It rarely starts with forgetting. A person in their fifties becomes short-tempered, or stops caring about things they used to enjoy, or begins reaching for words that won't come. Families may think they're depressed or stressed. For some people, though, what is actually happening is that the frontal and temporal lobes are dying.
That is frontotemporal dementia (FTD), the leading cause of dementia in people under 65. Unlike Alzheimer's, it takes personality, behavior, and language first, and memory later. And because those early changes look so much like a psychiatric problem, patients can spend years being treated for the wrong thing.
For Hispanic patients, there's a further problem: for a long time, hardly anyone was looking. They have been almost absent from the research on FTD, and absence from the studies is easy to mistake for absence of the disease. Fewer than 5% of participants in the largest U.S. dataset on the disease are Hispanic.
That gap has become self-perpetuating, according to A. Campbell Sullivan, a clinical associate professor of neurology at the Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases. Sullivan said the longstanding assumption that FTD doesn't occur in Hispanic populations has itself become one of the barriers delaying diagnosis.
Sullivan is the senior author of a new study, published in Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring, documenting that Hispanic patients do develop FTD, and that they, too, wait a long time to get an accurate diagnosis. Among the patients studied, an average of four years passed between the first symptoms and evaluation, with delays of up to 10 years.
The study reviewed the case files of 17 Hispanic patients treated in San Antonio. Researchers catalogued the same obstacles again and again: late arrival at specialty care, misattribution to psychiatric conditions, and failure to recognize neurodegenerative disease despite obvious functional decline. Patients were typically referred to neurology only after significant impairment had set in.
Researchers then compared the South Texas cohort with national data, yielding 41 Hispanic and 429 non-Hispanic white participants in all.
On full neuropsychological testing, the two groups turned out to be more alike than different. Scored against norms adjusted for education and testing language, they performed comparably across every cognitive domain. Hispanic patients scored lower on a brief screening test at their first visit, but those screeners weren't education-adjusted, and the Hispanic group averaged two fewer years of schooling.
One difference between the two groups did stand out. On neurological examination, Hispanic patients were more likely to show motor symptoms, including postural instability and apraxia. Non-Hispanic white patients' caregivers, meanwhile, more often reported behavioral changes such as a loss of empathy. Whether that reflects a genuinely different expression of the disease is unclear. Progressive supranuclear palsy, a related neurodegenerative disorder defined partly by balance problems and falls, was also more common in the Hispanic group, which could account for much of the gap.
The study is small, just 41 Hispanic patients, and it was not designed to measure how common FTD is in Hispanic communities. It cannot say whether the rates are higher, lower, or the same. Sullivan and her team say larger cohorts and longer follow-up will be needed to determine whether the differences they found reflect the disease itself or the conditions under which patients finally reach a specialist.
