Larry King's first CNN special, since ending his 25-year reign as Larry King Live host, offered a look into the possible causes of Alzheimer's disease and the race to find a cure.

The one-hour special, "Unthinkable: the Alzheimer's Epidemic," aired May 1 and 8 and included King's tour of Las Vegas' Cleveland Clinic Lou Ruvo Center for Brain Health. King was joined by Ron Reagan Jr., an advocate for awareness of the disease since losing his father, former U.S. President Ronald Reagan, to Alzheimer's in 2004.

"This is something that affects all of us," Reagan Jr. told King in the special. "The odds of either getting the disease or having to be a caretaker for somebody who has the disease are pretty good."

An estimated 5.4 million people have been diagnosed with the disease, and it is now the sixth-leading cause of death in the United States. Nationwide, there are an estimated 15 million people caring for loved ones suffering from Alzheimer's disease.

While at the Cleveland Clinic Lou Ruvo Center for Brain Health, King underwent a brain scan and memory exam testing his risk of developing Alzheimer's. He then talked to Dr. Jeffrey Cummings, director, and Larry Ruvo, CEO and philanthropist, about the disease and how they are treating patients.

Alzheimer's disease is the result of an abnormal accumulation of proteins in the brain, which leads to cell death, but doctors still have not discovered the cause or cure.

The physicians and staff at the Center are actively working toward the development of new, powerful treatment options, and ultimately, a cure. Meanwhile, they provide state-of-the-art care to patients and support for caregivers. Cleveland Clinic Lou Ruvo Center for Brain Health also includes services for patients with cognitive impairment, Parkinson's disease, Huntington's disease and Multiple Sclerosis.

For more information, visit www.ClevelandClinic.org/BrainHealth.

Photo: Larry King, Larry Ruvo and Ron Reagan Jr. at the Cleveland Clinic Lou Ruvo Center for Brain Health