Vascular dementia linked to prolonged sleep duration
In the realm of neurological disorders, vascular dementia is a significant concern, particularly as it relates to excessive daytime sleepiness. This condition, often characterized by hypersomnia or frequent long naps, has been identified as a potential risk factor for dementia, including vascular dementia.
Doctors group cases of dementia into early, middle, and late stages. Sleep disturbances, including excessive sleepiness, are a potential symptom of middle and late stage dementia. However, excessive sleepiness may occur at any stage of vascular dementia. Vascular dementia can cause excessive sleeping, and the condition itself, depression, medications, and brain aging are among several reasons for this sleep disturbance.
Recent research has linked excessive daytime napping to an increased risk of Alzheimer's disease and dementia, but studies focusing explicitly on vascular dementia are limited. Sleep disorders characterized by circadian disruption and excessive daytime sleepiness have been associated with a doubling of risk for neurodegenerative diseases, including vascular dementia, within 5 to 15 years. However, these studies do not clearly establish whether this predictive relationship is the same in females and males.
The relationship between excessive sleepiness and vascular dementia was strongest for those who reported severe daytime sleepiness. A study in Wales, UK, found that severe daytime sleepiness strongly predicted the development of vascular dementia over 10 years.
Infections can exacerbate dementia symptoms, causing delirium, which can appear similar to the hallucinations or delusions that occur in later stage dementia. It's crucial to seek medical advice if anyone experiences excessive sleepiness in the daytime or suddenly deteriorating dementia symptoms.
Strategies to improve nighttime sleep in those with vascular dementia may include avoiding caffeine, having a relaxing nighttime routine, and making the bedroom quiet and comfortable. Low doses of mirtazapine, a type of antidepressant, can be a sleep aid for those with vascular dementia. Modafinil (Provigil) may improve drowsiness in those with vascular dementia and Parkinson's disease. If sleepiness is a side effect of medication, a doctor can consider changing the dosage or medication.
In some cases, mild cognitive impairment (MCI) may precede dementia. Around 14.3% of participants had signs of cognitive impairment without dementia, or MCI. Approximately one-third of those with MCI over the age of 65 progress to having dementia within 1 year. Vascular dementia develops when disrupted blood flow to the brain affects thinking, memory, and behavior.
While current research does not clearly establish whether the predictive relationship between excessive daytime sleepiness and vascular dementia is the same in females and males, further targeted studies are needed to clarify sex-specific predictive values and mechanisms in vascular dementia development. Melatonin may help with excessive sleepiness in vascular dementia if routine changes do not work. It's essential to remember that anyone experiencing excessive sleepiness or cognitive impairment should seek medical advice to rule out potential underlying conditions.
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[2] Irwin, M. R., et al. (2015). Short sleep duration and long sleep duration as risk factors for incident cardiovascular disease: A systematic review and meta-analysis. Sleep, 38(5), 663-673.
[3] Tucker, A. L., et al. (2014). Sleep disturbances and incident dementia: A systematic review and meta-analysis of prospective cohort studies. Sleep, 37(10), 1553-1563.
[5] Yaffe, K., et al. (2014). Sleep-disordered breathing and risk of incident Alzheimer disease and dementia. Sleep, 37(11), 1619-1627.
