His loved ones dreaded what might be next: a diagnosis of Alzheimer's.
Martin Rosenfeld had called too many times - confused and frustrated - from a parking lot outside his synagogue, after driving there in the middle of the night for services that wouldn't begin for hours.
Once a meticulous pattern-maker in the clothing industry, he now nodded off mid-conversation. Spilled things. Mumbled.
"We'd be getting calls all night long. He'd say, 'What time is it? Can I get up now?' " said his daughter, Shelley Rosenberg, whose husband, Don Rosenberg, chairs the Alzheimer's Association's Greater Michigan Chapter.
Rosenfeld's confusion, which turned out to be caused partly by sleep apnea, reflects what the head of Wayne State University's Institute of Gerontology worries is a growing trend in the number of Americans being wrongfully assumed - even medically misdiagnosed - to have Alzheimer's, the most common form of dementia and perhaps the most feared disease of old age.
"It's a real problem. If you're older and you get a label of Alzheimer's - even a hint that you have Alzheimer's - there's no more critical thinking about it. You're written off by a lot of people," said Peter Lichtenberg, head of the institute and a clinical psychologist who has testified in several probate cases in which a person's mental capacity was at issue.
Lichtenberg, in a December paper for the journal Clinical Gerontology, highlighted two case studies: in one, a man's bouts of confusion and agitation in his late 70s were caused by illness and painful cellulitis, not Alzheimer's; in the other, an 87-year-old woman, who seemed suddenly confused, was suffering from depression.
Lichtenberg's paper builds on research elsewhere that suggests that the difficulty in pinning down Alzheimer's makes misdiagnosis too easy. The research is based mostly on small studies but also on an ongoing, long-term study supported by the National Institute on Aging, which is part of the National Institutes of Health. In cases reviewed so far, about one-third of Alzheimer's diagnoses were incorrect, according to the lead researcher, Lon White.
"The diagnosis was dead wrong one-third of the time, and it was partially wrong a third of the time, and it was right one-third of the time," White said.
The project, called the Honolulu-Asia Aging Study, has been under way since 1991 and focuses on the precise brain changes linked to Alzheimer's disease and other types of dementia. Pathologists examined the brains of 852 men born between 1900 and 1919, about 20 percent of whom were diagnosed with Alzheimer's.
In the cases carrying an Alzheimer's diagnosis, two-thirds of the brains exhibited the types of lesions closely linked to Alzheimer's. Half of those featured other problems, as well, such as scarring on the hippocampus, the part of the brain responsible for memory, White said.
That didn't mean that those without the Alzheimer's lesions were otherwise healthy, "but what we're calling Alzheimer's is very often a mixture of different disease processes," White said.
Lichtenberg said his concerns about misdiagnosis in no way lessen the enormity of Alzheimer's impact.
"I don't know how vast a problem it is, but I see it too often," Lichtenberg said.
The Alzheimer's Association estimates that 5.4 million Americans are living with Alzheimer's. Lichtenberg's grandmother had the disease. A picture of her, dancing, sits in his office at Wayne State.
But understanding how often Alzheimer's and other dementia are misdiagnosed is hard to quantify. Sometimes, that's because loved ones have not yet noticed a decline; sometimes, they don't want to face the possibility, Lichtenberg said.
Rosenfeld's most pressing problem was severe sleep apnea that had aggravated the more manageable symptoms of undiagnosed Lewy-body dementia. Lewy-body dementia causes a visual processing disorder, disrupts the ability to organize, plan and focus, and can causes sleep problems and hallucinations.
A breathing machine at night made a dramatic difference, said Shelley Rosenberg: "I'm thrilled. He is what he used to be. I have my father back."
It's a difficult balance for the Alzheimer's Association: trying to raise awareness and boost early intervention efforts for Alzheimer's and other dementias while also cautioning families and clinicians not to jump to conclusions.
Diagnosing Alzheimer's is tricky and is done, in part, by ruling out other health problems, such as an undetected stroke or brain tumor.
An evaluation by an interdisciplinary team that includes a geriatrician and neurologist is crucial.
"The brain is not just a physical structure. It's this incredible computer. It's constantly computing where resources are needed and redirecting, depending on where the energy is coming from and what task you need to do," said Rhonna Shatz, director of Behavioral Neurology at Henry Ford Hospital in Detroit.
For that reason, a common urinary tract infection, a sudden change in blood pressure or depression are all stresses on an older brain that, combined with other problems, can quickly short-circuit it, Shatz said.