Weekend sleep-ins won’t undo a bad sleep week, neurologist warns, as dementia damage can start 20 years before memory loss

Subang Jaya, September 18 — Brain alterations related to Alzheimer's disease begin 15 to 20 years prior to visible memory loss, making consistent sleep habits an important and early preventive approach, according to Sunway Medical Centre's Consultant Neurologist, Dr Mohamad Imran Idris.

Dr Imran warns that although one may believe brief sleep deprivation is harmless, persistent poor sleep habits over extended periods can exacerbate brain metabolic stress, expediting neurodegenerative risks. He explains that brain changes can commence 15 to 20 years before the onset of dementia symptoms, meaning significant changes can be observed even 20 years before an individual experiences severe memory issues.

Dr Imran clarifies that people cannot compensate for lost sleep during weekdays by oversleeping on weekends, as sleep regularity is crucial. During deep sleep, the brain naturally eliminates metabolic waste, cellular debris, and inflammation accumulated throughout the day. Chronic sleep deprivation denies the brain this vital recovery period, thereby elevating the risk of cognitive decline over time.

He emphasizes a U-shaped correlation between sleep duration and dementia risk, where the optimal recovery window is seven to eight hours of uninterrupted sleep each night. Excessive sleep can also indicate the early stages of dementia, particularly if an individual begins sleeping significantly more or remains in bed all day, after previously sleeping normally.

Dr Imran highlights that gender plays a significant role in dementia risk, with around twice as many women over 65 living with Alzheimer's disease compared to men. He notes that up to a decade before a formal diagnosis, subtle non-cognitive signs may appear, such as rapid eye movement sleep behaviour disorder, where individuals act out vivid dreams by physically shouting, punching, or kicking during sleep.

In Malaysia, dementia prevalence rises alongside an aging population, with approximately 10 per cent of Malaysians over 60 suffering from the condition, rising to 33 per cent among those aged 80 and above. Nonetheless, Dr Imran emphasizes that modern diagnostics, including blood-based biomarkers and disease-modifying therapies, enable specialists to slow the disease's physical progression.

He suggests that healthier lifestyle changes, such as managing cardiovascular health, remaining physically active, cognitive stimulation, avoiding smoking, reducing air pollution exposure, and maintaining social engagement, can help delay the onset of Alzheimer's symptoms.

If someone notices persistent changes in their sleep patterns or becomes unusually forgetful, Dr Imran urges them to consult a doctor early, as waiting until memory problems hinder recognition of family members is often too late. World Alzheimer's Day, observed globally on September 21, continues to raise international awareness and promote early medical intervention.