The relationship between sleep disorders, anxiety, depression, and cognitive function with restless legs syndrome (RLS) in the elderly

Abstract

Restless legs syndrome (RLS) has a significant effect on sleep and quality of life. Delays in diagnosis and treatment are frequent due to a lack of awareness. In this study, a clinical analysis was performed to examine the relationship between sleep, mood, and cognitive function in RLS. According to the Pittsburgh Sleep Quality Index score (PSQI), patients with RLS were divided into a sleep disorders group (SD, PSQI\u2009>\u20097) and non-sleep disorders group (NSD, PSQI\u2009≤\u20097). Healthy controls were selected as a control group matched for age, cultural background, and marital status. We compared differences between the three groups using the Hamilton Anxiety Scale (HAMA), Hamilton Depression (HAMD), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA). The SD and NSD groups were also assessed with the Restless Leg Syndrome Rating Scale (RLSRS) and the severity of RLS between the two groups was compared. The analysis used t-test, ANOVA, and Pearson correlation. (1) Among the 54 RLS patients, 30 people in the control group, 35 patients with sleep disorders (SD, 65%), and 19 patients without sleep disorders (NSD, 35%), there were no significant differences in age, educational level, marital status, or trauma history. (2) The comparison results of the case group (SD and NSD) and the control group showed highly significant differences (P\u2009<\u20090.01) in the PSQI–HAMA–HAMD score but no significant differences between the NSD group, the SD group, and the control group in MMSE score. There was no difference between the NSD group and the control group in the MoCA, but a significant difference (P\u2009<\u20090.05) between the SD group and the control group was found. (3) The comparison between the NSD and the SD groups revealed significant differences in the RLSRS, HAMA, and HAMD scores (P\u2009<\u20090.05), but there were no statistical differences (P\u2009>\u20090.05) between two groups on MMSE and MoCA score. (4) Correlation and regression showed that there was a linear correlation between PSQI scores and RLSRS and HAMD scores in patients with RLS (P\u2009<\u20090.05). The regression equation was PSQI\u2009=\u2009\u2009−\u20092.393\u2009+\u20090.494 RLSRS\u2009+\u20090.170 HAMD. RLS patients were prone to sleep disorders, anxiety, and depression. Sleep disorders increased with the severity of the RLS and had some influence on the patient’s cognitive function. Sleep disorders were closely related to RLSRS and HAMD.