A Risk Score Proposal for Covid-19 in Nursing Homes
Ambra Raimondi MD, Gianluigi Poma MD, Domenico Zanaboni MD, Carolina Dellafiore MD, Elisabetta Above MD, Andrea Agostinelli MD, Catherine Klersy MD, Virginia Valeria Ferretti PhD, Anna Maria Grugnetti PhD, Andrea Falconeri MD, Vittoria Infantino MD, Lorena Sega MD, Valeria Meroni PhD, Antonio Piralla PhD, Fausto Baldanti MD and Carlo Filice MD
Background/Objectives: During the SARS-CoV-2 pandemic currently ongoing worldwide, several challenges were encountered in managing patients in out-of-hospital residences. The aim of this study is to establish a risk score indicating the probability of SARS-CoV-2 infection and estimate the seroprevalence in nursing homes.
Design: This is a retrospective cross-sectional observational study.
Participants and Setting: 231 patients (median age 86 years, min 53 max 100 years) were enrolled from three nursing homes of Pavia and its surroundings.
Measurements: Medical history, clinical and instrumental data were correlated to the results of nasopharyngeal swab and serology.
Results: Patients with positive nasopharyngeal swab and/or serology were 170 (74%, 95%CI: 67%-79%) and seroprevalence was 64%. Variables associated with COVID-19 infection used to build the clinical score were: anosmia and ageusia, pulse oximetry <90%, conjunctivitis, rhinorrhea, myalgia. The probability of COVID-19 positivity increased linearly over the clinical score values (score 0: 55%; score 1: 83%: score 2+: 95%). By adding lung ultrasound to the score, a Clinical & LUS Risk Score was created, which allowed further stratification. The area under the ROC Curve for the two models was 0∙73 and 0∙77, respectively. Of note, fever, one of the pivotal signs in COVID-19 patients, was not a common manifestation among nursing home residents with SARS-CoV-2 infection, therefore it was not included in the scores.
Conclusions: Given the high SARS-CoV-2 seroprevalence in nursing homes, the Clinical San Matteo Risk Score, implemented by lung ultrasound when available, can help for an early identification, isolation and treatment of possible positive cases.