Bill Gates says there could be a way to predict Alzheimer\'s using a voice app that listens for \'warning signs\'

The road to developing a cure for Alzheimer's has been incredibly rocky. For almost two decades, researchers have conducted clinical trials targeting proteins that lead to the disease, without much luck.

Today, about 5.7 million Americans are living with Alzheimer's. By 2050, that number is expected to jump to 14 million.

In a new blog post, Bill Gates stressed the need for a "reliable, affordable, and easy-to-use" method for diagnosing Alzheimer's early. It's an issue he has personal experience with - Gates' own father was diagnosed with Alzheimer's.

The blog post coincides with the launch of a new research initiative from the Diagnostics Accelerator program at the Alzheimer's Drug Discovery Foundation. The project aims to fast-track technologies that could provide new ways to detect Alzheimer's. A few of the world's most influential billionaires - including Gates and Amazon CEO Jeff Bezos - have donated to the program.

Gates said their investments could help pave the way for apps that can predict Alzheimer's risk using the sounds of our voices.

"I'm excited about a potential future where identifying your risk of developing Alzheimer's is as simple as an app on your phone that you can instruct to listen for warning signs in your speech," Gates wrote.

The idea for a voice app is being pursued by the Framingham Heart Study, a 71-year project that has examined three generations of residents in a single Massachusetts town. The study's audio files of dementia patients could offer insight into their unique vocal patterns, Gates said.

Though speech-pattern diagnosis technology still has to be further developed and proven, it could enable people to detect Alzheimer's early on, when it's easier to treat.

"You might even be able to stop someone from getting Alzheimer's in the first place," Gates wrote.

At the moment, many patients only screen themselves for Alzheimer's after they start showing physical symptoms. But by the time someone is experiencing memory loss or having trouble thinking, they are likely past the early stages of the disease. Alzheimer's can begin damaging the brain a decade or more before symptoms appear, according to the National Institute on Aging.

The Alzheimer's drugs currently on the market offer a band-aid solution for treating those symptoms - including memory loss, impaired judgment, or difficulty speaking - rather than the disease itself.

Doctors can also detect Alzheimer's include a spinal tap or brain scan, but those options are expensive, uncomfortable, and require people to sit still (which can be difficult for an Alzheimer's patient).

But the type of voice app Gates is describing wouldn't solve the problem entirely, since we're still lacking a good way to treat or cure Alzheimer's once a patient is diagnosed.

One of the most promising treatment formulas has been a drug called BAN2401, which has shown potential in decelerating memory loss and reducing the brain plaque that can lead to Alzheimer's. But the companies working on the drug, Biogen and Eisai, have faced skepticism from scientists and investors.

Last month, Biogen and Eisai scrapped two major trials of another drug, called aducanumab, after it no longer seemed to be working.

"The problem is that we don't know what the problem is," neurologist Laura Boylan told Business Insider in March.

Without a better understanding of what causes Alzheimer's, effective treatments could be a long way off.