Caregiving for allogeneic hematopoietic stem cell transplant (Allo-HSCT) patients carries a significant psychological burden, yet it remains unclear whether Allo-HSCT caregivers demonstrate disruptions to stress systems, such as the hypothalamic-pituitary-adrenal axis. Greater intraindividual cortisol variability (ICV) has been observed in psychiatric disorders; however, there is a knowledge gap evaluating ICV in caregivers. We predicted that greater ICV would be related to poorer mental health in Allo-HSCT caregivers.Methods
Allo-HSCT caregivers (n = 140) collected saliva for 3 consecutive days at 4 time points/d. Psychological variables included sleep quality and a summary composite score of overall mental health.Results
Regression analyses demonstrated that greater ICV was significantly related to poorer overall mental health (β = 0.25, p = .009), whereas poorer sleep did not reach significance (β = 0.16, p = .069). No significant relationships emerged for the cortisol area under the curve, diurnal decline, or awakening response.Conclusions
Results extend prior work examining ICV as a unique marker that is possibly more sensitive than other widely applied measures of hypothalamic-pituitary-adrenal axis dysregulation to a distressed population of caregivers.