"During the difficult weeks and months after loss we can suffer from reduced neutrophil function. Neutrophils are the most abundant type of white blood cell and as such are essential at combating infections and illnesses, so we become vulnerable when this happens," she said.
The damaging impact of grief on the immune system could be traced to the disruption in the balance of two hormones, cortisol and dehydroepiandrosterone sulphate (DHEAS), which are involved in coping with stress.
In younger people the proportion of the two hormones remained balanced after the death of a loved one, while in bereaved, elderly individuals the levels of cortisol were relatively high compared to the low levels of DHEAS.
DHEAS is known to counteract the harmful effects of cortisol in times of stress and protect the immune system, and its level declines with age.
"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," said Professor Janet Lord, also from the University of Birmingham, a co-researcher on the study.
"But 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," Professor Lord said.
Reference and acknowledgement---
http://timesofindia.indiatimes.com/Home/Science/Why-the-elderly-can-go-downhill-after-the-loss-of-their-partner/articleshow/42223859.cms