Is there a higher risk of restless legs syndrome in peripheral neuropathy?

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Neurology. 2009 Mar 17;72(11):955-60.

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Neurology. 2009 Mar 17;72(11):950-1.

Is there a higher risk of restless legs syndrome in peripheral neuropathy?

Hattan E, Chalk C, Postuma RB.

Department of Neurology & Neurosurgery, McGill University, Montreal General

Hospital, Montreal, Quebec, Canada.

OBJECTIVE: Associations between peripheral neuropathy and restless legs syndrome

(RLS) have been described, but have not been consistently reproduced. If RLS

prevalence is truly increased by neuropathy, this has important implications for

RLS pathophysiology.

METHODS: In a case-control design, 245 patients with peripheral neuropathy and

245 age- and sex-matched controls were screened for RLS using a standardized

phone questionnaire based on international RLS diagnostic criteria. All persons

who answered yes to three of four criteria were considered screen-positive. All

screen-positive patients underwent a confirmatory diagnostic evaluation by a

movement disorders specialist blinded to the neuropathy status of the patient.

RLS prevalence was calculated and compared using Fisher exact test.

RESULTS: A total of 65 (26.5%) patients with neuropathy screened positive

compared to 25 (10.2%) controls (p < 0.0001). However, the diagnosis was

confirmed in only 46% of screen-positive patients with neuropathy, vs 80% of

controls (p = 0.005). Cramps and paresthesia without true diurnal variation or

rest exacerbation were the commonest causes of false-positive screens. After

diagnostic confirmation, the overall prevalence of RLS did not differ between

neuropathy patients and controls (12.2% vs 8.2%, p = 0.14). However, when

classified by etiology, RLS was found in 14/72 (19.4%) patients with hereditary

neuropathy, a prevalence higher than found in controls (p = 0.016) and acquired

neuropathy (9.2%, p = 0.033). Among patients with neuropathy, those with RLS

more commonly had a family history of RLS (37% vs 15%, p = 0.007) and were

younger (49.9 vs 61.4, p = 0.0003).

CONCLUSIONS: Restless legs syndrome is more prevalent among patients with

hereditary neuropathy, but not in those with acquired neuropathies.