Serum Trace Elements Concentrations in Patients with Restless Legs Syndrome

Area of Science:

• Neuroscience
• Biochemistry
• Clinical Medicine

Background:

• Idiopathic restless legs syndrome (iRLS) has been linked to altered zinc levels, suggesting a role in its pathogenesis.
• Previous studies indicated normal levels of other trace elements like magnesium, calcium, manganese, iron, and copper in iRLS patients compared to controls.

Purpose of the Study:

• To investigate serum concentrations of trace elements associated with oxidative stress or peripheral nerve toxicity in a large cohort of iRLS patients.
• To clarify the role of specific trace elements in the pathophysiology of iRLS.

Main Methods:

• Serum levels of 12 trace elements (iron, copper, manganese, zinc, magnesium, selenium, calcium, aluminium, lead, cadmium, arsenic, mercury) were measured.
• Inductively Coupled Plasma Mass Spectrometry was used for analysis in 100 iRLS patients and 110 age- and sex-matched controls.
• Statistical analysis was performed to compare trace element levels between groups and assess correlations with clinical parameters.

Main Results:

• Serum concentrations of copper, magnesium, selenium, and calcium were significantly elevated in iRLS patients compared to controls.
• No significant correlations were found between serum trace metal levels and age at onset, RLS severity, family history, or drug response.
• The study did not replicate previous findings of increased serum zinc in iRLS patients, suggesting potential analytical method variability in prior research.

Conclusions:

• This study identifies an association between elevated serum copper, magnesium, selenium, and calcium levels and restless legs syndrome in a Spanish Caucasian population.
• The findings suggest a specific trace element dysregulation, distinct from zinc, may be implicated in iRLS.
• Discrepancies with prior zinc findings highlight the importance of analytical method accuracy in trace element research for iRLS.