I’m reaching the age where cognitive decline begins to rise dramatically in the general population, so much so that the possibility of succumbing to it preys on our minds. Indeed, aging is the greatest risk factor; but then, that’s a no-brainer (pardon the pun).
Nevertheless, dementia or Alzheimer’s is not inevitable in senior citizens, as many live to ripe old ages with their mental faculties intact. The research behind cognitive decline is intense and has led to a better understanding of factors that impact cognition as a person ages. Data show that the process is multifactorial and that causation may vary among patients. Factors include:
(1) Family history. Risk is increased if one has a family history of cognitive decline.
(2) Genetics. Research has identified a gene, SHMOOSE, that if mutated, increases risk.
(3) Passion, regular exercise and meaningful relationships. A study found that all three of these lifestyle factors promote brain health during the aging process, reducing the level of gray matter (the portion containing neurons) atrophy. Increased social interaction or pursuing one’s passion (such as learning a new language) is linked to better cognitive function and larger brain volume. A number of brain changes were associated with physical activity, including new neuron formation in memory areas, more connections among neurons and increased vascular structure. It was noted that merely walking 4,000 steps per day reduced the risk of mental decline by 25%; increasing steps to 10,000 reduced the risk by 50%.
(4) Sleeping too long or going to bed too early. Getting enough sleep is vital to one’s health. Surprisingly, a new study of older adults in China suggests that sleeping too long (over 8 hours) or going to bed too early (before 9:00 pm) is detrimental to brain health. These results underscore the importance of monitoring sleeping habits of the elderly.
(5) Nightmares. Distressing dreams can become more frequent with age and are associated with disturbed sleep and reduced cognitive function. New research suggests that people ages 35-64 who have at least one nightmare a week may be 4X more likely to experience cognitive decline.
(6) Diet. Levels of six blood metabolites are correlated with cognitive function and are influenced by diet. Results of a study suggested that adherence to healthy diets such as the Mediterranean diet may be beneficial to brain health over a wide age range.
(7) Meal timing. The best plan for maintaining cognitive function is balancing energy intake across three roughly equivalent meals per day. The worst outcome occurs when breakfast is skipped.
So how do “super agers” (those rare people who retain sharp memories well into old age) differ? Researchers at Northwestern University were surprised to find that, upon autopsy, the memory cortex of their brains contained neurons substantially larger even compared to individuals 20-30 years younger, suggesting that they were resistant to age-related shrinking. They also lacked neurons with tau tangles that are characteristic of Alzheimer’s disease.