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BRAIN HEALTH
BRAIN HEALTH

Navigating Dementia: A guide to diagnosis,

treatment and resources in Bexar County

By Arush Shekar
Mild cognitive impairment (MCI) and dementia are broad clinical amyloid and tau, which are now available for clinical practice in specialty
diagnoses that encompass a wide array of underlying neurodegenera- clinics. There is a wide variability in biomarker assay performance, which
tive and non-neurodegenerative causes, with Alzheimer’s disease (AD) providers should consider when ordering biomarkers. Cognitively
being the most common underlying cause. Dementia occurs in more supportive therapies include acetylcholinesterase inhibitors (donepezil,
than one in 10 people over the age of 65, affects one in three people rivastigmine, galantamine) and NMDA receptor antagonists
over the age of 85, and is the most expensive chronic disease in the U.S. (memantine). Two novel anti-amyloid monoclonal antibody therapies,
Significant breakthroughs have recently occurred in dementia clinical lecanemab and donanemab, have now been FDA approved as treatments
care, including identifying potentially modifiable risk/protective fac- for biomarker-confirmed early-stage AD. These monoclonal antibodies
tors, biomarkers to guide precision diagnosis and management, and bind to amyloid beta plaques and clear them from the brain. These
the first disease modifying treatments for AD. therapies have been shown to significantly slow decline, but not to
In Bexar County, dementia affects over 33,000 residents, reflecting reverse symptoms or stop decline. Benefits appear to be greater early in
roughly 13% of the county’s population over age 65. The burden of the disease course. Patients require close monitoring for side effects (e.g.,
the disease extends to those that care for them, with Texas having over amyloid-related imaging abnormalities).
1.4 million unpaid caregivers for patients with dementia. South Texas Vascular dementia refers to dementia primarily caused by cerebro-
has among the highest prevalence of dementia in the U.S., particularly vascular disease, and it is the second most common cause of dementia.
among Hispanic adults, and prior studies have suggested that Hispanic Vascular dementia can present as a gradual or stepwise decline in cog-
adults have a higher risk of developing dementia. As a result of pop- nitive function, and the most common symptoms include difficulty
ulation growth, demographics and aging, San Antonio is anticipated with executive functions, memory retrieval (improves with cue), and
to have a rapidly rising prevalence of dementia, creating a need for irritability. Vascular dementia is estimated to contribute to up to 50%
increased awareness, early detection and access to resources. of all dementias and often co-exists with other causes. Management
focuses on optimizing cardiovascular health, and acetylcholinesterase
Types of Dementia inhibitors are often used for cognitive support.
MCI and dementia are clinical syndromes characterized by a gradual Dementia with Lewy Bodies (DLB) is the third most common form
progressive decline in cognition from an individual’s baseline, which can of dementia, caused by the abnormal buildup and spread of Lewy bod-
be noticed by the individual, a family member and/or a clinical provider. ies, which are aggregations of alpha-synuclein proteins. The disease is
The diagnosis is supported by objective impairment on cognitive testing. marked by fluctuations in cognition, visual hallucinations, parkinsonism
MCI is diagnosed when the individual has preserved independence in and REM sleep behavior disorder. Cognitive symptoms include a pro-
daily functioning and activities, while dementia is diagnosed when the gressive decline in visuospatial, attention and executive function skills.
individual now requires assistance in performing activities needed to live While clinical diagnosis is the mainstay, novel biomarkers are now avail-
independently. The syndromes are most frequently caused by underlying able to test for alpha-synuclein via skin biopsy and cerebrospinal fluid
neurodegenerative diseases. These are diseases that cause chronic, pro- testing. Acetylcholinesterase inhibitors have been shown to improve
gressive loss of neurons, most commonly due to the accumulation and cognition in DLB (often more effective than in AD).
spread of abnormal proteins in the brain. Most patients have multiple Frontotemporal Dementia (FTD) is a heterogenous group of clin-
co-pathologies that contribute to their clinical symptoms. ical syndromes and underlying brain pathologies that cause progressive
AD is the most common cause of dementia, responsible for over degeneration in the frontal and/or temporal lobes of the brain, with asso-
60% of cases. The hallmark brain pathology is extracellular amyloid beta ciated changes in behavior, personality, language and executive function.
peptide plaques and intracellular aggregates of hyperphosphorylated tau FTD is responsible for about 3% of dementia over the age of 65, but over
protein called neurofibrillary tangles. Early clinical signs may include 10% of dementia under the age of 65. The disease is highly heritable, with
difficulty in short-term memory, orientation to time, executive function an autosomal dominant inheritance pattern seen in up to a quarter of all
(planning, organization, problem-solving, complex tasks), visuospatial patients with FTD. One clinical syndrome is behavioral variant FTD
function (getting lost) and word-finding tasks. There are often early (bvFTD), manifesting with early and prominent changes in personality
neuropsychiatric symptoms including irritability, depression, anxiety including disinhibition, apathy, hyperorality and compulsive behaviors.
and/or apathy. There is a growing list of risk/protective factors, with Primary progressive aphasia is another syndrome characterized by early
potentially modifiable factors including vascular disease, hearing/ and prominent loss of language skills. Nonpharmacologic interventions
vision loss, social isolation, physical inactivity and tobacco/alcohol use. and care support are mainstays of treatment, and there is active ongoing
Recent advancements in biomarkers for amyloid and tau have rapidly research to identify biomarkers and treatments.
changed the field, prompting new proposals for biology-based diagnosis Chronic Traumatic Encephalopathy (CTE) is a rare progressive
of AD using new PET, cerebrospinal fluid and/or plasma biomarkers of neurodegenerative disease caused by the accumulation and spread of

16 SAN ANTONIO MEDICINE • June 2025