Relationships between stress perception and stress biomarkers in family caregivers

Background: Family caregivers (FCGs) of persons with dementia (PWDs) face chronic stress. However, their stress has often been assessed by their distress in the absence of physiological indicators. Studies to date have rarely documented the relationships between distress and various stress biomarkers. Purpose: The aim of this study was to explore the relationships between distress and stress biomarkers in FCGs. Methods: This was a secondary data analysis study that used data collected by two projects funded by the National Science Council. Samples included 113 dyads of PWDs and their FCGs willing to donate blood samples. Original study data sites comprised two teaching hospitals (memory clinics and psychiatric outpatients), two regional hospitals (neurology clinics), and two dementia daycare centers for community-dwelling PWDs in northern Taiwan. FCG distress was assessed using the Chinese Neuropsychological Inventory-Caregiver Distress Scale (CNPI-CD); Stress biomarkers included interleukin (IL)-1β, IL-6, IL-10, cortisol, and C-reactive protein (CRP). Results: Stress biomarker levels did not correlate with overall FCG distress related to PWD neuropsychological problems. However, IL-1ß, IL-6, and IL-10 levels did correlate with specific FCG distress toward specific PWD neuropsychological symptoms. Conclusions: This study found certain stress biomarkers (IL-1ß, IL-6, IL-10) associated with specific PWDs' neuropsychological symptoms (p <.05). Further longitudinal research is needed to clarify causal relationships between subjective distress and objective stress biomarkers to evaluate FCG stress levels more comprehensively.