How often have you woken up after a bad dream? Nightmares can be common in young children, which explains why children want to either sleep with a nightlight or crawl into their parents’ bed. Having a nightmare or a distressing dream can also be common for adults, affecting up to 29% of people every month, per a 2009 article in Sleep Medicine Clinic.
For some people, distressing dreams are a weekly occurrence. Stressful life circumstances, certain medications, or doomscrolling before bedtime can factor into the frequency of your frightening dreams. According to a 2022 article in eClinicalMedicine (a Lancet journal), your frequent nightmares also might indicate stress on your brain (and here’s what nightmares do to your body).
The study asked two groups –- one group of middle-aged adults (average age of 50) and another group of older adults (average age of 83) — about how often they experienced distressing dreams. Several years later, the researchers followed up with cognitive tests (in middle-aged adults) or dementia diagnosis (in older adults). The middle-aged adults who experienced more frequent distressing dreams were four times more likely to experience cognitive decline years later. The older adults with more occurrences of distressing dreams were twice as likely to be diagnosed with dementia.
Why bad dreams might be linked with dementia
A 2023 article in Scientific American said that you often rehearse or relive what’s going on in your life. There’s an important three-way dialogue occurring between areas of your brain during REM sleep –- the stage of sleep where most dreams occur. This dialogue helps to process what’s going on in your life with reduced emotional intensity.
One part of your brain is responsible for downregulating negative emotions in your dreams and waking life. If this part of your brain isn’t functioning well, these negative emotions can interrupt your sleep. The study also found that the older adults who were diagnosed with depression were 89% more likely to be diagnosed with dementia.
The researchers suggested that doctors could monitor the frequency of distressing dreams throughout an adult’s life well before any cognitive decline or dementia diagnosis occurs. Prazosin, a medication that treats nightmares, has also been found to prevent memory decline and the amyloid plaques linked to Alzheimer’s disease. (Read about other health risks caused by nightmares.)
Why people experience nightmares
Just because you have a nightmare doesn’t necessarily mean you’re at risk for dementia. There are other reasons for your bad dreams that can be linked to your lifestyle. Eating something before bed could get your metabolism going, boosting your brain activity while you’re sleeping. Sleep deprivation could also be the cause of your distressing dreams. Most nightmares occur during your REM sleep, and these REM intervals get longer as you continue to sleep. However, alcohol, caffeine, or drugs can interrupt your sleep cycle. For example, drinking alcohol at night might help you fall asleep more quickly, but then your body rebounds hours later, causing your REM cycle to go on high alert.
You should talk to your doctor if you frequently experience distressing dreams to see if it’s a psychological or physiological condition. Some medications, such as antidepressants, antipsychotics, beta-blockers, melatonin, or semaglutide injections, could aggravate nightmares, so your doctor could adjust your dosage to see if your nightmares become less frequent. Practicing good sleep hygiene while also finding ways to manage your life stressors can help you sleep better and reduce the occurrences of distressing dreams.