Seasonal Changes and Dementia Symptoms
Many people with dementia notice their symptoms shift with the seasons. Winter often brings tougher days, while spring and summer might ease things a bit. These changes happen because less daylight messes with the body’s inner clock, called the circadian rhythm. This clock controls sleep, mood, and energy. In older adults, weak or uneven rhythms raise dementia risk and make symptoms worse during dark months.[3]
Think about winter first. Days get shorter, and sunlight drops. This can spark something called Seasonal Affective Disorder, or SAD. SAD acts like depression but ties directly to the season. Signs include feeling sad or hopeless all the time, extreme tiredness, trouble focusing, sleeping too much, craving sweets, gaining weight, and pulling away from friends.[1][2] For seniors, eyes that let in less light due to aging add to the problem. Bad weather keeps people indoors, boosting isolation, which feeds low moods.[1]
Now link this to dementia. People with dementia already struggle with confusion about time and place. They might forget dates or seasons more often.[4] In winter, early darkness stirs sundowning. This is when confusion, anxiety, or agitation ramps up in the late afternoon or evening. Shorter days disrupt sleep cycles, making sundowning hit harder.[6] Time changes in spring or fall confuse things too. Loved ones with Alzheimer’s may get more mixed up or have sleep issues right after clocks shift.[5]
Mood swings fit here as well. Dementia brings irritability, withdrawal, or odd judgments.[4] Winter blues pile on with fatigue, sleep changes, and less interest in hobbies.[7] Physical aches like joint pain or headaches might feel sharper too.[2] All this overlaps, so spotting seasonal patterns helps tell SAD from dementia flares.
Light plays a big role. Less sun cuts vitamin D, which supports brain health and fights fatigue.[1] Weak rhythms mean activity peaks later in the day, like after 2 p.m., hiking dementia odds by 45 percent.[3] Disruptions may spark brain inflammation or build up harmful plaques.
Sources
https://aging-together.com/seasonal-affective-disorder-in-older-adults-how-to-tell-if-its-more-than-winter-blues/
https://www.monarchseniorliving.com/blog/seasonal-affective-disorder-seniors/
https://www.news-medical.net/news/20260104/Weaker-and-fragmented-circadian-rhythms-linked-to-higher-dementia-risk.aspx
https://corsoatlanta.com/blog/recognizing-the-early-signs-of-dementia-when-to-seek-support/
https://www.heritageseniorcommunities.com/how-can-i-make-the-spring-time-change-easier-on-a-loved-one-with-alzheimers/
https://www.hc-one.co.uk/our-news/blogs-and-articles/sundowning-and-dementia-in-winter
https://greensleevescarehome.co.uk/how-to-spot-winter-blues-in-elderly-loved-ones/
