It is common to feel apprehension regarding dementia, especially when loved ones begin to forget significant names and dates. A recent study, published in the journal Neurology, has identified two additional, rather surprising, potential early warning signs of dementia. These findings suggest that while classic symptoms remain crucial, being aware of these new indicators can facilitate earlier diagnosis and intervention.

The research involved tracking nearly 2,200 adults, with an average age of 79, who were initially free of dementia. Each participant wore a heart monitor for approximately 12 days to record their rest, activity levels, and circadian rhythms. Following this initial monitoring period, researchers continued to observe them for roughly three more years, during which 176 participants received a dementia diagnosis.

Lead study author, Wendy Wang, MPH, PhD, an assistant professor at the Peter O'Donnell Jr. School of Public Health at UT Southwestern Medical Center, and Clifford Segil, DO, a neurologist at Providence Saint John’s Health Center, contributed their expertise to the study's interpretation. The scientists utilized the heart monitor data to ascertain participants' active periods and their daily circadian rhythms. A key discovery was that individuals with weaker internal clocks exhibited a higher risk of developing dementia. This was measured by 'relative amplitude,' which quantifies the difference between a participant's most active and least active times of day. A higher relative amplitude indicated a stronger, more clearly defined daily circadian rhythm.

Furthermore, the timing of peak daily activity also proved significant. Participants whose activity peaked at 2:15 p.m. or later faced a higher risk of dementia compared to those whose activity peaked between 1:11 p.m. and 2:14 p.m. Specifically, about 7% of individuals in the earlier peak group developed dementia, contrasted with 10% in the later peak group. This activity encompassed any form, from daily chores to intentional exercise, and the later group included individuals who were highly active even in the evening, such as 9 p.m.

The exact reason for the link between irregular body clocks and a higher risk of dementia remains unclear. Dr. Wang emphasized that the study observed an association, not causation, and that further research is essential to explore this connection. However, Dr. Segil noted that it is common for dementia patients to struggle with maintaining regular body clocks. He explained that irregular daytime and nighttime activities can disrupt various bodily rhythms, including sleep and hormone release. Patients with dementia frequently report disturbed sleep patterns, such as difficulty initiating or maintaining sleep, which in turn interferes with natural circadian rhythms.

The phenomenon of being active later in the day is also likely connected to disrupted circadian rhythms, which can negatively impact sleep, as highlighted by Dr. Wang. She suggested that a later time of peak activity might indicate a discrepancy between an individual's internal body clock and external environmental cues, a challenge often faced by dementia patients. Dr. Segil clarified that these findings do not imply that a preference for later-day exercise or a 'night owl' tendency predetermines dementia. Instead, he views it as an additional indicator that a person’s circadian rhythm may be imbalanced, particularly if their activity patterns have shifted from earlier in the day, as exercise is typically a more natural daytime activity.

While researchers are still working to fully understand the causes of dementia, existing data suggests that certain lifestyle habits can help mitigate the risk. Dr. Segil recommended maintaining a structured daily routine with regular activities and practicing good sleep hygiene, which he believes can contribute to healthy aging and provide protection against dementia. Additional research supports that having a strong sense of purpose in life, engaging in regular exercise, and adhering to the MIND diet can also reduce one’s risk.

It is important not to panic if your routine is currently disrupted. However, if you observe that a loved one is experiencing increased forgetfulness alongside an unexplained shift in their normal daily routine, it warrants closer attention and a discussion with a healthcare professional.