Clinical Suspicion of COVID-19 in Nursing Home Residents: Symptoms and Mortality Risk Factors

Abstract

Objectives: To describe the 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 18 and May 13, 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 3 times more likely to die within 30 days [hazard ratio (HR), 3.1, 95% confidence interval (CI) 2.7-3.6]. Within this group, mortality was higher for men than for women (HR 1.8, 95% CI 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 3 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.

Keywords: Long-term care facility; SARS-CoV-2; cohort; survival analyses.

Fig. 1

Kaplan-Meier estimates of survival: (A) NH residents with confirmed and ruled out COVID-19. The blue line indicates the 30-day survival probability of NH residents in whom COVID-19 was ruled out; the red line indicates the 30-day survival probability of NH residents with confirmed COVID-19. The triangles indicate censored data points. (B) Men and women with confirmed COVID-19. The dashed line indicates the 30-day survival probability of women with confirmed COVID-19; the solid line indicates the 30-day survival probability of men with confirmed COVID-19. The triangles indicate censored data points.

Supplementary Figure 1

Flow chart.