FORT LAUDERDALE, Fla. — Arnold Thaler was a corporate executive known for solving problems and jetting to the Far East on business. He was the best man in his son’s wedding, and his wife planned to travel with him in their golden years.

Then Alzheimer’s disease, a neurological condition with no cure and no survivors, took hold of Thaler, 74, and added an unexpected strain on his family.

“Today, he is someone who needs full-time, 24/7 care,” said his son, Scott Thaler, 43, a Fort Lauderdale advertising executive. “He doesn’t have the ability to communicate with any of us anymore.”

The disease’s tolls are crushing to its victims but also devastate the people who love them, the children- and spouses-turned-caregivers, many of whom will mark the holidays under the pall of emotional and financial stress.

As patients progress through the disease, they steadily lose brain function. Their memories flicker and motor skills slip. In later stages, victims lose speech and then the capacity for basic personal care.

Close family members become strangers and, eventually, unpaid home aides.

For these reasons, and because brain diseases are complex, health care for Alzheimer’s patients often becomes a family affair. “One of our rules is a new patient has to come with a family member or a caregiver,” said Dr. Marc Agronin, a geriatric psychiatrist at Miami Jewish Health Systems. “The secret to good care is getting to know both patient and family.”

Kent Barnheiser of the local Alzheimer’s Association chapter and whose parents died from the disease, remembers difficult conversations with his mother. He said she described the horrifying prospect of forgetting “something that she has known her whole life” and feeling like she was “treading water.”

Barnheiser says support groups can be crucial for caregivers to exchange tips and vent frustrations. “When you become a parent to your parents, that’s tough,” he said.