Correspondence

Restless Legs Syndrome and Spinal Anesthesia

N Engl J Med 2008; 359:2294-2296November 20, 2008

Article

To the Editor:

The restless legs syndrome (RLS) is a common sensorimotor disorder of unknown cause affecting approximately 10% of the population.1 One uncontrolled study showed that spinal anesthesia caused postoperative RLS.2 We conducted a prospective study to determine whether the occurrence of postoperative RLS was associated with the type of anesthesia.

Patients scheduled for surgery and general or spinal anesthesia were recruited from our hospital's lists of patients undergoing elective surgery (Table 1Table 1Characteristics of the Study Patients.). Using a standardized questionnaire (see the Supplementary Appendix, available with the full text of this letter at www.nejm.org), one of us interviewed patients — on admission and at 1 and 4 weeks postoperatively — about symptoms, including diagnostic criteria for RLS3 and symptoms of depression and daytime sleepiness. The questions regarding RLS symptoms were interspersed among other questions to mask the true objective of the survey, in order to avoid the response bias that often occurs with repeated questioning.

Thirty-two patients (8.9%) had preexisting RLS. No patients had new RLS postoperatively or worsening of preexisting symptoms. The 99% confidence interval for the risk of postoperative onset or worsening of RLS was 0 to 1.3% for the total sample and 0 to 1.6% for new-onset RLS. The 99% confidence interval for new-onset RLS was 0 to 4.0% for patients who had spinal anesthesia and 0 to 2.7% for patients who had general anesthesia (P=0.94).

The prevalence of RLS and the sex and age distributions of patients with RLS in our sample were consistent with those in other published reports.4 Our data do not support the hypothesis that spinal anesthesia induces RLS. Our results are not consistent with a previous study by Högl et al., which showed that RLS developed in 8% of patients treated with spinal anesthesia.2 The discrepancy between those findings and ours may be explained by limitations of this earlier study,2 which did not include a preoperative interview to assess patients for preexisting RLS. Differences in the study populations also may have contributed to the discrepancy. For example, 36% of the patients in the study by Högl et al. had a cesarean section with spinal anesthesia, which is associated with a high rate of postoperative nausea and vomiting; at the time of the study, postoperative nausea and vomiting were often treated with drugs, such as metoclopramide and droperidol, that are known to cause akathisia, a disorder that can be confused with RLS.5 We conclude that neither spinal anesthesia nor general anesthesia with propofol and an opioid induces or exacerbates the symptoms of RLS.

Thomas A. Crozier, M.D., Ph.D.
Desiree Karimdadian, M.D.
Svenja Happe, M.D.
University of Göttingen Medical School, 37075 Göttingen, Germany
tcrozie@gwdg.de

Dr. Crozier reports receiving lecture fees from Bristol-Myers Squibb; and Dr. Happe, lecture fees from Boehringer Ingelheim, GlaxoSmithKline, UCB, Roche, Pfizer, Cephalon, and Sanofi-Aventis. No other potential conflict of interest relevant to this letter was reported.

5 References

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   Hogl B, Frauscher B, Seppi K, Ulmer H, Poewe W. Transient restless legs syndrome after spinal anesthesia: a prospective study. Neurology 2002;59:1705-1707
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   Allen RP, Picchietti D, Hening WA, Trenkwalder C, Walters AS, Montplaisi J. Restless legs syndrome: diagnostic criteria, special considerations, and epidemiology: a report from the restless legs syndrome diagnosis and epidemiology workshop at the National Institutes of Health. Sleep Med 2003;4:101-119
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   Garcia-Borreguero D, Egatz R, Winkelmann J, Berger K. Epidemiology of restless legs syndrome: the current status. Sleep Med Rev 2006;10:153-167
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   Walters AS, Hening W, Rubinstein M, Chokroverty S. A clinical and polysomnographic comparison of neuroleptic-induced akathisia and the idiopathic restless legs syndrome. Sleep 1991;14:339-345
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Citing Articles (3)

Citing Articles

1. 1

   Mathieu Raux, Isabelle Arnulf. (2011) L’anesthésiste face au syndrome des jambes sans repos. Le Praticien en Anesthésie Réanimation 15:4, 239-242
   CrossRef

2. 2

   Mathieu Raux, Elias G. Karroum, Isabelle Arnulf. (2010) Case Scenario: Anesthetic Implications of Restless Legs Syndrome. Anesthesiology 112:6, 1511-1517
   CrossRef

3. 3

   (2009) More on the Restless Legs Syndrome and Spinal Anesthesia. New England Journal of Medicine 360:11, 1155-1156
   Full Text

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