Post-acute symptoms, new onset diagnoses and health problems 6 to 12 months after SARS-CoV-2 infection: a nationwide questionnaire study in the adult Danish population

Abstract

Background. A considerable number of individuals infected with SARS-CoV-2 continue to experience symptoms after the acute phase. More information on duration and prevalence of these symptoms in non-hospitalized populations is needed. Methods. We conducted a nationwide cross-sectional study including 152 880 individuals aged 15-years or older, consisting of RT-PCR confirmed SARS-CoV-2 cases between September 2020-April 2021 (N=61 002) and a corresponding test-negative control group (N=91 878). Data were collected 6, 9 or 12 months after the test using web-based questionnaires. The questionnaire covered acute and post-acute symptoms, selected diagnoses, sick leave and general health, together with demographics and life style at baseline. Risk differences (RDs) between test-positives and -negatives were reported, adjusted for age, sex, single comorbidities, Charlson comorbidity score, obesity and healthcare-occupation. Findings. Six to twelve months after the test date, the risks of 18 out of 21 physical symptoms were elevated among test-positives and one third (29.6%) of the test-positives experienced at least one physical post-acute symptom. The largest risk differences were observed for dysosmia (RD = 10.92%, 95%CI 10.68-11.21%), dysgeusia (RD=8.68%, 95%CI 8.43-8.93%), fatigue/exhaustion (RD=8.43%, 95%CI 8.14-8.74%), dyspnea (RD=4.87%, 95%CI 4.65-5.09%) and reduced strength in arms/legs (RD=4.68%, 95%CI 4.45-4.89%). More than half (53.1%) of test-positives reported at least one of the following conditions: concentration difficulties (RD=28.34%, 95%CI 27.34-28.78%), memory issues (RD=27.25%, 95%CI 26.80-27.71%), sleep problems (RD=17.27%, 95%CI 16.81-17.73%), mental (RD=32.58%, 95%CI 32.11-33.09%) or physical exhaustion (RD=40.45%, 95%CI 33.99-40.97%), compared to 11.5% of test-negatives. New diagnoses of anxiety (RD=1.15%, 95%CI 0.95-1.34%) or depression (RD=1.00%, 95%CI 0.81-1.19%) were also more common among test-positives. Interpretation. At the population-level, where the majority of test-positives (96.0%) were not hospitalized during acute infection, a considerable proportion experience post-acute symptoms and sequelae 6-12 months after infection. Funding. None

Long-term symptoms after SARS-CoV-2 infection in a cohort of hospital employees: duration and predictive factors

“…Just recently, a nationwide cross-sectional study in the Danish population with over 60.000 SARS-CoV-2 positive persons and a SARS-CoV-2 negative control group revealed significant risk differences for anosmia, fatigue/exhaustion, dyspnea and reduced strengths in legs/arms. 6 Our data, which do not include control groups, are consistent with the findings of the Danish questionnaire study.…”

“…These symptoms may nevertheless be essential to understand the burden of post-COVID conditions. 6 In comparison to the work of Augustin et al with a prevalence of 35% for six months lasting symptoms, 7 in our cohort the prevalence of long-lasting symptoms after three months was at 47% of hospital employees, hence, being comparable. Augustin et al defined the occurrence of at least one long lasting symptom out of four (anosmia, ageusia, fatigue, shortness of breath) as post-COVID syndrome.…”

“…The Danish cross-sectional study by Vedel Sørensen et al as well as the findings of Roessler et al confirmed our data. 6,17 Roessler et al conducted a matched cohort study based on routine health insurance data of more than 45 percent of the German population with a COVID-19 cohort including nearly 160.000 individuals. 17 As an additional limitation of our study, it must be mentioned that we only asked about subjectively perceived symptoms that were not necessarily confirmed by a physician.…”

“…1,2 In contrast to more frequently studied long-lasting symptoms after severe COVID-19 courses, [3][4][5] we were surprised by the amount of symptoms that also occurred after mild courses not requiring hospitalization. Since the vast majority of people infected with SARS-CoV-2 do not need to be hospitalized, 6,7 it is of great importance to also consider mild COVID-19 cases with regard to long-lasting COVID-19 symptoms.…”

Post-acute health care burden after SARS-CoV-2 infection: A retrospective cohort study of long COVID among 530,892 adults

“…Previous work indicates that 10-40% of individuals report symptoms months after acute COVID-19, including those who were not hospitalized initially, although these estimates vary by population and definitions of cases and outcomes. 46,47 A subset of PCR test-positive individuals in Denmark who were contacted found that 53% reported symptoms 6-12 months after infection, 48 and 5% of respondents in a study conducted in South Korea reported they were receiving treatment for symptoms a median of 454 days after their COVID-19 diagnosis. 49 Several large studies conducted in the United States Veterans Health Administration health care system, ~90% of whom were men and more than 70% were White, found increased outpatient clinic visits after hospitalization for COVID-19 or a positive SARS-CoV-2 PCR test, as well as increased risk of myocardial infarction and stroke in the months after infection; these findings may not be generalizable to other populations.…”