Longtime and beloved HSBA member, Dan Hogan, heroically confronts Alzheimer’s. His recent diagnosis has spurred his advocacy and activism to help end Alzheimer’s stigma. To learn more about Dan’s efforts to help those with Alzheimer’s, check out his LinkedIn entry at www.linkedin.com/in/danielbhogan .
by Rowan Walrath
April 8, 2024 | A version of this story appeared in Volume 102, Issue 11
It took Dan Hogan more than 10 years to get a diagnosis of Alzheimer’s disease.
Troubled by memory issues in 2012, he went to a doctor who ordered a neuropsychiatric exam. That test told him he was “fine,” he says. So Hogan coasted along through most of his 70s, even though he says he felt his forgetfulness was “a little bit unusual” compared with that of his peers.
Then, when he was 79, a squash tournament threw Hogan’s memory problems into sharp relief.
“I was playing against a 12-year-old. He beat me, and he came up to me after the match and said, ‘Nice match, Mr. Hogan.’ I said, ‘What do you mean, nice match? We just finished the first game,’” Hogan recalls. “And he said, ‘No, Mr. Hogan. I beat you 3 out of 5.’”
Hogan hadn’t remembered most of the games. He hadn’t remembered leaving the court to chat with his children between rounds. Eleven years after he first sought neurological care, the Cambridge, Massachusetts, resident went back to the hospital.
This time, Hogan’s doctor ordered a fluorodeoxyglucose (FDG) positron-emission tomography (PET) scan to look for glucose in his brain and a lumbar puncture to draw cerebrospinal fluid (CSF) to analyze for biomarkers of Alzheimer’s disease. The FDG PET scan was inconclusive, but the CSF analysis wasn’t. Hogan, now 80, has clumps of misfolded proteins called amyloid-β (Aβ) plaques stuck to his brain and is in the early stages of Alzheimer’s disease.
If it had been up to Hogan, he might have discovered that earlier and through a less invasive method. At one point, he looked into some options and came across a diagnostic called PrecivityAD, made by C2N Diagnostics. PrecivityAD runs blood samples through mass spectrometers to measure the ratio of Aβ42 peptides to Aβ40 peptides, as well as levels of a proteotype of the protein apolipoprotein E, which can signify a genetic risk factor for Alzheimer’s disease (Mol. Neurodegener. 2021, DOI: 10.1186/s13024-021-00451-6).
But Hogan says that PrecivityAD, which first arrived in clinics in 2020 and was updated in August 2023, wasn’t on the list of approved tests at Massachusetts General Hospital; PET scans and CSF analyses were. And those tests can take months to schedule and cost thousands of dollars.
“It’s not that easy,” Hogan says. “You can’t just walk in and get a spinal puncture.”
The diagnostic landscape for Alzheimer’s has recently begun to shift, however. Additional noninvasive tests like PrecivityAD are being developed and deployed, in part because of the availability of the only drug proved to slow decline: Eisai and Biogen’s Leqembi. Investors have committed tens of millions of dollars to developing new diagnostics, from simple blood tests to software that analyzes retinal-scan images. Hospital systems are beginning to incorporate some of these tests into their diagnostic workflows.
“I think 2024 will be a turning point in the field of Alzheimer’s disease and will be a time when specialists begin incorporating blood-based biomarkers into their diagnostic evaluation, which has not yet happened in most subspecialty clinics, ourselves included,” Brad Dickerson, a neurologist at Massachusetts General and professor at Harvard Medical School, says in an email. “This will change soon.”
But Dickerson and other physicians warn that it’s too soon to tell whether these tests can stand on their own.
“Sometimes, I think people believe these can replace cognitive testing and a careful assessment,” says Daniel Press, a neurologist at Beth Israel Deaconess Medical Center. “That’s not at all the case.”
More here: https://cen.acs.org/analytical-chemistry/diagnostics/Dementias-next-test-New-Alzheimers/102/i11