Association Between Sleep Quality and Cognitive Symptoms in Patients with Major Depressive Disorder

Summary

Here, we present a protocol that investigates the relationship between cognitive symptoms and sleep quality in patients with major depressive disorder. The THINC-integrated tool and polysomnography were used to evaluate cognitive symptoms and sleep quality.

Abstract

Cognitive symptoms and sleep disturbance (SD) are common non-mood-related symptoms of major depressive disorder (MDD). In clinical practice, both cognitive symptoms and SD are related to MDD progression. However, there are only a few studies investigating the connection between cognitive symptoms and SD in patients with MDD, and only preliminary evidence suggests a significant association between cognitive symptoms and SD in patients with mood disorders. This study investigates the relationship between cognitive symptoms and sleep quality in patients with major depressive disorder. Patients (n = 20) with MDD were enrolled; their mean Hamilton Depression Scale-17 score was 21.95 (±2.76). Gold standard polysomnography (PSG) was used to assess sleep quality, and the validated THINC-integrated tool (the cognitive screening tool) was used to evaluate cognitive function in MDD patients. Overall, the results showed significant correlations between the cognitive screening tool's total score and sleep latency, wake-after-sleep onset, and sleep efficiency. These findings indicate that cognitive symptoms are associated with poor sleep quality among patients with MDD.

Introduction

Major depressive disorder (MDD), a serious mood disorder that causes significant morbidity and mortality, affects over 300 million people worldwide¹. MDD is characterized by low mood, reduced drive, loss of interest, and thoughts of self-harm or suicide². Cognitive symptoms and sleep disturbance (SD) are two non-mood-related symptoms of MDD^3,4. Previous studies have shown that the prevalence of SD is 60-90% in patients with MDD, while the prevalence of sleep disorders among these patients in the Chinese population is 85.22%⁵.

Protocol

The study was approved by the Academic Ethics Committee of the Inner Mongolia Mental Health Center (The Third Hospital of Inner Mongolia Autonomous Region, Brain Hospital of Inner Mongolia Autonomous Region) in Hohhot, China. An informed consent form was signed by all study participants.

1. PSG procedure

1. Data collection
   1. Include patients with MDD who were diagnosed according to the DSM-V.
      NOTE: This study included 22 patients with MDD who were di.......

Discussion

This two-part protocol has critical steps that demand attention. For PSG, scoring is the most important step; thus, PSG technicians need to be certified and experienced. In addition, before PSG, communication between technicians and participants is necessary because patients might feel uncomfortable and quit during PSG. For the cognitive screening tool, the critical step is evaluating the cognitive function with digitized equipment. Doctors need to introduce the procedures step by step to ensure the participant understan.......

Materials

Name	Company	Catalog Number	Comments
Computer	Surface	Surface pro2
Derivation	Compumedics	Grael
Electrode	Compumedics	Grael
Polysomnography	Compumedics	Grael
Software	Compumedics	Compumedics Profusion PSG4