Prognostic Counseling for Patients With Idiopathic/Isolated REM Sleep Behavior Disorder: Should We Tell Them What's Coming? Yes

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by often violent dream enactment behavior, such as sleep‐related vocalization, screaming or shouting, punching, arm flailing, or kicking movements, that parallel the content of a nightmare or vivid dream.1, 2 Diagnosis requires confirmation by polysomnography (PSG), which demonstrates its neurophysiological signature of REM sleep atonia loss (a.k.a., REM sleep without atonia).3, 4, 5 iRBD has been recently demonstrated to be a common neurological disorder in the general population with a prevalence of approximately 1% to 2%.6, 7 Whether RBD is idiopathic/isolated (iRBD) or symptomatic, RBD is strongly associated with synucleinopathy neurodegenerative disorders, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and MSA.1, 2, 8, 9, 10 Even iRBD is strongly associated with symptoms or signs of an underlying covert syncleinopathy, with up to 80% of iRBD patients having nonmotor manifestations of autonomic, cognitive, olfactory, or visual manifestations, or “soft” motor signs insufficient for PD diagnosis of bradykinesia, rigidity, tremor, or postural instability at the time of diagnosis by PSG.10, 11 Approximately 70% of iRBD patients develop PD, DLB, or MSA over longitudinal follow‐up of 10 to 15 years, and currently there is no proven beneficial neuroprotective strategy or therapy to prevent the evolution of increasingly devastating neurological deficits.10 Given this, there is currently prevailing uncertainty about the utility of prognostic counseling for iRBD patients, who are at high risk for future development of a neurodegenerative disorder. Should we tell them about their likely future, and if so, what should we tell them?12

Prognostic counseling in iRBD is further complicated by how the patient presents and is given the diagnosis. In between 50% to 60% of patients, dream enactment is not the patient's primary clinical complaint or concern in the sleep clinic, given that they may instead first present for concerns related to obstructive sleep apnea, restless legs syndrome, hypersomnia symptoms, or chronic insomnia.13 Previous research suggests that sleep clinic populations are unsurprisingly enriched for the discovery of iRBD, with approximately 5% of sleep clinic cohorts having an iRBD diagnosis.14 In another recent study, 11% of patients had another presenting primary sleep complaint and RBD diagnosis was elicited only upon specific questioning, whereas 44% of patients in this cohort were unaware of their dream enactment behaviors.13 These data are consistent with our clinical experience in sleep medicine clinics where RBD is commonly discovered in the history taking process, by screening questionnaires, or even as a secondary and incidental finding during PSG indicated for another primary sleep concern. As such, not all iRBD patients receiving a diagnosis are aware of their dream enactment; many do not consider it a significant concern in their daily lives and are less likely to be seeking prognostic information. For these patients, relaying bad news is much more difficult than if the patient had a primary focus on their dream enactment as a chief complaint. Despite this differential presentation, recent evidence suggests that iRBD as a primary/chief or secondary complaint follows a similarly poor prognostic trajectory toward acquiring overt neurodegenerative disease.13

Currently, there are limited data concerning prognostic counseling of RBD patients. In one recent study, only 47% of adults with iRBD received prognostic counseling (or, at least, documentation concerning counseling), and male neurologists were most likely to have documented counseling in the electronic medical record.15 A more recent study of worldwide experts found that most RBD subspecialty experts provided prognostic counseling, but few asked patients their views concerning their preferences. There are currently no published studies concerning iRBD patient preferences regarding prognostic counseling.

Given this evidence vacuum, providers must currently utilize their best judgment and individualize counseling for their specific patients. One prevailing view is that patients seem highly likely to learn about the strong associations between RBD and synucleinopathy risk regardless of what is discussed in the office, given wide availability of the Internet and increasing evidence that patients may seek medical information from this source. Given this, it may be logical to counsel proactively to avoid erosion of trust in the physician‐patient relationship.

The ethical principle of respect for autonomy holds that patients have a right for self‐determination, including knowing as much as possible about their future risk and likelihood for developing a disease, and withholding prognostic information that may be valued by the patient would therefore constitute a breach of the physician's fiduciary responsibility. Despite the current lack of actionability for an ultimately poor and undesirable neurodegenerative disease, additional advantages for transparency in providing counseling to iRBD patients include future life planning regarding finances, health, and retirement. Informed by a likely future with a high risk for developing a neurodegenerative disease, iRBD patients who are currently healthy may want to contemplate their values and preferences for future health needs (including advance care directive documentation), purchase additional insurance for long‐term care, ensure adequate financial resources available to support their future health needs, or even accelerate retirement planning (including pursuit of their individual “bucket list” wishes and plans).

On the other hand, the principle of nonmaleficence demands that physicians carefully consider and minimize any potential harms that may be incurred by prognostic counseling. Whereas there is no evidence that prognostic counseling may be harmful for most patients, caution is needed especially for some individuals with significant mental health comorbidities who may be more vulnerable to experience worsened anxiety or deterioration in mood state.

Asking about the iRBD patient's own values and preferences should be the first step in considering prognostic counseling. At a minimum, the iRBD patient should be informed that there is a strong association with other underlying or future neurological diseases, which then presents an opportunity to inquire whether they wish to know more about this association, and if so, when they would wish to be told, and in how much depth. Future research concerning iRBD patients’ values and preferences is greatly needed, to inform best practices concerning counseling, but at the current time, at least discussing and documenting the strong iRBD/neurodegenerative disease risk association is a good start.

Disclosures

Ethical Compliance Statement: IRB Review/Declaration of patient consent: not applicable (opinion piece, without protected health information data). The author confirms that he has read the Journal's position on issues involved in ethical publication and affirms that this work is consistent with those guidelines.

Funding Sources and Conflicts of Interest: This project was supported by Mayo Clinic Alzheimer's Disease Research Center Grant Award from the National Institute on Aging (P50 AG016574) and the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant Number 1 UL1 RR024150‐01. The content is solely the responsibility of the author and does not necessarily represent the official views of the NIH. The author reports no conflicts of interest.

Financial Disclosures for previous 12 months: Research support from NIH NHLBI, NIA, Sunovion, Inc., and Michael J. Fox Foundation (no personal fees).