Post-covid-19 condition affects 20-30% of unvaccinated individuals three to six months after SARS-CoV-2 infection.12345678910111213 To adequately inform patients, healthcare providers, and policy makers, not only is determining prevalence important but also its natural course over time.14 As evidence on the substantial public health burden of post-covid-19 condition accumulates, clinical trials are necessary to establish interventions that accelerate recovery or provide relief for associated symptoms. A solid understanding of trajectories and relevant outcome measures of post-covid-19 condition is required to effectively design and adequately interpret such trials.
Several studies assessed long term outcomes related to post-covid-19 condition and found that 22-75% of individuals had symptoms for more than a year after infection.31516171819202122232425 Most of these studies included specific populations, such as patients in hospital, focused on a specific dimension of post-covid-19 condition, did not have a prospective follow-up, or suffered from relevant attrition rates. Thus, these studies might not reflect the variability of symptoms and recovery over time, and their generalisability across the severity spectrum of acute covid-19 might be limited. Additionally, most studies assessing post-covid-19 condition did not have a comparator group, and their findings were often questioned because many reported symptoms were non-specific and common in the general population without an infection. Limited knowledge and no consensus on core outcomes regarding post-covid-19 condition has led to the use of various outcome measures across observational studies affecting their comparability.26 These issues also impair the interpretation of trials of interventions targeting post-covid-19 condition and their translation into healthcare policy and clinical practice.
Intro:
Post-covid-19 condition affects 20-30% of unvaccinated individuals three to six months after SARS-CoV-2 infection.12345678910111213 To adequately inform patients, healthcare providers, and policy makers, not only is determining prevalence important but also its natural course over time.14 As evidence on the substantial public health burden of post-covid-19 condition accumulates, clinical trials are necessary to establish interventions that accelerate recovery or provide relief for associated symptoms. A solid understanding of trajectories and relevant outcome measures of post-covid-19 condition is required to effectively design and adequately interpret such trials.
Several studies assessed long term outcomes related to post-covid-19 condition and found that 22-75% of individuals had symptoms for more than a year after infection.31516171819202122232425 Most of these studies included specific populations, such as patients in hospital, focused on a specific dimension of post-covid-19 condition, did not have a prospective follow-up, or suffered from relevant attrition rates. Thus, these studies might not reflect the variability of symptoms and recovery over time, and their generalisability across the severity spectrum of acute covid-19 might be limited. Additionally, most studies assessing post-covid-19 condition did not have a comparator group, and their findings were often questioned because many reported symptoms were non-specific and common in the general population without an infection. Limited knowledge and no consensus on core outcomes regarding post-covid-19 condition has led to the use of various outcome measures across observational studies affecting their comparability.26 These issues also impair the interpretation of trials of interventions targeting post-covid-19 condition and their translation into healthcare policy and clinical practice.