Outcomes of elderly patients admitted to intensive care unit and their association with frailty scores  a cohort study

Background

With increase in the survival age in the last 100 years number and proportion of elderly patients admitted to ICU has increased and so has the patients diagnosed with frailty The average global population aged 65 years is currently close to 85 and is expected to be nearly 16 by 2050 Global estimates of frailty range from 35 to 27 In India incidence of frailty is between 1540 in the hospitals caring for older adults 1 Assessment of morbidities among elderly patients admitted to ICU the diagnosis of frailty and their course in the hospital has implications for assignment of resources in the hospital as well as the communities On literature review we found only one prospective registryembedded cohort study 2 on the outcomes of elderly patients admitted to Indian ICUs Hence we would like to conduct this cohort study where elderly patients defined chronologically by age above 65 years will be included in the study They would be assessed for presence of frailty using Clinical frailty score CFS 3 which is the commonest frailty score used in the ICU 4 They will be followed up for hospital outcomes and escalation of care until discharge The primary aim of this study is to describe the epidemiology of elderly ICU patients We would also like to compare the outcomes between elderly frail and nonfrail patients 

Methodology

This will be a prospective observational multicentre study on the cohort of elderly patients admitted to the ICU We expect the study duration to be around two years No treatment modifications will be made based on the CFS assignment of these elderly patients All patients admitted to ICU aged 65 years will be assessed for frailty using the Rockford frailty scores also known as clinical frailty score CFS 3 CFS will be assigned at the participating ICUs based on the history from the patient or the relative Study coordinators will be identified at every participating centres and online training will be provided on the assignment of CFS using the examples and standard image templates Baseline comorbidities of included patients will be recorded Their medication history will be recorded All patient related information will be entered into the online patient information database Indian Registry of Intensive Care  IRIS Maintaining confidentiality and data protection of all the patient related information will be as per the security protocol managed by the IRIS platform

Our primary outcome will be hospital mortality The secondary outcomes will be Length of stay LOS in ICU readmission to ICU hospital LOS escalation of care events including  renal replacement therapy RRT vasopressorsinotropes invasive mechanical ventilation and others

Inclusion criteria

Elderly patients above 65 years of age admitted to ICU

Exclusion criteria

1 No legal guardian available to give consent

2 Refusal of consent

Statistical analyses 

The enrolled patients will be classified into CFS 14 Very fit to vulnerable defined as nonfrail vs CFS 58 mild Frailty to very severe frailty defined as frail for the purpose of analysis Based on survey of previous literature 2 for an outcome variable on mortality rate in two groups of patients in ICU with minimum difference of 50  to attain significance at type I error   error of at least 5 Type II error  error of 10 and keeping statistical power above 90 the estimated sample size is 900 for two  group assessment clinical study after adjusting for losttofollow up dropout rates and withdrawal of consent 5 The data collection will be carried out until the predetermined sample size is reached The statistical methods ChiSquare test Fisher exact test student t test or any other suitable method will be employed at the time of data analysis as appropriate

References

1 Chatterjee P Understanding Frailty The Science and Beyond in Health and Wellbeing in Late Life Perspectives and Narratives from India ed Chatterjee P 120

2 Tirupakuzhi Vijayaraghavan BK Rashan A Ranganathan L Venkataraman R Tripathy S Jayakumar D et al IRIS collaborative Prevalence of frailty and association with patient centered outcomes A prospective registryembedded cohort study from India J Crit Care 2024 Apr80154509 

3 Rockwood K Song X MacKnight C et alA global clinical measure of fitness and frailty in elderly people CMAJ 2005 173 489495

4 Darvall JN Bellomo R Paul E Subramaniam A Santamaria JD Bagshaw SM Rai S Hubbard RE and Pilcher D 2019 Frailty in very old critically ill patients in Australia and New Zealand a populationbased cohort study Med J Aust 211 318323