Elsevier

Sleep Medicine

Volume 16, Issue 1, January 2015, Pages 186-189
Sleep Medicine

Brief Communication
Diagnostic value of the REM sleep behavior disorder screening questionnaire in Parkinson's disease

https://doi.org/10.1016/j.sleep.2014.08.014Get rights and content

Highlights

  • Validation of the RBD screening questionnaire (RBDSQ) in 2 patient samples with Parkinson's disease.

  • The diagnostic value of the RBDSQ differed substantially between both samples.

  • The main difference was the individual's awareness on RBD.

  • This critical finding deserves clarification before use in epidemiological studies is recommended.

Abstract

Objective

We aimed to validate the rapid eye movement (REM) sleep behavior disorder (RBD) screening questionnaire (RBDSQ) in 2 independent samples of patients with Parkinson's disease (PD) using different settings when performing the investigations.

Methods

The RBDSQ was administered to two independent samples of 52 and 75 consecutive PD patients investigated with video-polysomnography (vPSG).

Results

In sample A, the RBDSQ identified 46/52 (88.5%) patients correctly. In sample B, 50/75 (66.7%) patients were identified correctly. Considering a cut-off score of ≥ 5 as a positive test result, sample A showed a sensitivity of 0.90 and a specificity of 0.87, sample B showed a sensitivity of 0.68 and a specificity of 0.63. Main differences between both groups were that patients of sample A underwent a sleep history including RBD assessment prior to administration of the RBDSQ, whereas in sample B the RBDSQ was administered during routine work-up.

Conclusions

The diagnostic value of the RBDSQ strongly depends on the clinical setting and may be influenced by the individual's awareness on RBD. This finding is a critical issue which deserves clarification before use of this and other questionnaires can be recommended in epidemiological studies.

Introduction

Rapid eye movement (REM) sleep behavior disorder (RBD) is clinically characterized by the intermittent loss of physiological skeletal muscle atonia during REM sleep with the appearance of elaborate motor activity associated with dream mentation [1]. Apart from the characteristic clinical picture, polysomnography (PSG) demonstrating REM sleep without atonia is required for establishing a definite diagnosis of RBD [2]. The RBD screening questionnaire (RBDSQ) was developed and validated to meet the need for an easily applicable and short diagnostic screening tool [3]. It was shown to have a high sensitivity for RBD in both sleep-disorder patients and healthy controls [3]. Up to 46% of Parkinson's disease (PD) patients have RBD [4], [5], [6]. Since the usefulness of the RBDSQ in PD is still controversial [7], [8], [9], we aimed to validate the RBDSQ in 2 independent samples of PD patients using different settings when performing the investigations.

Section snippets

Patient samples and procedures

All patients in this study were referred to video-PSG (vPSG) at the sleep laboratory of Innsbruck University or at the Paracelsus-Elena-Klinik Kassel because of reported sleep disturbances, and underwent single or multiple night v-PSG according to clinical considerations. The RBDSQ [3] was completed prior to vPSG.

All patients analyzed in this study consented to scientific evaluation of their clinical data. The Ethical Committee of the Landesärztekammer Hessen agreed to the project.

Patient

Clinical characteristics (Table 1)

Discussion

This study evaluated the diagnostic value of the RBDSQ in two samples of PD patients, and found substantial and surprising differences of sensitivity and specificity between both samples: whereas sensitivity and specificity were high in sample A, they were at best moderate in sample B.

Which factors might potentially account for this discrepancy? First, sample A consisted of PD patients who had a sleep interview including RBD assessment prior to the RBDSQ, which alerted the patients about RBD as

Conflict of interest

The ICMJE Uniform Disclosure Form for Potential Conflicts of Interest associated with this article can be viewed by clicking on the following link: http://dx.doi.org/10.1016/j.sleep.2014.08.014.

. ICMJE Form for Disclosure of Potential Conflicts of Interest form.

Acknowledgment

We are grateful to Laura Ehrmann, MD, and Tina Falkenstetter, MD PhD, for attentive and dedicated assistance with the Innsbruck patients' questionnaires.

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  • Cited by (0)

    1

    Both authors contributed equally to this paper.

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