Q. My husband often flails his arms and sometimes yells while he’s sleeping. Could he be acting out his dreams?
A. It’s possible that your husband has a syndrome known as rapid eye movement sleep behavior disorder, or RBD. Relatively rare and frequently undetected, RBD appears in 0.5 percent of the general population and 2 percent of older people, most often in men over age 50.
The condition involves regularly acting out dreams physically with actions that range from mild hand gestures to thrashing, hitting, and punching. Sufferers also may talk or yell out obscenities.
Because your husband has the potential to injure you or himself during an episode, he should be evaluated by a sleep specialist, who will likely order an overnight sleep study. If diagnosed with RBD, he may be counseled to try melatonin supplements to quiet the flailing and vocalizing, or he may be prescribed an anticonvulsant drug.
You may need to make changes in your sleeping environment, such as moving loose objects away from the bed or adding padded bed rails, to avoid any danger.
Experts have determined that RBD can be a precursor to the development of a neurodegenerative disorder such as Parkinson disease, Lewy body dementia, or multiple system atrophy, although the onset of such a disorder may be months or even decades after the initial occurrence of RBD.
If your husband is diagnosed with RBD, he should follow up with a neurologist or other practitioner familiar with Parkinson's disease so he can be evaluated for subtle signs of neurocognitive disease and possibly take advantage of emerging treatments.