April 7, 2023 -- Michael K, a retired salesman, developed memory problems when he was in his late 60s. At first it was small things, like misplacing his keys or forgetting where he had parked the car. “Senior moments,” he called them. But his wife was concerned and asked him to consult a doctor, who diagnosed him with mild cognitive impairment, or MCI.
Despite his declining memory, Michael continued to enjoy the activities he had always enjoyed, at least for a while. He had always liked hosting, especially making “little spreads”— salads and dips — for his relatives when they came to visit.
“Everyone appreciated how my father made the table look nice for the guests,” said his son Neal, a computer programmer based in New Jersey, who asked that he and his father not be named for this article.
But his father gradually lost interest in these activities, Neal said.
“He stopped being interested in interacting with the family and became more withdrawn," he said.
Eventually, Michael was diagnosed with dementia.
“In retrospect, I think my father’s apathy, together with some other personality changes, were part of the process leading up to his dementia,” Neal said. “We just didn’t realize it at the time.”
Michael’s experience isn’t unique, according to a new study published in the Journal of Alzheimer’s Disease that looked specifically at apathy in people with MCI.
A team of researchers studied 1,092 individuals diagnosed with MCI. The study included slightly more women than men (59%), and participants had an average age of close to 72.
During an 8-year period, the researchers conducted close to 2,900 observations, with people in the study observed between 1 and 9 times (the typical participant was observed twice).
Family members and caregivers completed a questionnaire that asked about an array of symptoms, including apathy, and participants underwent many brain tests.
Of the group, 158 had apathy and 934 did not.
During the study period, close to one-fifth of people converted from MCI to Alzheimer’s disease. Of those who had apathy, 36% developed Alzheimer's, compared to only 14% of those without apathy. The shift to Alzheimer's was also faster in those with apathy compared to those without (an average of almost 4 years vs. an average of almost 7 years).
Those who had apathy showed a 2.4-fold greater risk of conversion to Alzheimer's.
“In older adults with MCI, we found that apathy was a predictor of who would be more likely to develop Alzheimer’s disease,” said senior study author Antonio Teixeira, MD, PhD, professor of psychiatry and head of the neuropsychiatry program at the McGovern Medical School, a part of UT Health in Houston.
Hispanic and Non-Hispanic Ethnicities
Previous research has suggested that apathy may predict progression from MCI to dementia. But these studies were conducted largely in non-Hispanic white people. According to Teixeira and his co-authors, that limits how much we can generalize the findings to other populations.
That's why the researchers studied people enrolled in the Texas Alzheimer’s Research and Care Consortium (TARCC), which includes a significant percentage of Hispanic people, to explore the conversion rates of MCI to Alzheimer’s disease in this population as well.
“A major novelty of our study is that we studied a heterogeneous population with a significant percentage of Hispanic research subjects,” Teixeira said.
Apathy as a 'Red Flag'
Neuropsychiatric symptoms, such as apathy, may be present in as much as 85% of patients with MCI and are also present in the early stages of Alzheimer’s.
Teixeira defined apathy as “loss of interest and reduction in goal-directed behaviors," noting that apathy often goes hand-in-hand with depression and there often is a “huge overlap" but that they aren’t the same thing.
“Depression and disability can add to apathy, but not all people with depression or disability become apathetic,” he said. Conversely, “not everyone with apathy has depression, and apathy can indicate different things.”
Making assumptions about the reason for the patient’s apathy can be problematic because a condition such as Alzheimer’s disease might be overlooked, or the patient might be given incorrect treatment, Teixeira said.
An important take-home message for family members and caregivers is that “apathy in an older adult can be a ‘red flag’ that the person is developing a neurodegenerative condition, such as Alzheimer’s disease,” according to Teixeira.
He advised people involved with the patient’s care to “bring the apathy to the attention of a physician, psychologist, or other health professional” because the presence of apathy “could either prompt further investigation or at least closer following.”
One of Many Factors
Claire Sexton, DPhil, senior director of scientific programs and outreach at the Alzheimer’s Association, said that one of the strengths of this study is that the population is significantly more diverse than the populations in previous studies of apathy, MCI, and Alzheimer’s disease.
"Based on the totality of research, it is still very likely that apathy is only one of many factors that influence the rate of progression from MCI to Alzheimer’s dementia,” Sexton said. The Alzheimer’s Association “believes that it is important for clinicians and family caregivers to monitor for and manage behavioral and neuropsychiatric symptoms, including apathy, throughout the disease course,” which “can be an important part of maintaining or improving everyone’s quality of life," she said.
Neil’s father passed away at the age of 74, by which time the dementia had become very severe.
“I wish we had known more and gotten help for his apathy,” said Neal. “I hope that people reading this article will be more proactive than we were. My father’s quality of life might have been better for longer.”