Periodic Limb Movements during Sleep: A New Sleep-Related Cardiovascular Risk Factor?

Abstract

In recent years, a growing body of evidence suggests that periodic limb movements during sleep (PLMS) are associated with hypertension, cardiovascular, and cerebrovascular risk. However, several non-mutually exclusive mechanisms may determine a higher cardiovascular risk in patients with PLMS and the link between the two remains controversial. Prospective data are scant and the temporal relationship between PLMS and acute vascular events is difficult to ascertain because although PLMS may lead to acute vascular events such as stroke, stroke may also give rise to PLMS. This article describes the clinical and polygraphic features of PLMS and examines the literature evidence linking PLMS with an increased risk for the development and progression of cardiovascular diseases, discussing the possible pathways of this association.

Keywords: cardiovascular risk; cerebrovascular risk; hypertension; periodic limb movements during sleep; restless legs syndrome; stroke.

Figure 1

Polysomnographic recording of periodic limb movements during stage 2 non-REM sleep. Electromyographic bursts on the right anterior tibialis muscle (R. Tib) recur periodically every 15–20 s (see the arrows). EKG, electrocardiogram; Tib, tibialis anterior; R, right; L, left.

Figure 2

Excerpt of a polysomnographic tracing at a low paper speed. Note the association of periodic limb movements with increases in heart rate (asterisks). EKG, electrocardiogram; Tib, tibialis anterior; R, right; L, left; HR, heart rate.