Original Research

Restless Legs Syndrome Among Veterans With Spinal Cord Lesions

Fed Pract. 2018 April;35(suppl 3):S17-S20

References

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Discussion

This study represents one of the first studies to determine the prevalence of RLS in veterans with spinal cord disease. Research in this area is important to raise awareness of RLS among the veteran population with and without SCI and disorders. Restless legs syndrome often escapes diagnosis because of difficulty understanding the patient’s descriptions of their sensations. In addition, RLS may cause debilitating symptoms of sleep deprivation, daytime sleepiness, discomfort, and fatigue, which often results in decreased quality of life (QOL). Proper screening and treatment may improve QOL.

A study by Kumru and colleagues showed a similar rate of RLS in patients with SCI and RLS symptoms presented in the first year after SCI as did this study (18% vs 19%, respectively).⁴ In that study, RLS was more common in patients with lesions in lumbosacral area. Kumru and colleagues also showed that a dopaminergic medication improved symptoms of RLS in this population, whereas this study did not explore treatment outcomes.⁴

The pathogenesis of RLS is not fully known, but hereditary factors, iron metabolism, and the brain dopaminergic system are thought to be involved.¹¹ It is hypothesized that spinal cord lesions allow the appearance of RLS symptoms and spinal leg movement generator by blocking descending inhibitory spinal pathways.¹² One hypothesis is that damage to A11 nuclei (the main source of dopamine in the spinal cord or its diencephalospinal tract in animals) causes hyperexcitability of the spinal cord and leads to PLM and RLS symptoms.¹³ As the axons of A11 nuclei are present along the whole span of the spinal cord, SCI/D in patients with RLS might interrupt this dopaminergic tract and produce the RLS symptoms.

Limitations

This study included only veterans, so the prevalence may not apply to the nonveteran SCI population. Also, the population mainly was male, and there was no accurate information on race. Ferritin levels of the patients were not checked and is a major factor in RLS. The reported onset of RLS after the SCI could be due to recall bias.

Conclusion

The prevalence of RLS in veterans with SCI is above that reported in the general population (19% vs 10%, respectively). Furthermore, those with RLS have symptoms that often started after the SCI (suggesting causality) and required therapy due to their level of RLS symptom burden. A spectrum of severity of symptoms is present among those with RLS, with 83% having moderate-to-severe RLS affecting their QOL.

Although there was not a statistically significant relationship between RLS and spinal cord lesion level, there was a slightly higher prevalence of RLS at the cervical and thoracic levels, which may be relevant for future studies. There was no difference found between the RLS subgroups with respect to the location of the lesion within the spinal cord; however, a larger sample size may be needed to determine whether this would reach statistical significance. Prompt search for symptoms of RLS in veterans with SCI is warranted to provide adequate treatment to improve sleep health and QOL in this population.

Restless Legs Syndrome Among Veterans With Spinal Cord Lesions

References

Discussion

Limitations

Conclusion

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