Restless Leg Syndrome And ED

Men with restless leg syndrome (RLS) had a significantly increased risk of erectile dysfunction compared with men who did not have the neurologic disorder, data from a large cohort study showed.

The likelihood of erectile dysfunction increased with the frequency of restless leg episodes, reaching an adjusted risk apex about 80% greater for men with the most frequent episodes of RLS compared with men who did not have the syndrome, according a report in the January issue of Sleep.

The findings suggest a common etiology for restless leg syndrome and erectile dysfunction and support preclinical evidence of altered neurotransmitter receptors linking the two conditions.

"This finding indirectly supports a role of dopamine in restless leg syndrome," Xiang Gao, MD, PhD, of Brigham and Women's Hospital and Harvard, and colleagues wrote. "Further epidemiologic studies are warranted to clarify the temporal relationships between restless leg syndrome and erectile dysfunction and to explore the biological mechanisms underlying this association."

Although the etiology of RLS remains unclear, dopaminergic hypofunction in the central nervous system (CNS) has been implicated in the condition's pathophysiology. The dopamine hypothesis has been supported by studies showing that RLS symptoms improve with administration of L-dopa or a dopamine agonist and worsen with administration of dopamine antagonists that cross the blood-brain barrier, the authors wrote.

Dopamine may also play a role in erectile function. For example, Gao and colleagues previously reported an association between erectile dysfunction and Parkinson's disease, another condition involving dopamine hypofunction in the CNS (Am J Epidemiol 2007; 166: 1446-50).