Letter to the Editor

The article “Understanding RBD” by Margelli and Loube in the January/February issue of Sleep Review contains a number of egregious errors such as “Sleep fragmentation from sleep apnea or periodic limb movements may trigger RBD because of the increased arousability accompanying these disorders.”

Such grossly erroneous information is of great disservice to your readership and sponsors. We suggest you change the review process.

Mark W. Mahowald, MD
Carlos Schenck, MD
Andrea Patterson, RPSGT
MN Regional Sleep Disorders Center
Hennepin County Medical Center
Minneapolis, Minn

Authors’ reply
We greatly appreciate the letter from Dr Mahowald and his colleagues from Minnesota. They have a well-deserved reputation in the area of REM behavior disorder (RBD), and we thank them for their interest in this matter.

We do, however, maintain our belief that patients with both RBD and sleep apnea are likely to benefit from the treatment of sleep apnea in decreasing the propensity for the disorder.

RBD and sleep apnea have a predilection for occurring in elderly men. Thus, it is not uncommon for patients to present to our clinic with symptoms and diagnostic findings of both disorders. As well, many of these patients have worsening of sleep apnea in REM stage sleep due to the autonomic instability of this sleep state. We have found that when these patients are successfully treated with CPAP, the degree of sleep fragmentation occurring in all sleep stages, including REM sleep, is decreased, and there are fewer REM-related behaviors.

As Dr Mahowald and his associates state, there is no connection between the treatment of periodic limb movements of sleep (PLMS) and RBD. Indeed, PLMS rarely occurs in REM sleep, as voluntary muscle atonia characterizes that sleep state. We apologize for this error.

Daniel I. Loube, MD
David M. Margelli, PA-C
Swedish Sleep Medicine Institute