Childhood maltreatment and leukocyte telomere length: Cardiac vagal activity influences the relation in older adults

Abstract

Abstract Objective Childhood maltreatment is associated with shorter leukocyte telomere length (LTL). However, the influence of cardiac vagal control on this relation is unknown. We examined whether cardiac vagal control at rest and in response to stress moderates or cross-sectionally mediates the relationship between childhood maltreatment and LTL. Methods Participants were 1179 men and women (aged 65 ± 7.2 years) suffering from coronary artery disease (CAD) or non-cardiovascular chronic disease. They completed a childhood maltreatment questionnaire and underwent a stress protocol while ECG was monitored. HF-HRV measures were obtained at rest, during stress, and post-stress in absolute and normalized units (nu). LTL was measured using qPCR. Mediation and moderation analyses were performed. Results HF-HRV and HFnu measures did not mediate the childhood maltreatment-LTL relation. However, baseline HFnu (p = .027) and HFnu reactivity (p = .051) moderated the relation. Specifically, maltreatment was associated with significantly lower LTL among those with baseline HFnu at (b = -.059, p = .003) or below the mean (b = -.103, p < .001), but not among those with higher baseline HFnu. It was also associated with significantly lower LTL among participants who showed either blunted (b = -.058, p = .004) or increased HFnu (b = -.099, p = .001) responses to stress but not in those with large decreases in HFnu. Conclusions Childhood maltreatment was associated with lower LTL in those who showed a distinct cardiac vagal profile at baseline and in response to stress. The mechanisms and implications remain to be determined.