Alzheimer's: Sleep matters 20 years before symptoms

SUBANG JAYA: Brain changes associated with Alzheimer's disease were found to begin 15 to 20 years before the onset of noticeable memory loss, making long-term sleep hygiene a critical and early preventive measure.

Sunway Medical Centre, Sunway City Consultant Neurologist Dr Mohamad Imran Idris warned that while pulling occasional late nights might have seemed harmless, consistent poor sleep patterns over months and years compounded metabolic stress on the brain, accelerating neurodegenerative risks.

"Changes in the brain start 15 to 20 years before somebody actually develops dementia, meaning 20 years before they start having severe memory problems, you can already see microscopic changes occurring," he told Bernama in an exclusive interview.

Addressing a widespread biological misconception, Dr Mohamad Imran emphasised that individuals could not compensate for or "buy back" lost weekday sleep by oversleeping during weekends.

"Sleep regularity is what matters because pulling four-hour nights and trying to compensate with 12-hour weekend sleep simply does not work biologically to clear accumulated brain inflammation," he explained.

He noted that during deep sleep, the brain actively clears away metabolic waste, cellular debris and inflammation accumulated during waking hours.

Chronic sleep deprivation, he noted, deprives the brain of this essential recovery window, thereby increasing the risk of cognitive decline over time.

Dr Mohamad Imran highlighted a distinct U-shaped correlation between sleep duration and dementia risk, noting that the biological sweet spot for brain recovery was seven to eight hours of uninterrupted sleep per night.

"Too little sleep increases the risk of dementia, but too much sleep can also reflect that someone is already developing it, especially if someone who used to sleep normally suddenly begins sleeping for much longer hours or stays in bed all day," he noted.

In terms of risk demographics, he pointed out that gender played a significant role, with statistics showing there were approximately twice as many women as men over the age of 65 living with Alzheimer's disease.

He further explained that up to a decade before a formal diagnosis, subtle non-cognitive indicators often emerged, including Rapid Eye Movement (REM) Sleep Behaviour Disorder (RBD).

He said this condition involved individuals lacking normal dream-state muscle paralysis, causing them to physically act out vivid dreams through shouting, punching or kicking in their sleep.

In Malaysia, dementia prevalence was shown to be escalating alongside an ageing demographic, with Health Ministry surveys indicating that approximately 10 per cent of Malaysians over 60 suffered from the condition, rising to 33 per cent among those aged 80 and above.

Despite these sobering figures, Dr Mohamad Imran stressed that modern diagnostics, such as blood-based biomarkers combined with newly approved disease-modifying therapies, now allow specialists to actively slow down the physical progression of the disease.

He said that healthier lifestyle changes, such as managing cardiovascular health, staying physically active, cognitive training with stimulation activities to challenge the brain, avoiding smoking, reducing exposure to air pollution, and maintaining social engagement with people around, help in delaying the early onset of Alzheimer's symptoms.

"If you notice a persistent change in your sleeping patterns or are becoming unusually forgetful, see a doctor early, because waiting until memory problems prevent you from recognising family members is often too late," he urged.

World Alzheimer's Day, observed globally every year on Sept 21, continued to serve as a vital platform to raise international awareness and advocate for early medical intervention. — BERNAMA