Clinical validation of SARC-F by proxy as a practical tool to evaluate sarcopenia in dependent older adults.

INTRODUCTION: Sarcopenia is a prevalent disorder in older adults with significant adverse outcomes and regular screening is recommended for those at risk. The SARC-F questionnaire is the most commonly recommended screening tool for sarcopenia. However, as a self-reported tool, it cannot be applied to dependent individuals with communication problems. We hypothesized that implementation of the proxy-reported SARC-F (SARC-F by proxy) would be non-inferior in screening sarcopenia when compared with the standard SARC-F. Thus, we aimed to investigate the clinical validity of the SARC-F by proxy in identifying sarcopenia in older adults and to compare its performance with the standard SARC-F. Additionally, we aimed to determine the ideal cut-off of SARC-F by proxy in screening sarcopenia. MATERIALS AND METHODS: This is a validation study including older adults aged ≥60 years without communication problems and their close proxies. The participants were recruited from a geriatric outpatient clinic of a tertiary health center and a nursing home. Standard SARC-F was transformed to SARC-F by proxy and administered to the proxies of older adults, and standard SARC-F was administered to the patients simultaneously in different rooms. We defined sarcopenia as probable and confirmed by the EWGSOP2 consensus report. We performed receiver operating characteristics (ROC) and sensitivity/specificity analyses of SARC-F by proxy for diagnosing sarcopenia and compared its performance with standard SARC-F by the DeLong test. RESULTS: We included 172 older adults (median age: 72; 44.8% female) and 107 proxies in close contact (median age: 55, 63.2% female). The prevalence of probable and confirmed sarcopenia was 18.9% and 12.9%, respectively. For both definitions, area under the curve (AUC) values of SARC-F by proxy and standard SARC-F were moderate and similar [probable sarcopenia: 0.619 and 0.624 (p = 0.9); confirmed sarcopenia 0.613 and 0.645 (p = 0.7), respectively]. The best balance between sensitivity and specificity was achieved with a SARC-F by proxy score of ≥2 for both sarcopenia definitions (sensitivity levels were 74.7% and 77.8%, and specificity levels were 50.0% and 49.6%, for probable and confirmed sarcopenia, respectively). DISCUSSION: SARC-F by proxy showed a similar, non-inferior performance compared to the standard SARC-F in the evaluation of sarcopenia. Our results suggest that it can be used instead of standard SARC-F to screen sarcopenia in older patients with communication problems. Further validation studies in different populations are warranted to support our findings.

Evaluation of the Diagnostic Performance of a SARS-CoV-2 and Influenza A/B Combo Rapid Antigen Test in Respiratory Samples.

This study aimed to evaluate the performance characteristics of a rapid antigen test developed to detect SARS-CoV-2 (COVID-19), influenza A virus (IAV), and influenza B virus (IBV) (flu) compared with those of the real-time reverse transcription-polymerase chain reaction (rRT-PCR) method. One hundred SARS-CoV-2, one hundred IAV, and twenty-four IBV patients whose diagnoses were confirmed by clinical and laboratory methods were included in the patient group. Seventy-six patients, who were negative for all respiratory tract viruses, were included as the control group. The Panbio™ COVID-19/Flu A&B Rapid Panel test kit was used in the assays. The sensitivity values of the kit were 97.5%, 97.9%, and 33.33% for SARS-CoV-2, IAV, and IBV, respectively, in samples with a viral load below 20 Ct values. The sensitivity values of the kit were 16.7%, 36.5%, and 11.11% for SARS-CoV-2, IAV, and IBV, respectively, in samples with a viral load above 20 Ct. The kit's specificity was 100%. In conclusion, this kit demonstrated high sensitivity to SARS-CoV-2 and IAV for viral loads below 20 Ct values, but the sensitivity values were not compatible with PCR positivity for lower viral loads over 20 Ct values. Rapid antigen tests may be preferred as a routine screening tool in communal environments, especially in symptomatic individuals, when diagnosing SARS-CoV-2, IAV, and IBV with high caution.

[Evaluation of the Diagnostic Performance of SARS-CoV-2 Rapid Antigen Tests in COVID-19 Patients]. / SARS-CoV-2 Hizli Antijen Testlerinin COVID-19 Hastalarindaki Tanisal Performanslarinin Degerlendirilmesi.

The gold standard in the definitive diagnosis of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is nucleic acid amplification tests (NAAT) due to their high sensitivity and specificity in detecting viral ribonucleic acid. However, while leaving two years behind in the pandemic, resources have come to the point of exhaustion in terms of both the economy and the manpower working in the field of health services. Therefore, the need for rapid, simple and accurate tests to diagnose SARS-CoV-2 infection continues. In this study, it was aimed to compare the performance characteristics of SARS-CoV-2 rapid antigen tests (RAgT) in the diagnosis of coronavirus disease 2019 (COVID-19) cases with the real-time reverse transcription-polymerase chain reaction (rRT-PCR) method. In Istanbul University-Cerrahpasa Faculty of Medicine COVID-19 Molecular Diagnosis Laboratory, SARS-CoV-2 RNA positive respiratory tract samples with viral loads of <25 Ct (cycle of treshold), 25-29 Ct, 30-35 Ct and 35