Beyond Chronological Age: Frailty and Multimorbidity Predict In-Hospital Mortality in Patients With Coronavirus Disease 2019

Using Unsupervised Machine Learning to Identify Age- and Sex-Independent Severity Subgroups Among Patients with COVID-19: Observational Longitudinal Study

Background

Early detection and intervention are the key factors for improving outcomes in patients with COVID-19.

Objective

The objective of this observational longitudinal study was to identify nonoverlapping severity subgroups (ie, clusters) among patients with COVID-19, based exclusively on clinical data and standard laboratory tests obtained during patient assessment in the emergency department.

Methods

We applied unsupervised machine learning to a data set of 853 patients with COVID-19 from the HM group of hospitals (HM Hospitales) in Madrid, Spain. Age and sex were not considered while building the clusters, as these variables could introduce biases in machine learning algorithms and raise ethical implications or enable discrimination in triage protocols.

Results

From 850 clinical and laboratory variables, four tests—the serum levels of aspartate transaminase (AST), lactate dehydrogenase (LDH), C-reactive protein (CRP), and the number of neutrophils—were enough to segregate the entire patient pool into three separate clusters. Further, the percentage of monocytes and lymphocytes and the levels of alanine transaminase (ALT) distinguished cluster 3 patients from the other two clusters. The highest proportion of deceased patients; the highest levels of AST, ALT, LDH, and CRP; the highest number of neutrophils; and the lowest percentages of monocytes and lymphocytes characterized cluster 1. Cluster 2 included a lower proportion of deceased patients and intermediate levels of the previous laboratory tests. The lowest proportion of deceased patients; the lowest levels of AST, ALT, LDH, and CRP; the lowest number of neutrophils; and the highest percentages of monocytes and lymphocytes characterized cluster 3.

Conclusions

A few standard laboratory tests, deemed available in all emergency departments, have shown good discriminative power for the characterization of severity subgroups among patients with COVID-19.

Intrinsic Capacity Assessment by a Mobile Geriatric Team During the Covid-19 Pandemic

In the autumn of 2020, the second wave of the COVID-19 pandemic hit Europe. In this context, because of the insufficient number of beds in geriatric COVID units, non-geriatric wards were confronted with a significant number of admissions of geriatric patients. In this perspective article, we describe the role of a mobile geriatric team in the framework of the COVID-19 pandemic and specifically how it assisted other specialists in the management of hospitalized geriatric patients by implementing a new approach: the systematic assessment and optimization of Intrinsic Capacity functions. For each patient, assessed by this consultative team, an individualized care plan, including an anticipated end-of-life decision-making process, was established. Intensity of care was most often not stated by considering chronological age but rather the comorbidity burden, the frailty status, and the patient's wishes. Further studies are needed to determine if this mobile geriatric team approach was beneficial in terms of mortality, length of stay, or functional, psychological, and cognitive outcomes in COVID-19 geriatric patients.

Reliability, Validity, and Feasibility of the Frail-VIG Index

The study aimed to assess the reliability of the scores, evidence of validity, and feasibility of the Frail-VIG index. A validation study mixing hospitalized and community-dwelling older people was designed. Intraclass correlation coefficient (ICC) was used to assess the inter-rater agreement and the reliability. The construct validity of the Frail-VIG index with respect to the Frailty Phenotype (FP) was evaluated by calculating the area under the receiver operating characteristic curve (AUC-ROC). Convergent validity with the Clinical Frailty Scale (CFS) was assessed using Pearson's correlation coefficients. The feasibility was evaluated by calculating the average time required to administer the Frail-VIG index and the percentage of unanswered responses. A sample of 527 older people (mean age of 81.61, 56.2% female) was included. The inter-rater agreement and test-retest reliability were very strong: 0.941 (95% CI, 0.890 to 0.969) and 0.976 (95% CI, 0.958 to 0.986), respectively. Results indicated adequate convergent validity of the Frail-VIG index with respect to the FP, AUC-ROC 0.704 (95% CI, 0.622 to 0.786), and a moderate to strong positive correlation between the Frail-VIG index and CFS (r = 0.635, 95% CI, 0.54 to 0.71). The Frail-VIG index administration required an average of 5.01 min, with only 0.34% of unanswered responses. The Frail-VIG index is a reliable, feasible, and valid instrument to assess the degree of frailty in hospitalized and community-dwelling older people.

What is the relationship between validated frailty scores and mortality for adults with COVID-19 in acute hospital care? A systematic review

BACKGROUND AND AIM

The aim of this systematic review was to quantify the association between frailty and COVID-19 in relation to mortality in hospitalised patients.

METHODS

Medline, Embase, Web of Science and the grey literature were searched for papers from inception to 10 September 2020; the search was re-run in Medline up until the 9 December 2020. Screening, data extraction and quality grading were undertaken by two reviewers. Results were summarised using descriptive statistics, including a meta-analysis of overall mortality; the relationships between frailty and COVID-19 mortality were summarised narratively.

RESULTS

A total of 2,286 papers were screened resulting in 26 being included in the review. Most studies were from Europe, half from the UK, and one from Brazil; the median sample size was 242.5, median age 73.1 and 43.5% were female. In total, 22/26 used the Clinical Frailty Scale; reported mortality ranged from 14 to 65%. Most, but not all studies showed an association between increasing frailty and a greater risk of dying. Two studies indicated a sub-additive relationship between frailty, COVID-19 and death, and two studies showed no association.

CONCLUSIONS

Whilst the majority of studies have shown a positive association between COVID-19-related death and increasing frailty, some studies suggested a more nuanced understanding of frailty and outcomes in COVID-19 is needed. Clinicians should exert caution in placing too much emphasis on the influence of frailty alone when discussing likely prognosis in older people with COVID-19 illness.

Why data on frailty and SARS-CoV-2 infection are basic to progress

Several studies showed that frailty was a predictor of in-hospital death in older adults with COVID-19. The mechanisms through which frailty increases the severity of COVID-19 are several, including immunosenescense and dysregulated inflammation. Whether individuals affected by frailty exhibit a higher susceptibility to SARS-CoV-2 infection remains an open question. Here we report the case series of 40 older persons that in February 2020, before the first case of COVID-19 was detected in Italy, went together on a winter holiday. Back home, 7 of them developed influenza-like symptoms and one was hospitalized due to COVID-19 pneumonia. Between May and July, the seniors were offered the possibility to be tested for SARS-CoV-2 antibody positivity. Twenty-seven of them accepted: 13 had a positive serological test whereas no active infection was found. Comparing the characteristics of those who tested positive and the others, we found that the former group was frailer, exhibiting higher Clinical Frailty Scale scores.

COVID-19 mortality as a fingerprint of biological age

Corona virus disease 2019 (COVID-19) is a global emergency able to overwhelm the healthcare capacities worldwide and to affect the older generation especially. When addressing the pathophysiological mechanisms and clinical manifestations of COVID-19, it becomes evident that the disease targets pathways and domains affected by the main aging- and frailty-related pathophysiological changes. A closer analysis of the existing data supports a possible role of biological age rather than chronological age in the prognosis of COVID-19. There is a need for systematic, consequent action of identifying frail (not only older, not only multimorbid, not only symptomatic) persons at risk of poor outcomes.

Hypothetical COVID-19 protection mechanism: hints from centenarians

The risk of serious complications and the fatality rate due to COVID-19 pandemic have proven particularly higher in older persons, putting a further strain in healthcare system as we dramatically observed.

COVID-19 is not exclusively gerophile (géro “old” and philia “love”) as young people can be infected, even if older people experience more severe symptoms and mortality due to their greater frailty. Indeed, frailty could complicate the course of COVID-19, much more than the number of years lived. As demonstration, there are centenarians showing remarkable capacity to recover after coronavirus infection.

We hypothesize that centenarian’s portfolio could help in identifying protective biological mechanisms underlying the coronavirus infection.

The human leukocyte antigen (HLA) is one of the major genetic regions associated with human longevity, due to its central role in the development of adaptive immune response and modulation of the individual’s response to life threatening diseases. The HLA locus seems to be crucial in influencing susceptibility and severity of COVID-19.

In this hypothesis, we assume that the biological process in which HLA are involved may explain some aspects of coronavirus infection in centenarians, although we cannot rule out other biological mechanisms that these extraordinary persons are able to adopt to cope with the infection.

[COVID-19 in old age-The geriatric perspective]

Predominantly the older population is affected by a severe course of COVID-19. The mortality of hospitalized patients with COVID-19 above the age of 80 years is up to 54% in international studies. These observations indicate the necessity to highlight the geriatric perspective on this disease. The diagnostics and treatment of COVID-19 do not differ between younger and older patients but atypical symptoms should be expected more frequently in old age. Older subjects show an increased need for rehabilitation after COVID-19. Paradoxically, increasing rehabilitation demands go along with a reduced availability of geriatric rehabilitation options, the latter being a consequence of closure or downsizing of rehabilitation departments during the pandemic. In general, measures of isolation and quarantine should be diligently balanced as the health and emotional consequences of such measures may be severe in older persons. In light of the poor prognosis of older COVID-19 patients, advanced care planning becomes even more relevant. Caregivers and physicians should be encouraged to compose advanced care directives that also reflect the specific circumstances of COVID-19. Fortunately, current data suggest that the effectiveness of the vaccination with the mRNA-vaccines approved in Germany may be equally high in older compared to younger persons.

Design and Implementation of a Skilled Nursing Facility COVID-19 Unit

Coronavirus disease 2019 (COVID-19) has challenged the health care system's capacity to care for acutely ill patients. In a collaborative partnership between a health system and a skilled nursing facility (SNF), we developed and implemented an SNF COVID-19 unit to allow expedited hospital discharge of COVID-positive older adults who are clinically improving, and to provide an alternative to hospitalization for those who require SNF care but do not require or necessarily desire aggressive disease-modifying interventions.