoms in patients in Italy, as well as abnormalities in the lungs in British patients.
Cao and colleagues also noted, “no studies have yet reported the extrapulmonary organ manifestations that could persist after damage in acute stage or are new onset after discharge.”
They examined data from 1,733 patients discharged from one Wuhan hospital from Jan. 7 to May 29 and followed from June 16 to Sept. 3. They were given physical examinations, interviewed about their quality of life, did a 6-minute walking test and had blood drawn. Some patients also underwent pulmonary function tests and high-resolution chest CTs.
Patients’ mean age was 57, and 52% were men. Median follow-up after symptom onset was 186 days. Almost 30% of patients had hypertension, 12% had diabetes, and 7% had cardiovascular disease. Almost 70% of patients required oxygen during their hospital stay and 4% were admitted to an ICU. Median hospital stay was 14 days.
Researchers used a seven-stage severity scale ranging from no hospital admission to hospitalization requiring intubation or extracorporeal membrane oxygenation.
A little under 30% of the most severe patients (stages 5-6 on the scale) had median 6-minute walk distance less than the lower limit of normal range at follow-up.
Among 349 participants who completed the lung function test, 56% of the most severely ill patients had lung diffusion impairment. The authors also noted more severely ill patients had increased risk of fatigue or muscle weakness and anxiety or depression.
Moreover, 13% of patients with normal kidney function presented with decreased estimated globular filtration rate (eGFR) at follow-up, among 822 with available eGFR data.
But an accompanying editorial by Giuseppe Remuzzi, MD, of Istituto di Ricerche Farmacologiche Mario Negri in Bergamo, Italy, and colleagues cautioned on these findings, noting GFR-estimating equations “do not enable a sound assessment of renal function, which can be overestimated or underestimated compared with measured GFR.”
On the other hand, they noted that deep vein thrombosis was not diagnosed in any patients at follow-up, calling this an “encouraging finding,” given how many patients develop the condition while hospitalized.
The editorialists pointed out that only 4% of the cohort were admitted to an ICU, allowing no meaningful conclusions about the most severely ill patients.
Other limitations noted by Bao and colleagues include that baseline pulmonary function and 6-min walk distance were unavailable, and new symptoms following COVID-19 were not stratified to determine if they were persistent or worsened following recovery or occurred post-discharge. As well, milder cases were not included in the study.
Remuzzi and colleagues echoed the authors’ calls for longer follow-up in larger populations.
“These studies will improve our understanding of the natural history of COVID-19 sequelae and the factors or mediators involved, and enable us to assess the efficacy of therapeutic interventions to mitigate the long-term consequences of COVID-19 on multiple organs and tissues,” Remuzzi and colleagues wrote.
This work was supported by the National Natural Science Foundation of China; Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences; the National Key Research and Development Program of China; and Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis, Peking Union Medical College Foundation (the China Evergrande Group, Jack Ma Foundation, Sino Biopharmaceutical, Ping An Insurance [Group], and New Sunshine Charity Foundation).
Huang and colleagues disclosed no conflicts of interest.
Remuzzi disclosed support from Alexion Pharmaceuticals Inc, Janssen Pharmaceutical, Akebia Therapeutics, Alnylam, Boehringer Ingelheim, Inception Sciences Canada, Omeros, and Catalyst Biosciences.
Other co-authors disclosed no conflicts of interest.