EXPRESSO: EXploring the PREvalence, Service utilisation and patient experience of Severe Obesity

Williamson, Kath (2023) EXPRESSO: EXploring the PREvalence, Service utilisation and patient experience of Severe Obesity. PhD thesis, University of Glasgow.

Full text available as:
[thumbnail of 2023WilliamsonKPhD.pdf] PDF
Download (3MB)


The study’s genesis is the author’s district nursing role caring for increasing numbers of individuals at home with severe obesity (BMI ≥40 kg/m2 ). Such individuals often experience physical disability and functional limitations associated with severe obesity, needing help at home from community health and social care services. Care needs can pose previously unknown challenges for care providers. Little evidence exists to guide quality of care, service development or effective use of resources.

To better characterise the population with BMI ≥40 kg/m2 who require help at home from community health and social care services.

Key questions are:
1. How many people known to health and social care services have a current BMI ≥40 kg/m2 ?
2. How many of these are known to be housebound or in care?
3. What health and social care services does the BMI ≥40 kg/m2 population use?
4. What are the costs of these health and social care services?
5. What are participants’ experiences of using these services?

A scoping review of international measured prevalence data on adult BMI ≥40 kg/m2 applied a broad search strategy, utilising diverse sources.

An instrumental case study approach was used to explore the approvals process for this mixed-methods, observational study, engaging routinely-collected data. In a representative United Kingdom local authority, consenting individuals with severe obesity were recruited via community health and social care professionals. Participants were visited at home by the investigator, where height and weight measures were taken using specialist weighing scales and alternative height measures where needed.

An investigator-administered questionnaire recorded participants’ self-reported need for help at home, including use of community health and social care services. Data were verified against routinely-collected data in health and social care records. Local and published sources informed a detailed micro-costing. Community services were also asked to identify eligible adults in a “census” of their caseloads.

A nested qualitative element involved participants undertaking individual, audiorecorded, semi-structured interviews, which were transcribed and analysed using reflexive thematic analysis.

Eighteen countries, across five continents, reported BMI ≥40 kg/m2 prevalence data in surveys since 2010: 11% of eligible national surveys examined. Prevalence
of BMI ≥40 kg/m2 ranged from 1.3% (Spain) to 7.7% (USA) for all adults, 0.7% (Serbia) to 5.6% (USA) for men and 1.8% (Poland) to 9.7% (USA) for women. Limited trend data covering recent decades support significant growth of the population with BMI ≥40 kg/m2.

Formal approvals by nine separate stakeholders from four different organisations took nearly three years, including fifteen initial or revised applications, assessments, or agreements. Fragmented data systems, multiple data controllers, and a changing data governance environment created challenges to using routine data, requiring study design modification.

Twenty-five individuals (15 women) participated, aged 40-87 (mean=62) years, BMI 40-77 (mean=55) kg/m2 : 20 participants (80%) were housebound. Incomplete census data identified a further 261 eligible individuals.

Weights ranged from 98.4 to 211.8 kg (mean=150 kg), with 16 participants requiring bariatric scales. For six people unable to stand, wheelchair scales(n=1), bed weighing scales (n=2),
routine weights from care home records (n=2) or weight data from hospital records (n=1) were used. The standard portable stadiometer was usable for only one participant: Others required alternative measures from which to estimate height, which gave diverse heights.

Twenty-two different cross-sector community health and social care services were used. Only five participants had contact with weight management services. Twenty-four (96%) participants used three or more services, with longest care episode lasting over 14 years. Total annual service costs incurred by participants varied from £2,053 to £82,792 base case estimate, mean £26,594 (lower estimate £2,053 to £80,064, mean £22,462; upper estimate £2,053 to £88,870, mean £30,726), with greatest costs being for social care.

Nine women and three men (n=12) participated in qualitative interviews, aged 40-76 (mean 60) years, BMI ranged from 45-74 (mean 59) kg/m2 , eight were housebound. Three overarching themes were identified. Firstly, the hidden struggles of living with a larger body impacted all participants, including functional limitations affecting mobility and personal care. These contributed to a sense of being stuck physically, socially, and biographically, partially due to poor treatment options. A second theme found explicit weight bias was commonly, but not wholly, denied. However, most participants related implicit weight bias by a system structurally unprepared to care for people with severe obesity. The majority of participants showed strong internalised weight bias, linked to shame and self-blame for their poor function and larger bodies. Thirdly, a day-to-day coping theme highlighted strategies regularly used by participants: resigned acceptance, avoidance and denial, exercising choice, and support from informal carers.

Accurate prevalence data for the population with BMI ≥40 kg/m2 is under reported. International health surveys could improve data availability by publishing disaggregated data beyond BMI ≥30 kg/m2 . Current practice regarding anthropometric measures likely excludes people with severe obesity and functional limitations. Specialist scales and standardised methods for height estimation appropriate for people with severe obesity are needed. Lack of data impairs surveillance of population trends, understanding of causation, societal provision for individuals living with higher weights, and the effectiveness of future service planning.

Practitioners face a complex approvals process to use data they routinely collect for research or evaluation purposes. Data sources for poorly documented community health and social care services exist and are navigable at an individual level. Population-level usage of such records needs developed.

Adults with severe obesity, including those under 65 years, may need sustained care from multiple community care services, with potentially high annual costs. Economic evaluations of obesity and weight management need to include these wider care costs to ensure completeness.

Participants experienced unmet physical and psychological care needs associated with their larger bodies, leading to poor quality of care and life. Given rising prevalence, changes to care services are required. Specific recommendations include staff training about needs of people with severe obesity, ensuring the physical infrastructure of care services can safely accommodate people with severe obesity, and improving access to effective, person-centred weight management treatments, with strategies to tackle internalised weight bias.

Future research could explore how the duration and severity of obesity affects an individual’s functional limitations, subsequent need for care, and quality of life.

Item Type: Thesis (PhD)
Qualification Level: Doctoral
Subjects: R Medicine > RA Public aspects of medicine
R Medicine > RT Nursing
Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
Supervisor's Name: Lean, Professor Michael
Date of Award: 2023
Depositing User: Theses Team
Unique ID: glathesis:2023-83732
Copyright: Copyright of this thesis is held by the author.
Date Deposited: 24 Jul 2023 07:48
Last Modified: 24 Jul 2023 07:51
Thesis DOI: 10.5525/gla.thesis.83732
Related URLs:

Actions (login required)

View Item View Item


Downloads per month over past year