Twenty-five years ago this month, President Ronald Reagan told the nation he’d been diagnosed with Alzheimer’s disease.

“I now begin the journey that will lead me into the sunset of my life,” he wrote in a letter addressed to his “Fellow Americans,” dated November 5, 1994.

Reagan wrote that he and his wife, Nancy, decided to disclose his condition in hopes that it would increase attention for the disease that slowly, but surely, robs the mind of its memories.

“In opening our hearts, we hope this might promote greater awareness of this condition,” he wrote. “Perhaps it will encourage a clearer understanding of the individuals and families who are affected by it.”

A decade later, in 2004, Reagan succumbed to the illness.

Now, 25 year later, the disease remains just as deadly. It’s currently ranked as the 6th leading cause of death in the U.S., but some research has suggested the true number of Alzheimer’s-related deaths is much higher.

There is still no cure, and no effective treatments for most of the 5.8 million patients currently living with the disease. Only a handful of drugs have been approved to help treat cognitive symptoms.

And much of the research into Alzheimer’s over the past decade has been riddled with disappointment. Early on, autopsies of people with Alzheimer’s disease revealed their brains were full of clumps of protein called amyloid plaques. But experimental drugs meant to target and kill amyloid have flopped and failed in large clinical trials.

While researchers press on with potential pharmaceutical therapies, there is growing evidence that a combination of certain lifestyle factors may help stave off memory decline.

This past summer, scientists reported that people who exercise regularly, refrain from smoking, engage in activities that stimulate their brain and eat a diet rich in fruit, vegetables and healthy oils have a lower risk of developing Alzheimer’s dementia.

The key, researchers said, was to engage in all of those behaviors, not just one. Tight control of blood pressure has also been shown to help delay symptoms of dementia.

What’s more, doctors agree that an early diagnosis can help delay its progression. Signs of a potential problem include:

Changes in mood or personality

Social withdrawal

Confusion with time and place

Difficulty completing daily tasks

Trouble with speaking or writing

It was President Reagan who, 11 years before his own diagnosis, declared November as National Alzheimer’s Awareness Month, a time dedicated to raise awareness for not only the disease, but also, the heavy burden shouldered by those who love and care for patients.

Indeed, Reagan’s 1994 letter also addressed caregivers. “I only wish there was some way I could spare Nancy from this painful experience,” he wrote.

Today, 16 million people provide unpaid care for people with Alzheimer’s or other forms of dementia, according to the Alzheimer’s Association.

The number of people diagnosed with Alzheimer’s disease is expected to swell along with the aging population. The number of those living with Alzheimer’s is projected to soar to nearly 14 million by the year 2050.

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