Association between serum trace elements and sleep disturbance in patients with decompensated cirrhosis

Abstract

Background: Sleep disturbance and trace elements imbalance are common features in patients with decompensated cirrhosis, partially sharing similar mechanistic contributors and linking to adverse outcomes. However, there is a paucity of data concerning their relationship.

Objectives: To investigate the association between serum trace elements levels and sleep quality in the context of cirrhosis.

Design: Cross-sectional study.

Methods: We consecutively enrolled 160 patients with decompensated cirrhosis. The sleep disturbance was determined by the Pittsburgh Sleep Quality Index (PSQI > 5). Serum trace elements [magnesium, calcium, iron, copper (Cu), zinc (Zn), lead, and manganese] was measured by inductively coupled plasma mass spectrometry. Association of examined trace elements levels and sleep disturbance was analyzed by multiple linear (global PSQI scores) and multivariate logistic (dichotomized PSQI categories) regression models, respectively.

Results: In total, 91 patients (56.88%) represented PSQI-defined sleep disturbance, characterized by female preponderance, lower body mass index levels, and higher serum Cu levels (all p < 0.05). Looking into its clinical relevance with debilitating conditions, we showed that Cu/Zn ratio (CZr) is significantly higher in cirrhosis with poor sleep quality (1.77 versus 1.48, p = 0.003). Diagnostic performance analysis indicated CZr > 1.62 to exhibit better discrimination relative to respective Cu. Both multiple linear (β = 0.355, p < 0.001) and multivariate logistic regression (odds ratio = 2.364, p = 0.019) identified higher CZr as an independent risk factor associated with sleep disturbance.

Conclusion: Our findings implied an association between higher CZr and the presence of sleep disturbance in patients with decompensated cirrhosis.

Keywords: Cu/Zn ratio; PSQI; liver cirrhosis; sleep disturbance; trace element.

Figure 1.

ROC analysis of serum CZr levels for classifying sleep disturbance in patients with decompensated cirrhosis. CZr, Cu/Zn ratio; ROC, receiver operating characteristics.

Figure 2.

Correlation analysis between serum Cu levels and PSQI scores in the overall population (a), poor sleepers (b), and good sleepers (c). In addition, correlation analysis between CZr and PSQI scores in the overall population (d), poor sleepers (e), and good sleepers (f). Cu, copper; CZr, Cu/Zn ratio; PSQI, Pittsburgh Sleep Quality Index.