How your body clock can influence your risk of dementia |
Imagine if there were no clock? Without the concept of time, daily life would lose its structure and purpose. Just like that, your body’s clock plays a crucial role in your physical and mental well-being. If your body’s internal clock, known as the circadian rhythm, falls out of sync, it might cause more harm than you think. A recent study published in the journal Neurology found that the body’s clock may influence the risk of dementia.
What is dementia?
Dementia is an umbrella term for several diseases that affect memory, thinking, and the ability to perform daily activities. It is a progressive neurological condition, which means it worsens with age and severely affects the quality of life. According to the World Health Organisation, 57 million people had dementia worldwide in 2021.
Circadian rhythm and dementia
The new study found that circadian rhythms that are weaker and more fragmented are linked to an increased risk of dementia. The study also found that circadian rhythm levels that peaked later in the day, rather than earlier, were also linked to an increased risk. What is a circadian rhythm? Circadian rhythm is the body’s internal clock. It regulates the 24-hour sleep-wake cycle and other body processes like hormones, digestion and body temperature. It is guided by the brain and influenced by light exposure.Having a strong circadian rhythm means the body clock aligns well with the 24-hour day and sends clear signals for body functions. Those with a strong circadian rhythm have regular times for sleeping and activity, even with schedule or season changes. On the other hand, in those with a weak circadian rhythm, the light and schedule changes are more likely to disrupt the body clock. Such people are more likely to shift their sleep and activity times with the seasons or schedule changes.“Changes in circadian rhythms happen with aging, and evidence suggests that circadian rhythm disturbances may be a risk factor for neurodegenerative diseases like dementia. Our study measured these rest-activity rhythms and found people with weaker and more fragmented rhythms, and people with activity levels that peaked later in the day, had an elevated risk of dementia,” study author Wendy Wang, MPH, PhD, of the Peter O’Donnell Jr. School of Public Health at UT Southwestern Medical Center in Dallas, Texas, said.
What did they find?
To understand the impact of circadian rhythm on the brain, the researchers studied 2,183 people with an average age of 79 who did not have dementia at the start of the study. 24% of the participants were Black people, and 76% were white people. They were asked to wear small heart monitors that adhere to the chest to measure rest and activity for an average of 12 days. The strength and patterns of their circadian rhythms were monitored this way. These participants were then followed for an average of three years, and during that time, 176 people were diagnosed with dementia.They found that a total of 31 of 728 people in the high group developed dementia, compared to 106 of the 727 people in the low group. After adjusting for factors such as age, blood pressure and heart disease, researchers noted that when compared to people in the high group, those in the low, weaker rhythm group had nearly 2.5 times the risk of dementia, with a 54% increased risk of dementia for every standard deviation decrease in relative amplitude.They also found that people who had a peak of activity later in the afternoon, 2:15 p.m. or later, compared to earlier in the afternoon, 1:11 p.m.-2:14 p.m., had a 45% increased risk of dementia. 7% of those in the early group developed dementia, compared to 10% of those in the high group.“Disruptions in circadian rhythms may alter body processes like inflammation, and may interfere with sleep, possibly increasing amyloid plaques linked to dementia, or reducing amyloid clearance from the brain. Future studies should examine the potential role of circadian rhythm interventions, such as light therapy or lifestyle changes, to determine if they may help lower a person’s risk of dementia,” Wang said. So, yes, your body’s internal clock could do more than disrupt your sleep.Note: The information provided in this article is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare professional before starting any new medication or treatment, or before changing your diet or supplement regimen
