ABSTRACT
Objective:
Restless Legs syndrome (RLS) is a common sleep disorder in clinical practice. In the prevalence studies conducted in different populations for RLS, different results ranging from 5% to 15% were obtained. This ratio ranges from 3.19% to 22.2% in Turkey. RLS, known to have adverse effects on sleep quality, can also affect mood, attention and cognitive functions. In our study, we aimed to investigate the possible effect of RLS on cognitive functions.
Materials and Methods:
In this study, patients diagnosed with RLS in the neurology outpatient clinic of our hospital were evaluated. Patients with possible mild cognitive impairment were excluded from the study by using the Standardized Mini Mental Test. After exclusion of secondary causes for RLS, 45 patients with idiopathic RLS and 20 healthy individuals were included in the study. Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), International RLS Severity Scale, Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Montreal Cognitive Assessment (MoCA) Scale were administered to all subjects.
Results:
In the RLS group; there was a statistically significant decrease in the MoCA components which demonstrate particularly orientation, abstract thinking and memory functions and in the MoCA total scores, compared to the control group (p=0.032, p=0.012, p=0.024, p=0.019, respectively). At the same time, there was a significant difference in the PSQI, ESS, ISI, BDI, and BAI values in the RLS cases.
Conclusion:
This study shows that the idiopathic RLS which correlated with disease duration may lead to insufficiency over functions in cognitive domains especially orientation, abstract thinking, and memory.
Keywords: Restless Legs syndrome, cognitive functions, orientation, abstract thinking, memory
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