Could living with an anxious partner reduce your own life expectancy?
Studying Zebra finches, Taeniopygia Guttata, researchers from the University of Glasgow saw that when glucocorticoid stress hormones were elevated early in life, the birds exhibited increased stress sensitivity in adult life and a reduced lifespan as a result. More significantly, the researchers noted that breeding partners of these birds also experienced decreased life expectancy and the trait seemed to apply to subsequent partners.
In the study, published in the journal Proceedings of the Royal Society B, 68 birds were fed the stress hormone (CORT) in peanut oil five days after hatching and compared with a control group of 90 birds that were only given the oil. CORT was fed to the birds for up to a month, before being withdrawn.
The group then looked at the survival rates of both groups for the following three years. The results were startling. 5% of birds in a control group died after three years, as opposed to 40% in the 'early stress' group, with most deaths occurring in the third year.
Although reproductive ability seemed unaffected, stress seemed to detrimentally affect sexual 'attractiveness'. Control birds were less likely to mate with CORT birds.
More significantly, those control birds that did mate with CORT-fed birds tended to die earlier too. Scientists suggested that the most likely explanation for this was that exposure to a stressed bird created a similar response in its breeding partner.
The research poses two poignant questions: could stress be contagious? And, could similar mechanisms be at work in humans?
Research tells us that stress can and does adversely affect health. Children who experience a stressful childhood are known to be more stress-sensitive in later life. And most people who have lived with a 'stressed-out' partner will experience higher stress levels themselves as a result of that relationship.
Certainly, more work needs to be done on the effects of sharing daily life with a stressed partner, but the evidence is there to suggest that there could be a detrimental affect on your own health and perhaps even your lifespan.
Top Image Credit: Male zebra finch © Kodo34