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HoW-CGA: Comprehensive geriatric assessment for frail older people in acute hospitals

The aim of the Hospital Wide Comprehensive Geriatric Assessment (HoW CGA) project was to inform NHS managers, clinicians, patients and the public about how best to organise hospital services for frail older people.

Published: 10 March 2021



The aim of  the Hospital Wide Comprehensive Geriatric Assessment (HoW CGA) project was to inform NHS managers, clinicians, patients and the public about how best to organise hospital services for frail older people.

There is considerable evidence on how to assess and coordinate care for frail older patients with complex needs using Comprehensive Geriatric Assessment (CGA). Comprehensive geriatric assessment is defined as ‘a multidimensional, interdisciplinary diagnostic process to determine the medical, psychological, and functional capabilities of a frail older person in order to develop a coordinated and integrated plan for treatment and long-term follow-up’. CGA improves outcomes for frail older people, including survival, cognition, quality of life and reduced length of stay, readmission rates, long term care use and costs.

There is continued uncertainty about how to target suitable recipients in a hospital wide manner, and what is the most appropriate and cost-effective form of CGA for different settings.

Key features

  • Design - mixed-methods study combining a mapping review, national survey, large data analysis and qualitative methods
  • Participants - people aged above 65 years in acute hospital settings
  • Chief Investigator - Professor Simon Conroy, Professor of Geriatric Medicine, University of Leicester.

Aim of the study

The overarching aim of this programme of work was to provide high quality evidence to support the delivery of CGA on a hospital wide basis by:

  • defining CGA, its processes, outcomes and costs in the published literature
  • identifying the processes, outcomes and costs of CGA in existing hospital settings in the UK
  • identifying the characteristics of the recipients and beneficiaries of CGA in existing hospital settings in the UK
  • using this new knowledge to develop tools that will assist in the implementation of hospital-wide CGA.

Study team approach

Four workstreams were established:

Defining CGA

This workstream carried out a systematic literature review of articles that described the provision of CGA in hospital patients.

Identifying CGA

A national survey was developed by a multidisciplinary team (MDT) and included questions informed by the literature review and a related community study. The survey was piloted and validated, then refined through a series of interviews. An NHS trust survey asked about the provision of acute care and was sent to each chief executive officer. The response to this indicated who should be contacted to complete the online service survey about care delivery.

Characterising beneficiaries

This workstream lead on a large data analyses which included:

  • looking at past hospital activity patterns to see if people aged over 75 could be categorised according to hospital care use
  • cluster analysis on anonymised patient level Hospital Episode Statistics (HES) data of people over 75 who were discharged from hospital between 1 April 2014 and 31 March 2015 excluding those discharged from mental health and community hospitals
  • creating a clustering matrix that could be used to group patients. The matrix compared their diagnoses, number of bed-days and hospital costs
  • a hospital frailty risk score with three categories; low, intermediate and high risk
  • the frailty risk score was tested against a data set from 1,013,590 people aged over 75 who were admitted to hospital emergency departments between 1 April 2014 and 31 March 2015
  • looked at the key costs incurred by the CGA such as staff, training,equipment, overheads through interviews, site visits and a survey.

Developing implementation tools

This workstream developed a CGA toolkit based on finding of the project so far and was tested in three services providing pre-operative assessment of older people who had cancer or who were awaiting vascular surgery. Data collection from the testing came via observation and interviews.

Outcomes and findings

Older people in acute hospitals are at high risk of poor outcomes, which can be improved through the delivery of specialist geriatric care in dedicated ward areas. The optimal method by which to deliver such care across the whole hospital is unclear. Current service provision is patchy, poorly standardised and, in surgical and oncology settings, does not usually involve teams specialised in older people’s care.

A frailty risk score derived from routine data was tested in over 1 million patients. Those with a high frailty risk had 70% higher odds of inpatient mortality, six times the odds of a prolonged stay and 50% increased odds of emergency readmission within 30 days. 

Clinical toolkits designed to empower non-geriatric teams to deliver CGA were received with initial enthusiasm but did not fully achieve their stated aims owing to the need for an extended period of service development with geriatrician support and to competing priorities.

Outcomes from this project include a tool to allow frailty to be identified across the whole country using routine hospital data, easy-to-use spreadsheets that can inform hospitals and local authorities about the nature of frailty in the populations for whom they care and a toolkit that is ready for further testing within specialist services.

Implications for health systems

Much of the evidence for CGA indicates that it is most effective when applied in discrete ward settings or specialised units. The aim of this research was to ascertain how best to identify frailty in acute hospital settings and to develop tools to help clinicians, service managers and commissioners deliver CGA for older people with frailty who are not on discrete wards.

The HoW CGA study’s literature review summarised the extensive evidence base for CGA and helped the study team to characterise new and emerging services that are beginning to deliver CGA on a hospital-wide basis.

Other studies looking at the use of CGA in acute hospital care to date have not usually selected older people for intervention using frailty risk tools as now defined. Rather, according to the conventions of their times, the early trials mostly selected people on the basis of age, with many studies using lower cut-off points of 60 or 65 years. In addition, they have tended to focus on clinical and operational outcomes that matter to clinicians and researchers rather than outcomes that matter to patients.

The study team identified a number of types of service that are beginning to deliver CGA where it has not traditionally been found, such as oncology, emergency medicine and perioperative care. However, the evidence base in these areas is still rather rudimentary and does not provide clear insights into the best ways to spread CGA across the whole hospital.

Many frail older people receive their acute hospital care in general medical settings. Although clinicians in this setting typically possess many of the competencies to care for older people with frailty, the study’s survey findings suggest that there is significant variability in the delivery of frailty adapted care.

Interventions aimed at enhancing the clinical skills, and particularly the organisational elements of care in this setting, are likely to be more feasible and potentially to have a greater impact e.g. in a hospital admitting 1000 older people per month, around 200 would be classified as severely frail, in whom the application of CGA might result in 12 more people being alive and in their own home, and 40 fewer people being admitted to long-term care.

Other findings and future ambitions

  • The evaluation of pilot sites’ efforts to incorporate CGA into their work showed only limited progress during the study period. In part, this was because of the sheer volume of work involved in such an important change, as well as the interaction with existing procedures, policies and timelines
  • A good history of multidisciplinary collaboration did not guarantee smooth incorporation of the principles of CGA into routine practice
  • Surgical teams felt a strong need to include geriatricians in direct clinical care, as well as service design. There are insufficient geriatricians to manage all frail older people and this gap will widen as population ageing continues to increase
  • The study team has the opportunity to test the HoW-CGA toolkit in other specialised services (renal dialysis, chemotherapy, emergency cranial neurosurgery, interventional cardiology, complex spinal surgery and adult critical care) as part of work commissioned by NHS England, which started in 2019. For some of these specialist areas (neurosurgery, interventional cardiology, complex spinal surgery), it would be surprising if the outcomes will be vastly different from those seen so far. Others might be more attuned to interacting with frailty (renal haemodialysis and critical care); it will be important to evaluate this further iteration of the HoW-CGA toolkit.

Chief Investigator Professor Simon Conroy

“Comprehensive Geriatric Assessment remains the gold standard approach to improving a range of outcomes for older people in acute hospitals. The Hospital Wide Comprehensive Geriatric Assessment study found that toolkits aimed at enhancing the delivery of CGA by non-specialists can be useful but require prolonged geriatrician support and implementation phases. Future studies could consider comparing the hospital-based frailty index with the electronic frailty Index and further testing of the clinical toolkits in specialist services.”

Key publications

Conroy SP, Bardsley M, Smith P, Neuburger J, Keeble E, Arora S, et al. Comprehensive geriatric assessment for frail older people in acute hospitals: the HoW-CGA mixed-methods study. Health Serv Deliv Res 2019;7(15).


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