The Lancet Respiratory Medicine: A research follow up study on covid19
October 5, 2022

The Lancet Respiratory Medicine: Two years after infection, half of the people hospitalised with COVID-19 have at least one symptom, a follow-up study suggests

  • A study of 1,192 participants hospitalised with COVID-19 in Wuhan, China, between January 7th and May 29th, 2020, followed up at six months, 12 months, and two years after discharge.
  • Physical and mental health improved over time regardless of initial disease severity, with 55% reporting at least one symptom caused by the initial COVID-19 infection at two years compared to 68% at six months.
  • In general, patients who recovered from COVID-19 tend to be in poorer health two years after the initial infection compared to the general population, indicating some patients need more time to recover fully.
  • Around half of the study, participants had symptoms of long COVID – such as fatigue and sleep difficulties – at two years and experienced poorer quality of life and ability to exercise more mental health issues, and increased use of health-care services compared to those without symptoms of long COVID. 

Two years after infection with COVID-19, half of the patients admitted to the hospital still have at least one symptom, according to the most comprehensive follow-up study published in The Lancet Respiratory Medicine. The study followed 1,192 participants in China infected with SARS-CoV-2 during the first phase of the pandemic in 2020.

While physical and mental health generally improved over time, the analysis suggests that COVID-19 patients still have poorer health and quality of life than the general population. This is especially the case for participants with long COVID, who typically still have at least one symptom, including fatigue, shortness of breath, and sleep difficulties two years after initially falling ill.

The long-term health impacts of COVID-19 have remained largely unknown, as the most comprehensive follow-up studies to date have spanned around one year. The lack of pre-COVID-19 health status baselines and comparisons with the general population in most studies has made it difficult to determine how good patients with COVID-19 have recovered.

Lead author Professor Bin Cao of the China-Japan Friendship Hospital, China, says: “Our findings indicate that for a certain proportion of hospitalised COVID-19 survivors, while they may have cleared the initial infection, more than two years is needed to recover fully from COVID-19. Ongoing follow-up of COVID-19 survivors, particularly those with symptoms of long COVID, is essential to understand the longer course of the illness and further explore the benefits of rehabilitation programmes for recovery. There is a clear need to provide continued support to a significant proportion of people who’ve had COVID-19 and understand how vaccines, emerging treatments, and variants affect long-term health outcomes.”

The new study’s authors sought to analyse the long-term health outcomes of hospitalised COVID-19 survivors and the specific health impacts of long COVID. They evaluated the health of 1,192 participants with acute COVID-19 treated at Jin Yin-tan Hospital in Wuhan, China, between January 7th and May 29th, 2020, at six months, 12 months, and two years.

Assessments involved a six-minute walking test, laboratory tests, and questionnaires on symptoms, mental health, health-related quality of life if they had returned to work and health-care use after discharge. The adverse effects of long COVID on quality of life, exercise capacity, mental health, and health-care service were determined by comparing participants with and without long COVID symptoms. Health outcomes at two years were determined using an age-, sex-, and comorbidities-matched control group of people in the general population with no history of COVID-19 infection.

The median age of participants at discharge was 57 years, and 54% (n=641) were men. Six months after initially falling ill, 68% (777/1,149) of participants reported at least one long COVID symptom. By two years after infection, symptoms had dropped to 55% (650/1,190). Fatigue or muscle weakness were the symptoms most often reported and fell from 52% (593/1,151) at six months to 30% (357/1,190) at two years. Regardless of their initial illness severity, 89% (438/494) of participants had returned to their original work after two years.

Two years after initially falling ill, patients with COVID-19 are generally in poorer health than the general population, with 31% (351/1,127) reporting fatigue or muscle weakness and 31% (354/1,127) reporting sleep difficulties. The proportion of non-COVID-19 participants reporting these symptoms was 5% (55/1,127) and 14% (153/1,127). COVID-19 patients were also more likely to report several other symptoms, including joint pain, palpitations, dizziness, and headaches. In quality of life questionnaires, COVID-19 patients also more often reported pain or discomfort (23% [254/1,127]) and anxiety or depression (12% [131/1,127]) than non-COVID-19 participants (5% [57/1,127] and 5% [61/1,127], respectively).

Around half of the study participants (650/1,190) had long COVID at two years and reported lower quality of life than those without long COVID. In mental health questionnaires, 35% (228/650) reported pain or discomfort, and 19% (123/650) reported anxiety or depression. The proportion of COVID-19 patients without long COVID saying these symptoms was 10% (55/540) and 4% (19/540) at two years. Long COVID participants also more often reported problems with their mobility (5% [33/650]) or activity levels (4% [24/540]) than those without long COVID (1% [8/540] and 2% [10/540], respectively).

Mental health assessments of long COVID participants found that 13% (83/650) displayed symptoms of anxiety and 11% (70/649) showed signs of depression, while for non-long COVID participants, the proportions were 3% (15/536) and 1% (5/540), respectively. Long COVID participants used healthcare services more often after being discharged, with 26% (169/648) reporting an outpatient clinic visit compared to 11% (57/538) of non-long COVID participants. At 17% (107/648), hospitalisation among long COVID participants was higher than the 10% (52/538) reported without long COVID.

The authors acknowledge limitations to their study. Without a control group of hospital survivors unrelated to COVID-19 infection, it is hard to determine whether observed abnormalities are specific to COVID-19. While the moderate response rate may introduce selection bias, most baseline characteristics were balanced between COVID-19 survivors included in the analysis and those who were not. The slightly increased proportion of participants included in the research who received oxygen suggests that those who did not participate in the study had fewer symptoms than those who did. This may result in an overestimate of the prevalence of long COVID symptoms. Being a single centre study from an early pandemic, the findings may not directly extend to the long-term health outcomes of patients infected with later variants. Like most COVID-19 follow-up studies, there is also the potential for information bias when analysing self-reported health outcomes. Some outcome measures, including work status and health-care use after discharge, were not recorded at all visits, meaning only partial analysis of long-term impacts.

Related Posts