2-Year Wuhan Follow-Up Offers New Insights into Long Covid

Over half of individuals hospitalized with Covid-19 at a single center in Wuhan, Cina continued to have symptoms related to the disease 2 years after hospital discharge, according to findings from the longest longitudinal follow-up study of long Covid reported to date.

The study included patients treated for Covid-19 and later discharged from a single hospital, Jin Yin-tan Hospital in Wuhan, China, between early January and late May 2020.

While the vast majority of patients reported improvements in both physical and mental health symptoms over the 2-years of follow-up, 55% reported at least one symptom believed to be related to their illness at 2-year follow-up, compared to 68% at 6-month follow-up. Fatigue and sleep difficulties were among the most commonly reported long-Covid symptoms, along with increased difficulty exercising.

The study findings, published in the journal Lancet Respiratory Medicine, highlight the "urgent need to explore the, MD, pathogenesis of long Covid and develop effective interventions to reduce the risk of long Covid," wrote researcher Bin Cao of the China-Japan Friendship Hospital at Capital Medical University in Beijing, China, and colleagues.

"Our findings indicate that for a certain proportion of hospitalized Covid-19 survivors, while they may have cleared the initial infection, more than two years is needed to recover fully from Covid-19," Cao noted in a press statement. "Ongoing follow-up of Covid-19 survivors, particularly those with symptoms of long Covid, is essential to understanding the longer course of the illness, as is further exploration of the benefits of rehabilitation programs for recovery."

While several previously published studies examined long Covid symptoms up to a year after initial infection with SARS-CoV-2, the study by Cao and colleagues is the first to report outcomes among patients hospitalized with the disease two years earlier. Their ambidirectional, longitudinal study included some of the first patients hospitalized with Covid-19.

Of the 2,469 Covid-19 patients treated at Jin Yin-tan Hospital in Wuhan who were discharged between Jan. 7 and May 29, 2020, 1,192 completed follow-up assessments at three health visits 6 months, 12 months, and 24 months after discharge, Cao and colleagues explained. These patients, which included a subset receiving pulmonary function testing and chest imaging at each follow-up visit, were included in the analysis.

Median patient age at hospital discharge was 57 years (range 48 to 65 years) and 54% were male. The median follow-up time after symptom onset was 185 days for the 6-month visit, 349 days for the visit at 12 months, and 685 days for the visit at 2 years.

Age-, sex- and comorbidity-matched subjects without a history of Covid-19 infection served as controls in the study.

Among the main study findings:

• 68% of patients included in the analysis reported at least one sequelae symptom at 6-month follow-up, compared to 55% at 2 years.
• 14% of Covid-19 survivors reported shortness of breath (measured by an mMRC dyspnea score of at least 1) at 2 years, compared to 26% with shortness of breath at 6 months (P<0.0001).
• Patients saw improvements in health-related quality-of-life in most domains, "especially in terms of anxiety or depression: the proportion of individuals with symptoms of anxiety or depression decreased from 256 (23%) of 1,105 at 6 months to 143 (12%) of 1,191 at 2 years (P<0.0001)."
• At the 2-year follow-up, 31% of those hospitalized with Covid reported fatigue or muscle weakness, and the same percentage reported having sleep issues, compared to 5% and 14%, respectively, of controls who had not had Covid-19.
• Covid patients were also roughly twice as likely to report pain or discomfort (23% versus 5% of controls) and anxiety and depression (12% versus 5%).
• The proportion of survivors with a 6-minute walk distance (6MWD) test less than the lower limit of the normal range "declined continuously in Covid-19 survivors overall and in the three subgroups of varying initial disease severity."

A total of 438 (89%) of 494 Covid-19 survivors included in the follow-up study were back at their original job at 2 years post-discharge.

A study limitation cited by the researchers was the lack of a control group of people hospitalized for respiratory illness unrelated to Covid-19. "Without a control group of hospitalized survivors of respiratory infection other than Covid-19, it is hard to establish whether the observed abnormalities are specific to Covid-19," they pointed out.

The study authors concluded that while the cohort, as a whole, showed continued recovery over the follow-up period, regardless of initial disease severity, "a fairly high burden of symptoms was still seen at 2 years. The Covid-19 survivors had not returned to the same health status as the general population 2 years after acute infection, so ongoing follow-up is needed to characterize the protracted natural history of long Covid; we plan to conduct yearly follow-ups in this cohort."

The study authors had no relevant relationships to disclose.

Huang L, et al "Health outcomes in people 2 years after surviving hospitalization with Covid-19: a longitudinal cohort study" Lancet Respir Med 2022; DOI: 10.1016/S2213-2600(22)00126-6.