Stress and immunity
Investigator
Janet Lord, Birmingham University
Team
Anna C Phillips, Birmingham University
Jan Oyebode, Birmingham University
Wiebke Arlt, Birmingham University
Catherine Sackley, Birmingham University
Doug Carroll, Birmingham University
Glyn Humphreys, Birmingham University
Keith Porter, University Hospital Birmingham Foundation NHS Trust
Partners and collaborators
Help the Aged - Age Concern
The National Coallition on Active Ageing
The Birmingham 1000 Elders Group
Background
For many seniors, the conversion from being a healthy older adult to one in frail physical or mental health can be sudden, with falls representing a key cause of increased morbidity and mortality.
Almost one in three people over 65 will fall at least once a year. Hip fracture is a frequent consequence of a fall and is a catastrophic event that happens to approximately 86,000 older people in the UK each year.
Fracture is associated with poor outcome, approximately one third of patients are dead at one year post fracture and one quarter enter institutionalisation at discharge. Few regain pre-fall levels of quality of life.
It is well established that our immune system declines with age and post-operative chest infections are the major six month mortality risk factor in hip-fracture patients, with pneumonia the cause of death in 43% of patients.
Physical trauma, such as a fall, is thus a major risk for progression to frailty in seniors and reduced immunity is a key underlying frailty factor. If we are to improve quality of life for older people, understanding how falls and hip fractures can lead to frailty and how we might intervene to maintain health after hip fracture, is imperative.
Depression is also associated with increased susceptibility to infectious disease, with reduced immune cell function. Furthermore, depression is in 30% of hip fracture patients and symptoms of depression in patients with hip fracture hold considerable implications for prognosis.
Depression has been associated with greater pain persistence, retarded recovery and higher mortality rates. Depression coincident with the physical trauma of hip fracture may therefore accelerate progression from health to frailty via a negative impact upon immunity.
A key question that remains to be addressed, and which has great significance for the health and quality of life of seniors after falls and hip fracture, is therefore whether depression and physical trauma synergise to accelerate ageing of the immune system.
Finally, there is an important and often neglected additional factor that can influence how quickly and how well an older person recovers from illness, namely the beliefs and meanings (ie, the illness representations) he/she attaches to the illness. There is evidence that minority cultural groups hold illness representations that differ in various respects from the majority in the UK.
Studies of the perception of age-associated dementia amongst British people of Punjabi Indian origin has revealed that symptoms of dementia were thought to partly result from a lack of effort by the patient themselves. Extending such studies to consider attitudes to hip fracture will address this issue in a significant minority ethnic patient grouping in the UK.
Aims and objectives
The overall aim of this study was to determine whether ageing, physical stress (hip fracture) and psychological stress (depression) are key and interacting factors influencing immune frailty in seniors.
It was also important to determine whether the negative cumulative effects of these stressors extend beyond immune frailty and lead to cognitive and physical frailty.
The study additionally determined whether or not illness representations affect quality of life for hip fracture patients in a minority ethnic group.
Design
The study had a three year prospective case-control design with four groups of female seniors:
50 British white hip fracture patients with, or without depression
30 British patients of Punjabi Indian ethnicity with hip fracture but no depression and 50 healthy seniors.
Patients were assessed one and six months after hip fracture to determine the short and long term effects of the trauma.
To assess the combined impact of hip fracture and depression immunity: We assessed innate immune function and the immune risk phenotype in older adults with or without hip-fracture and with or without depression.
Examine the role of hormones: We measured levels of stress hormones (cortisol; DHEAS) to determine their role in mediating the negative effects of depression and hip fracture upon immunity and wider aspects of frailty.
Examine the link between immune frailty and physical and mental frailty: A stress may also affect other aspects of frailty such as physical and mental frailty and these were assessed at six months post-fracture.
Determine whether illness representations differ between hip fracture patients of British white and Punjabi Indian ethnicity: If minority ethnic groups hold different illness representations for hip-fracture this may affect their recovery from illness and this was determined in a pilot study as part of the overall project.
Outcomes
The project outcomes:
Publications in peer-reviewed medical science journals, ensuring communication of the key findings of the project.
An information pamphlet for health and social care professionals to ensure the key findings of the project with regard to the impact of depression on outcome for hip-fracture patients is communicated.
Strengthened links with stakeholders and researchers nationally.
An interdisciplinary research team able to take forward their findings on the impact of stress on health in old age.
Policy implications
This project had a range of policy impacts, mainly in the area of rehabilitation practices for hip-fracture patients.
Key policy and/or practice implications of the research
Policy and practice implications focussed primarily on considering whether interventions to reduce depression in hip-fracture patients will improve prognosis, specifically whether this could lead to a reduction in life-threatening infections in the months following the fracture.
These included:
Raising awareness of the impact of depression upon immunity and recovery from hip-fracture amongst health-care professionals, patients and carers.
Providing examples of best self-help practice for older people with symptoms of depression following hip-fracture.
Providing advice to older people and to health care professionals about the importance of treating depression in hip-fracture patients.
Providing an evidence base for the pharmacological treatment of depression following hip-fracture.
The project could also have impact upon rehabilitation practices of ethnic minority patients if differences in illness representations are found in the British Punjabi group of patients. A follow up study would however be required to determine if the illness representations of this group had a positive or negative impact upon their recovery from hip-fracture.
Key non-academic user groups that were targeted
Older people with hip-fracture and their carers
Charities and other organisations representing older people, both living in the community and in care homes
Health care professionals - " Primary Care Trusts, nurses, health and social care staff
Educators and trainers of health and social care professionals
Community groups based in the British Punjabi population
Assistance needed from the NDA programme in this targeting
A high corporate and political profile for the overall NDA programme facilitated maximisation of the policy and practice impact of the project.
Targeted press releases and promotion of findings to a wide range of non-user groups.
Facilitation of contacts with non-academic user groups.
Support to develop and produce targeted user-friendly information and recommendations in hard copy and on the web.