ENCINO (CBSLA.com) — Seven years ago, Bob Rosenfield of Encino knew something wasn’t right when he could not find the store he was looking for.

“It was very frightening and very concerning,” he said.

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With his wife by his side, he was eventually diagnosed with dementia, which can be caused by Alzheimer’s.

“You’ve got to address it right away. And if you don’t, you pay the penalty,” his wife, Susan, warned.

Bob got a referral to see Dr. Gary Small, Director of Geriatric Psychiatry at UCLA’s Longevity Center.

Just back from an international conference, he presented his findings that Alzheimer’s and dementia are being undertreated.

“It stems in part from fear of diagnosis – families afraid to come in and get help. And in fact, about half of people suffering from Alzheimer’s Disease don’t even know they have it,” Small said.

According to the UCLA Semel Institute, 4.5 million Americans have Alzheimer’s. There’s a 10-percent chance of developing it if you are over 65 years old. It jumps to 50 percent after age 85.

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The professor of psychiatry and biobehavioral sciences said time lost can mean irreparable damages.

He said medications that have been around for decades are not being taken early and consistently enough to slow down the regression, as patients are sometimes skeptical of results or waiting on a cure.

“The studies show that if you take the medicine, your changes of staying at the same level of functioning in a year are significantly greater than if you don’t take the medicine,” Small explained.

Small said in his experience, early treatment combined with a healthy lifestyle can help patients avoid costly nursing care and stay at home with their families longer.

“It may not cure it. But in the meantime while we’re waiting for science to catch up, there is a lot we can do to help people,” Small added.

Sue Rosenfield credits the aggressive treatment plan and physical activity for slowing down her husband’s regression and hopes other patients can learn from their experience.

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“It’s life-saving and certainly maintaining quality of life,” she added.