Sleep Disturbance Severity is Associated With Cognitive Impairment in Patients With First-episode, Treatment-naïve Major Depressive Disorders

Abstract

BackgroundSleep disorders and cognitive impairment are common in patients with major depressive disorder (MDD), though the relationship between the two remains unclear. We investigated this association in first-episode, treatment-naïve patients with MDD.MethodWe analyzed data from 242 patients withMDD. We divided the patients into 2 groups based on sleep disturbance severity and compared the cognitive impairment odds ratios in different domains between the groups.ResultsA total of 121 pairs of patients were matched (age39.4±10.1, 70.2% female). After propensity score matching, the odds ratios for cognitive impairment in patients with MDD and serious sleep disorders were 1.922 (1.068–3.459, P= 0.029) in executive functioning; 2.023 (1.211–3.379, P= 0.007) in executive shifting; 1.749 (1.000–3.060, P = 0.050) in executive inhibition; and 1.813 (1.038–3.167, P = 0.037) in information processing speed.LimitationsThe cross-sectional data on the relationship between sleep disorders and cognitive impairment were weak. Our study population was restricted to Chinese adults aged 18 to 65 years, so the results may not be generalizable to other populations.Because our sample size was limited, some variables were not included in the study.ConclusionsSleep disturbance is associated with cognitive impairment in the domains of executive functioning and information processing speed in first-episode, treatment-naïve patients with MDD. Sleep problems can be important symptoms for physicians in clinical practice and can aid in recognizing cognitive impairment in patients with MDD. Further study is required to confirm our results.Trial registrationClinicalTrials.gov: NCT02023567; registration date: December 2013.