Symptom based and transmission-prevention based testing in long-term care facilities: Symptomatology, clinical course and mortality for residents with COVID-19 (preprint)

Objectives: Initially, for preventing COVID-19 transmission in long-term care facilities (LTCF) primarily rely on presence of core symptoms (fever, cough, dyspnea), but LTCF residents may also show an atypical course of a SARS-CoV-2 infection. We described the clinical presentation and course of COVID-19 in LTCF residents who were tested either because of presence of core symptoms (S-based) or because of transmission prevention (TP-based) Design: Retrospective cohort study. Setting and participants: Amsta (Amsterdam, The Netherlands), is a 1185-bed LTCF. All LTCF residents who underwent SARS-CoV-2 RT-PCR testing between March 16, 2020 and May 31, 2020 were included (n = 380). Measures: Clinical symptoms, temperature and oxygen saturation were extracted from medical records, 7 days before testing up to 14 days after testing. Results: SARS-CoV-2 was confirmed in 81 (21%) residents. Of these 81, 36 (44%) residents were tested S-based and 45 (56%) residents were tested TP-based. Yet, CT-values did not differ between the groups. In the 7 days prior to the test the most common symptoms in both groups were: falling (32%), somnolence (25%) and fatigue (21%). Two days before the test, we observed a stronger decrease in oxygen saturation and an increase in temperature for the S-based group compared to the T-based group that remained up to 10 days after testing. Residents with in the S-based group were 2.5 times more likely to decease within 30 days than residents in the TP-based group (HR, 2.56; 95% 1.3 to 5.2). Even though, 73% of the T-based group did eventually developed core symptoms. Conclusion and implications: Many LTCF residents with a positive PCR did not have core symptoms when tested but had other signs/symptoms in the week before the positive test. Testing policies should therefore be adjusted to prevent transmission. Daily measures of temperature and oxygen saturation can contribute to earlier detection.

Clinical Suspicion of COVID-19 in Nursing Home residents: symptoms and mortality risk factors (preprint)

Objectives To describe symptomatology, mortality and risk factors for mortality in a large group of Dutch nursing home (NH) residents with clinically-suspected COVID-19 who were tested with a Reverse Transcription Polymerase Chain Reaction (RT-PCR) test. Design Prospective cohort study. Setting and participants Residents of Dutch NHs with clinically-suspected COVID-19 and who received RT-PCR test. Methods We collected data of NH residents with clinically-suspected COVID-19, via electronic health records between March 18th and May 13th, 2020. Registration was performed on diagnostic status (confirmed (COVID-19+)/ruled out (COVID-19-)) and symptomatology (typical and atypical symptoms). Information on mortality and risk factors for mortality were extracted from usual care data. Results In our sample of residents with clinically-suspected COVID-19 (N=4007), COVID-19 was confirmed in 1538 residents (38%). Although, symptomatology overlapped between residents with COVID-19+ and COVID-19-, those with COVID-19+ were three times more likely to die within 30 days (hazard ratio (HR), 3.1; 95% CI, 2.7 to 3.6). Within this group, mortality was higher for men than for women (HR, 1.8; 95%, 1.5-2.2) and we observed a higher mortality for residents with dementia, reduced kidney function, and Parkinson's Disease, even when corrected for age, gender, and comorbidities. Conclusions and implications About 40% of the residents with clinically-suspected COVID-19 actually had COVID-19, based on the RT-PCR test. Despite an overlap in symptomatology, mortality rate was three times higher for residents with COVID-19+. This emphasizes the importance of using low-threshold testing in NH residents which is an essential prerequisite to using limited personal protective equipment and isolation measures efficiently.