Periodic leg movements and restless legs syndrome

Study objectives

Periodic leg movements (PLM) are a common phenomenon in several somatic and psychiatric disorders, often related to sleep disorders. We examined the prevalence of PLM, periodic leg movement disorder (PLMD), and restless legs syndrome (RLS) in psychiatric inpatients suffering from severe sleep disturbances and tried to find possible influences of the prescribed medication.

Design, setting and patients

In a retrospective data analysis, we explored the patient’s records in 117 psychiatric inpatients, suffering from comorbidity with severe sleep disturbances.

Measurements and results

We found PLM was positive in 61.5% of our sample, while diagnosing PLMD in 25.6% and RLS in 19.7%. A total of 74% of our RLS patients suffered from PLM. Adding dopaminergic medication or reducing neuroleptic agents improved subjective sleep quality and lowered PLM indices in patients with persistent sleep disturbances. Age-related results showed high PLM scores in patients below 40 years.

Conclusions

PLM occurred in more than 60% of the study group and a PLMD was found in about 25% of our patients. We found PLM indices in our younger patients relatively high in comparison with healthy adults. However, we found no statistically significant influence of the initially prescribed medication – maybe due to polypharmacy. Goal-directed addition of dopaminergic agents or the reduction of neuroleptic drugs results in lower PLM indices and improved subjective sleep quality.