Polysomnographic findings in restless legs syndrome (RLS) patients with severe augmentation

Augmentation can occur frequently in restless legs syndrome (RLS) patients treated with dopaminergic agents. Video-polysomnographic (PSG) data from augmented RLS patients are scant. The aim of this study was to evaluate PSG findings in augmented RLS patients and compare them with those of non-augmented RLS patients.

Valid PSG data were analyzed from 99 augmented and 84 non-augmented RLS inpatients who underwent one night PSG.

Both patient groups showed a high subjective burden of RLS symptoms. The mean scores on the International RLS Study Group Rating Scale (IRLS) were significantly higher in the group with augmentation than in the group without. The periodic leg movement index (PLMI) was increased in both groups, mostly on account of the PLM in wakefulness (PLMW). Both groups presented a reduced sleep efficiency and an increased sleep latency. The levodopa equivalent dose (LED) was significantly higher in the augmented group.

Our study confirms that RLS patients with augmentation have disturbed sleep due to high amount of leg movements and fragmented sleep. Overall, however, polysomnographic characteristics were not different between insufficiently treated RLS and severely augmented RLS patients, implying that augmentation could represent a severe form of RLS and not a different phenomenon.