It was a frigid afternoon with snow still on the ground from a storm the previous day. Mary Williams was in the backyard of her Elmont home. She just went outside for a minute, but that's all it took for her husband Calvin, who has Alzheimer's, to slip away from the house.

Police didn't find him until the next day. He was caught trying to break into a silver Honda Accord - the same make, model and color of the family's car - for warmth. Wearing only a sweater, pants and sneakers - no socks or coat - he had walked for hours and hours. He was found in Brooklyn.

Fortunately, Calvin was not seriously injured and despite initial concerns, there was no frostbite on his body. But the 79-year-old has wandered nearly a dozen times in the last few years and his family, frustrated and tired from his excursions, is worried that if he continues to get out, he won't be so lucky.

Wandering is one of the most common and dangerous behaviors in Alzheimer's patients and also one of the most stressful for caregivers. Mary Ann Malack-Ragona, executive director of the Long Island chapter of the Alzheimer's Association based in Ronkonkoma, said 67 percent of all individuals diagnosed with Alzheimer's will wander during the course of the disease and if the person is not found within 24 hours, serious injuries including death can occur. Every week newspapers across the country report a man or woman turning up dead after wandering away from a home or institution. Some remain missing for years.

Those who wander do so for various reasons. Some leave without a clear purpose, simply lost in their disease-clouded minds or vaguely hoping to find a place to bring them comfort. Others have a goal in mind, such as a house from childhood or a job location from when they were younger.

Because dementia patients are unpredictable in their actions and when found are often unable to give identifying information or home addresses to police, they represent a unique type of "missing person." A woman found wandering in a New Jersey mall spent 15 years in state psychiatric hospitals before officials were able to identify her earlier this year. In April, accusations that Yonkers police mishandled a wandering dementia patient by putting her in a taxi has led to calls in that community for police training and an official policy on dealing with dementia victims.

On Long Island, wandering often includes use of a car or other vehicle, adding yet another level of danger, both to the patient and to others on the road. The issue of when a person with dementia should stop driving - and how to get them to stop driving - present some of the biggest obstacles family caregivers face.

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The articles here explore the topics of wandering and driving, offering information and advice.

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