having frequent bad dreams and nightmares

An Early Warning Sign of Dementia Risk May Be Keeping You Up at Night,
Says Study
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More specifically, it showed that having frequent bad dreams and
nightmares (bad dreams that make you wake up) during middle or older
age, may be linked with an increased risk of developing dementia.

In the study, I analyzed data from three large US studies of health
and aging. These included over 600 people aged between 35 and 64, and
2,600 people aged 79 and older.

All the participants were dementia-free at the start of the study and
were followed for an average of nine years for the middle-aged group
and five years for the older participants.
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I found that middle-aged participants who experienced nightmares every
week, were four times more likely to experience cognitive decline (a
precursor to dementia) over the following decade, while the older
participants were twice as likely to be diagnosed with dementia.

Interestingly, the connection between nightmares and future dementia
was much stronger for men than for women.

https://www.sciencealert.com/an-early-warning-sign-of-dementia-risk-may-be-keeping-you-up-at-night-says-study

Lipophilic beta-blockers and those with higher serotonin 5HT1A
receptor affinity, shorter half-lives, and lack of alpha-blockade are
more likely to cause nightmares; thus, nightmares are more common with
propranolol, metoprolol, and pindolol [29] and least common with
sotalol, carvedilol, and labetalol [29]

https://www.uptodate.com/contents/nightmares-and-nightmare-disorder-in-adults/print