There is a growing body of evidence regarding the clinical significance of PLMS, and this movement disorder is of concern in both clinical and scientific contexts. Leg actigraphy is a convenient and promising method for screening periodic limb movements in sleep (PLMSs). This study aims to demonstrate the reliability of the SOMNOwatch™ actigraph for detecting periodic limb movements in sleep. Twenty-eight patients, referred to a sleep laboratory for various sleep problems, underwent nocturnal polysomnography with simultaneous one-sided actigraphy using the SOMNOwatch™ actigraph. Recordings of leg movements obtained from both methods were manually scored, calculating the periodic limb movement index (PLMI). The agreement between the methods was assessed through correlation analysis and event-by-event comparison. The correlation between the PLMI derived from PSG and SOMNOwatch™ was high and statistically significant (r = 0.98, p < 0.0001). The SOMNOwatch™ demonstrated a sensitivity of 86.7% and a specificity of 92.3% in detecting PLMS. Similarly, for detecting patients with a PLMI equal to or greater than 15, the sensitivity was 85.7%, and the specificity was 95.2%.
Keywords: SOMNOwatch; actigraphy; periodic limb movements; polysomnography; validation.