Older adults with insomnia have an altered immune response to stress that increases levels of interlukin 6 up to 4 fold, which may increase the risk of illness and death. In this study that was published in February of 2012 in the American Journal of Geriatric Psychiatry, there were 83 people with an average age of 61. Twenty seven percent were poor sleepers. Stress led to a much larger increase in IL-6 in poor sleepers than in good sleepers. It appears that poor sleep in combination with stress leads to an exaggerated stress response.
The fact that there was more depression, loneliness, and more global perceived stress in the group with poor sleep, did not in itself show a difference in IL-6 levels prior to the added stress of a series of tests of verbal and working memory.
It is imporant to find the underlying cause for insomnia and resolve it using cognitive or somatic therapies if we're going to avoid the added inflammation caused by additional stress. We also know that using hypnotics is associated with increase mortality and with increased risk of cancer!