Topologically Disrupted Gray Matter Networks in Drug-Naïve Essential Tremor Patients With Poor Sleep Quality

Background

Sleep disturbances are widespread among patients with essential tremor (ET) and may have adverse effects on patients' quality of life. However, the pathophysiology underlying poor quality of sleep (QoS) in patients with ET remains unclear. Our study aimed to identify gray matter (GM) network alterations in the topological properties of structural MRI related to QoS in patients with ET.

Method

We enrolled 45 ET patients with poor QoS (SleET), 59 ET patients with normal QoS (NorET), and 66 healthy controls (HC), and they all underwent a three-dimensional T1-weighted MRI scan. We used a graph-theoretical approach to investigate the topological organization of GM morphological networks, and individual morphological brain networks were constructed according to the interregional similarity of GM volume distributions. Furthermore, we performed network-based statistics, and partial correlation analyses between topographic features and clinical characteristics were conducted.

Results

Global network organization was disrupted in patients with ET. Compared with the NorET group, the SleET group exhibited disrupted topological GM network organization with a shift toward randomization. Moreover, they showed altered nodal centralities in mainly the frontal, temporal, parietal, and cerebellar lobes. Morphological connection alterations within the default mode network (DMN), salience, and basal ganglia networks were observed in the SleET group and were generally more extensive than those in the NorET and HC groups. Alterations within the cerebello-thalamo-(cortical) network were only detected in the SleET group. The nodal degree of the left thalamus was negatively correlated with the Fahn-Tolosa-Marin Tremor Rating Scale score (r = −0.354, p =0.027).

Conclusion

Our findings suggest that potential complex interactions underlie tremor and sleep disruptions in patients with ET. Disruptions within the DMN and the cerebello-thalamo-(cortical) network may have a broader impact on sleep quality in patients with ET. Our results offer valuable insight into the neural mechanisms underlying poor QoS in patients with ET.

Socioeconomic Status in Pregnant Women and Sleep Quality During Pregnancy

This review focuses on factors contributing to sleep quality among pregnant women with low socioeconomic statuses during the third trimester of their pregnancy. Electronic searches were conducted, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We searched for published, peer reviewed, English language primary research articles using electronic databases including PubMed, EMBASE, Ovid, MEDLINE and Google Scholar ending June 2019. All references were reviewed manually and independently by authors. After applying the inclusion criteria, 56 articles were selected; 38 of which are full-text and included in this review. All articles related to the analysis of poor sleep quality among uncomplicated pregnant women were included. Pregnant women with a specific pathology were excluded.

We found poor sleep quality among pregnant women is correlated with low socioeconomic levels. Pregnant women with lower incomes tend to have inadequate diets, which further complicates the health of the mother and the baby. External factors including low income, poor quality of life and poor diet tend to increase the possibility of future health complications in both mother and child, and can result in complications such as preterm labor, low birth weight, preeclampsia, perinatal death, and spontaneous abortion.