Factors associated with inflammatory cytokines in family caregivers of allogeneic hematopoietic stem cell transplantation (HSCT) recipients.

BACKGROUND

Family caregiving has been proposed as chronic stress that may lead to immune health risks through increased systemic inflammation. Cytokines are key modulators of inflammation via a complex network of interactions. However, most studies examined only a single to a few cytokines to determine whether they correlate with psychobehavioral variables of interest. This study aimed to investigate factors influencing multiple inflammatory cytokines in family caregivers of allogeneic hematopoietic stem cell transplantation (HSCT) recipients.

METHODS

Baseline data from a randomized controlled clinical trial at the National Institutes of Health Clinical Center were collected from caregivers of allogeneic HSCT recipients. The 20 serum cytokine levels were measured using multiplexed cytokine immunoassays. Multiple linear regression was conducted.

RESULTS

Caregivers (N = 45) were 44.6 ± 15.4 years of age; primarily female (87 %), White (66 %), non-Hispanic (82 %), and a spouse/partner of the HSCT recipient (56 %). Caring for HSCT recipients with hematologic malignancy predicted higher IL-12/IL-23p40 than caring for non-malignant HSCT recipients (β = 0.291, p = 0.044). Medication use was associated with higher IL-15 (β = 0.425, p = 0.017). Caregiver BMI overweight (β = 0.342, p = 0.043) or obese (β = 0.411, p = 0.010), taking prescribed medications (β = 0.521, p = 0.007), caregiving 8 to 16 h (β = 0.396, p = 0.027) or more than 16 h per day (β = 0.510, p = 0.006) predicted higher TNF-α than the counterparts.

DISCUSSION

These findings suggest inflammatory responses may be associated with providing care to an HSCT recipient, especially in caregivers who take medications, provide more hours of care a day and care for patients with hematologic malignancies. The results highlight a physiological response of stress and bring to light the importance of developing interventions focused on reducing time spent caregiving, such as a respite care program for family caregivers.