Panel: Many dementia cases could be prevented

Experts say policies starting in childhood could help at least 35% of sufferers

More than one in three cases of Alzheimer’s disease and other forms of dementia can be traced to factors — such as inadequate education, obesity, hearing loss and smoking — that can be remedied, according to a new report.

These challenges first present themselves in childhood and continue to make their presence felt all the way through one’s senior years. But if all these problems could be fixed, at least 35 percent of seniors who lose their independence and their pasts would instead retain their dignity and their memories until they died of something else, the Lancet Commission on Dementia Prevention, Intervention and Care has concluded.

This would require doctors, communities and governments around the world to implement things like universal preschool and senior visiting clubs; rebuild cities to encourage exercise and healthy diets; and expand preventive health care (along with insurance policies to pay for them). It’s a tall order, the commission acknowledged in a report published recently in the medical journal Lancet. But it would be worth it.

For countries bracing for a tsunami of senior citizens needing wraparound care, a 35 percent reduction in dementia would reduce a crushing burden on productivity, government spending and economic growth.

In 2015, roughly 47 million people were thought to be living with dementia, and $818 billion was spent worldwide on their care. The number of dementia sufferers is expected to triple by 2050, and that growth is likely to be greatest in low- and middleincome countries such as China, India, Brazil and Indonesia.

Dr. Lon Schneider, an Alzheimer’s specialist at the University of Southern California’s Keck School of Medicine and one of the senior authors of the report, said it’s a road map to reducing the global burden of dementia. The avenues it suggests are rarely solutions to dementia alone, he added. Whether the recommendation is to keep children in school, manage high blood pressure in midlife or reduce seniors’ social isolation, such initiatives pay other dividends.

The good news is that many of the world’s most affluent countries — the United States, the United Kingdom, Sweden, Canada, the Netherlands — are already on the right path and have seen unexpected declines in either the number of dementia patients or the rates at which seniors are developing the condition. In most cases, the population’s educational attainment has risen, boosting more seniors’ “cognitive reserve” — and with it their ability to ward off the disabling effects of age-related changes to the brain.

The commission found that stunted educational attainment — specifically, the failure to complete more than eight years of school — is the most potent risk factor for developing dementia. This alone is responsible for 8 percent of one’s lifetime risk for the disease.

The Lancet Commission’s report, unveiled at the Alzheimer’s Association’s international conference in London, followed the presentation of four separate studies showing that stresses that begin in early childhood — including poverty, family fractures, and poor prenatal health care — severely impair brain health in later life. Their cognitive effects are disproportionately seen in African-Americans, the studies found.

The commission found that one of the most powerful, and fixable, drivers of dementia risk is hearing loss. As much as 9 percent of lifetime risk for dementia lies with hearing loss during midlife. Addressing this would dwarf the benefits that could come from other modifiable midlife risk factors, such as managing high blood pressure (which contributes 2 percent of lifetime risk) or reducing obesity (1 percent of lifetime risk).