Pase et al. stated changes in REM sleep may not be a marker of prodromal dementia, but that it may actually be protective against cognitive decline, and further studies were needed. [1] The authors used a model to account for confounding factors including antidepressant use, which is known to suppress REM sleep in healthy and depressed patients. [2] If REM sleep is protective for dementia, it would be interesting to perform a longitudinal prospective cohort study with polysomnogram data to analyse if exposure to medications that reduce REM sleep has an increased incidence of dementia. This may be confounded by psychiatric factors, such as heightened anxiety being implicated as a possible risk factor for dementia. [3] However, medications, such as duloxetine, are often used for non-psychiatric indications (eg, neurogenic pain).
The authors mentioned a lack of information on shift work and an inability to ascertain if sleep occurred outside of a physiologic-preferred period. [1] With this information, sleep deprivation and possible subsequent REM rebound could be catalogued. Furthermore, inclusion of other confounding factors that affect REM sleep, such as alcohol use, may have been beneficial.
1. Pase M, Himali JJ, Grima NA, et al. Sleep architecture and the risk of incident dementia in the community. Neurology Epub 2017 Aug 23.
2. Kluge M, Schussler P, Steiger A. Duloxetine increases stage 3 sleep and suppresses rapid eye movement (REM) sleep in patients with major depression. Eur Neuropsychopharmacol 2007;17:527-531.
3. Gulpers B, Ramakers I, Hamel R, et al. Anxiety as a Predictor for Cognitive Decline and Dementia: A Systematic Review and Meta-Analysis. Am J Geriatr Psychiatry 2016;24:823-842.
For disclosures, please contact the editorial office at [email protected].
Pase et al. stated changes in REM sleep may not be a marker of prodromal dementia, but that it may actually be protective against cognitive decline, and further studies were needed. [1] The authors used a model to account for confounding factors including antidepressant use, which is known to suppress REM sleep in healthy and depressed patients. [2] If REM sleep is protective for dementia, it would be interesting to perform a longitudinal prospective cohort study with polysomnogram data to analyse if exposure to medications that reduce REM sleep has an increased incidence of dementia. This may be confounded by psychiatric factors, such as heightened anxiety being implicated as a possible risk factor for dementia. [3] However, medications, such as duloxetine, are often used for non-psychiatric indications (eg, neurogenic pain).
The authors mentioned a lack of information on shift work and an inability to ascertain if sleep occurred outside of a physiologic-preferred period. [1] With this information, sleep deprivation and possible subsequent REM rebound could be catalogued. Furthermore, inclusion of other confounding factors that affect REM sleep, such as alcohol use, may have been beneficial.
1. Pase M, Himali JJ, Grima NA, et al. Sleep architecture and the risk of incident dementia in the community. Neurology Epub 2017 Aug 23.
2. Kluge M, Schussler P, Steiger A. Duloxetine increases stage 3 sleep and suppresses rapid eye movement (REM) sleep in patients with major depression. Eur Neuropsychopharmacol 2007;17:527-531.
3. Gulpers B, Ramakers I, Hamel R, et al. Anxiety as a Predictor for Cognitive Decline and Dementia: A Systematic Review and Meta-Analysis. Am J Geriatr Psychiatry 2016;24:823-842.
For disclosures, please contact the editorial office at [email protected].