ated with MEIS1  and BTBD9  are less common in individuals of African or Asian descent,
perhaps suggesting lower risk fo r RLS in these populations. 
Pathophysiological mechanisms in RLS also in clude disturbances in the central dopa-
minergic system and disturbances in iron  metabolism. The endo genous opiate system
may also be involved. Treatment effect s of dopaminergic drugs (primarily D2 and D3 non-
ergot agonists) provide further support that  RLS is grounded in dysfunctional central
dopaminergic pathways. While the effective treatment of RLS has also been shown to sig-
nificantly reduce depressive symptoms, seroto nergic antidepressants can induce or aggra-
vate RLS in some individuals. 
Gender-Related Diagnostic Issues
Although RLS is more prevalent in females than  in males, there are no diagnostic differ-
ences according to gender. However, the prev alence of RLS during pregnancy is two to
three times greater than in the general population. RLS associated with pregnancy peaks
during the third trimester and improves or reso lves in most cases soon after delivery. The
gender difference in prevalence of RLS is explai ned at least in part by parity, with nullipa-
rous females being at the same r isk of RLS as age-matched males.
Diagnostic Markers
Polysomnography demonstrates  significant abnormalities in RLS, commonly increased
latency to sleep, and higher arousal index.  Polysomnography with a preceding immobili-
zation test may provide an indicator of the motor sign of RLS, periodic limb movements,
under standard conditions of sleep and during quiet resting, both of which can provoke RLS
symptoms.
Functional Consequences of Restless Legs Syndrome