Bereavement affects a person’s immune system, and the impact varies as we grow older, say researchers.
“During the difficult weeks and months after loss we can suffer from reduced neutrophil function,” said Dr. Anna Phillips of Birmingham University, U.K.
“Neutrophils are the most abundant type of white blood cell and as such are essential at combating infections and illness, so we become vulnerable when this happens.”
Her research is the first to investigate the links between stress hormones and immune function across different ages. It looked at participants who were grieving for the loss of either a spouse or close family member. Taking part were 41 young adults, with a mean age of 32 years, and 52 older adults, with a mean age of 72 years.
Results showed that as we age, the balance of so-called “stress hormones” during grief alters, putting the elderly at greater risk of reduced immune function and consequent infections. The young bereaved participants showed “robust neutrophil function,” whereas it was reduced among the older bereaved participants.
Specifically, the hormones cortisol and dehydroepiandrosterone sulphate (DHEAS) respond differently to loss as we age. This has a negative impact on neutrophil function.
In younger people, the ratio of cortisol and DHEAS was more balanced, whereas cortisol was significantly higher than DHEAS among older participants. This is a hormone with known immune-suppressive effects. DHEAS, while also secreted by the adrenal gland in response to stress, is thought to be immune-enhancing.
This study is published in the journal Immunity and Ageing.
“The effects of loss are poorly understood on the whole, we know that it affects the immune system amongst other things, but we don’t fully understand the role played by our stress hormones,” said Phillips.
“We hope that this is a step towards that understanding, and being able to provide the best possible support.”
The team suggests that younger people show no detrimental effect of bereavement on neutrophils due to “the absence of immunosenescence and adrenopause in this younger aged bereaved group.” Immunosenescence is the gradual deterioration of the immune system over the lifetime, and adrenopause is the gradual slowing of adrenal gland activity.
Co-author Janet Lord, Ph.D., pointed out, “Cortisol is known to suppress elements of the immune system during times of high stress, so having an unbalanced ratio of cortisol and DHEAS is going to affect how able we are to ward off illness and infection when grieving.
“But, of course, it is also incredibly useful, particularly in activating some anti-stress and anti-inflammation pathways, so it’s not as simple as trying to suppress the cortisol in vulnerable people.”
However, hormonal supplements or similar products may prove to be useful for people at an increased risk. Once we know more about the changing ratio of these hormones, researchers can test whether altering the balance artificially could be a short-term help, believes Phillips.
But she added, “However, there is quite simply no substitute for a strong support network of family and friends to help manage the risks during a period of grieving.”
Further studies have suggested that sources of stress besides bereavement may have a more detrimental impact on the immune system as we age. Studies of older spouse caregivers for partners with dementia have found clear evidence of compromised immune function. Findings on younger caregivers have come up with more variable results.
Studies of hip fracture have shown impaired immune function specifically in older adults, and not in young patients with similar injuries. It affected the cortisol:DHEAS ratio most negatively among older patients with depressive symptoms compared with those without depression.
“These data suggest that the effects of some types of stress on immunity may only be observed among older adults, or among those with poorer psychological status, e.g., high depressive symptoms,” write Phillips and colleagues.
In fact, there is accumulating evidence that stress and age are interactive, with chronic stress exacerbating the immune effects of aging. In one study, lower marital satisfaction in older adults was linked to less effective antibody responses to vaccination. The same study showed that bereavement was also associated with a worse antibody response to vaccination.
The death of a loved one is one of life’s greatest stresses, with reports of increased mortality and illness especially in the early months. Research to date suggests that bereavement is associated with a range of damaging physiological changes.
In summary, it seems that the stress of bereavement exaggerates the age-related decline in immune function, which may help to explain the increased risk of infection in bereaved older adults.
Vitlic, A. et al. Bereavement reduces neutrophil oxidative burst only in older adults: role of the HPA axis and immunesenescence. Immunity & Ageing, 10 September 2014 doi:10.1186/1742-4933-11-13