Retinal nerve fiber layer thinning: a window into rapid eye movement sleep behavior disorders in Parkinson’s disease
- 301 Downloads
Retinal nerve fiber layer (RNFL) thinning occurs in Parkinson’s disease (PD) and other neurodegenerative diseases. Idiopathic RBD (iRBD) is a well-established prodromal hallmark of synucleinopathies and occurs secondary to many neurodegenerative diseases, including PD. The aim of this study is to determine whether or not retinal structures are altered with the onset of rapid eye movement (REM) sleep behavior disorders (RBD).
In all, a total of 63 patients with PD, 14 patients with idiopathic RBD, and 26 sex- and age-matched healthy controls were enrolled and underwent optical coherence tomography measurements (HD-OCT (Zeiss) ) for the average and every quadrant of RNFL thickness. The REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) was used to classify PD patients with clinically probable RBD (PD + pRBD) or without probable RBD (PD − pRBD). Patients with iRBD were identified by polysomnography.
For patients with RBD (idiopathic or secondary to PD), we found a significant decrease in RNFL thickness compared with groups without RBD (PD − pRBD and healthy controls) (all p < 0.05). Average RNFL thickness in patients with iRBD is significantly thinner than in healthy controls (p < 0.05). In PD, the average RNFL thickness was dramatically thinner in the PD + pRBD group than the PD − pRBD group (p < 0.005). Compared with healthy controls, RNFL thickness was slightly thinner in the drug-naive PD group but not the PD group with drug treatment. Multiple linear regression analysis showed that RBDSQ score was negatively associated with average and inferior RNFL variation in PD (all p < 0.005).
The findings show that RNFL was slightly but significantly thinner in idiopathic RBD. In PD, RNFL thickness may vary depending on the presence of RBD.
KeywordsIdiopathic rapid eye movement sleep behavior disorders Rapid eye movement sleep behavior disorders Parkinson’s disease Retinal nerve fiber layer thickness Optical coherence tomography measurement
- PD + pRBD
PD patients with clinical probable RBD
- PD − pRBD
PD patients without probable RBD
Retinal nerve fiber layer
newly diagnosed PD patients with drug-naive
PD patients exposure to drug treatment
Chun-feng Liu, Zi-jiao Yang, Cheng-jie Mao conceived and designed the experiments. Zi-jiao Yang, Jing Wei, and Xiao-yan Ji performed the experiments. All authors analyzed the data, discussed the results and co-wrote and commented on the manuscript. All authors have approved the final article.
Compliance with ethical standards
All funding sources and potential conflicts of interest from each author that relate to the research were covered in the article.
Funding sources for study
This work was supported by the Jiangsu Provincial Special Program of Medical Science (BL2014042); Suzhou Clinical Key Disease Diagnosis and Treatment Technology Foundation (LCZX201304); and Suzhou Clinical Research Center of Neurological Disease (Szzx201503). This was also partly supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
- 13.Kramer SG, Potts AM, Mangnall Y (1971) Dopamine: a retinal neurotransmitter. II. Autoradiographic localization of H3-dopamine in the retina. Investig Ophthalmol 10:617–624Google Scholar
- 22.American Academy of Sleep Medicine (2007) The AASM manual for the scoring of sleep and associated events—rules, terminology and technical specifications. American Academy of Sleep Medicine, Westchester, ILGoogle Scholar