Lewy Body, vascular, frontotemporal: how the dementias actually differ.
"Dementia" is a family of diseases, not a diagnosis. The specific type shapes medication safety, prognosis, care approach, and what a family should expect. Here's the plain-English guide from a Houston nurse who has cared for families across every type.
Reviewed Apr 2026 · By Andrew Harris, RN · Owner & Clinical Director · Former Neuro ICU Nurse, Houston Methodist Hospital
Why the specific diagnosis matters
- Medication safety. Lewy Body reacts dangerously to some antipsychotics; the wrong prescription can trigger neuroleptic malignant syndrome, a medical emergency.
- Prognosis. Vascular dementia tends to progress in steps; Alzheimer's progresses steadily; FTD progresses fast in the behavioral variant. Planning depends on the trajectory.
- Care approach. Alzheimer's benefits from routine and cues. FTD needs behavior management and family support. Lewy Body needs fall prevention from day one. One-size-fits-all care is not enough.
- Family expectations. Knowing the specific diagnosis lets families anticipate what's coming rather than being blindsided by symptoms that don't fit an Alzheimer's script.
- Access to trials. Some clinical trials at Baylor College of Medicine, UT Health, and other Houston centers require a specific diagnosis for enrollment.
The five dementia types Houston families see most
Alzheimer's disease
Prevalence: 60-80% of dementia cases
Progressive memory loss, especially recent events. Word-finding trouble. Getting lost in familiar places. Slow, steady decline over 5-15 years.
Typically 65+; earlier onset (50s-60s) does occur.
Amyloid plaques and tau tangles visible on PET; hippocampal atrophy on MRI.
Structured routines, environmental consistency, cognitive engagement in moderation. Reasonable response to cholinesterase inhibitors (donepezil, rivastigmine) in early-to-moderate stages. Care plan can lean on predictability.
Vascular dementia
Prevalence: 5-10% of dementia cases (higher when combined with Alzheimer's)
Stepwise decline (function drops after a small stroke, plateaus, drops again). Slower thinking. Trouble with planning and organizing. Physical symptoms (weakness, gait changes) common early.
Typically 60s+; correlated with cardiovascular risk factors.
MRI shows small strokes (silent infarcts) or white-matter disease.
Care plan must include vascular risk management (blood pressure, diabetes, cholesterol control). Fall risk higher. Sudden changes in function are a red flag for a new stroke, not sundowning. Faster clinical response saves function.
Lewy Body dementia
Prevalence: 5-10% of dementia cases (widely under-diagnosed)
Visual hallucinations (well-formed, often of children or animals) in early stages. Fluctuating alertness (great morning, foggy afternoon). Parkinson-like movements: tremor, stiffness, shuffling gait. REM sleep behavior disorder (acting out dreams) often precedes diagnosis by years.
Typically 60s-70s.
Dopamine transporter (DaT) scan often abnormal.
CRITICAL: many typical antipsychotics (haloperidol, risperidone) cause severe, sometimes fatal reactions. If antipsychotic use is being considered, the physician must know this is Lewy Body. Cholinesterase inhibitors often work well. Fall prevention is a top priority from day one.
Frontotemporal dementia (FTD)
Prevalence: 5-10% of dementia cases; the most common dementia diagnosed under age 60
Personality change (loss of empathy, disinhibition, impulsivity) is often the FIRST symptom, before memory loss. Language variants: struggling to name objects, or speech becoming effortful. Memory is often relatively preserved in early stages, which is what makes this dementia so easy to miss.
Often 40s-60s. Family history common.
MRI shows atrophy in frontal and/or temporal lobes.
Behavioral variant FTD is the most challenging for families because the person may seem 'like themselves' cognitively but no longer acts like themselves emotionally. Standard Alzheimer's care approaches don't fit well. Support networks and family respite become critical early.
Mixed dementia
Prevalence: Extremely common in people over 80. Post-mortem studies find pathologies of two or more dementia types in about half of clinical Alzheimer's cases.
Mix of Alzheimer's + vascular is the most common combination. Symptoms overlap.
80+.
MRI shows both hippocampal atrophy and vascular disease.
Care plan needs both memory-support techniques (routines, cues, engagement) AND vascular risk management. Sudden functional changes should be evaluated by a physician; don't assume 'that's just the dementia progressing.'
Red flags: symptoms that mean it is not just Alzheimer's
- Recurrent, detailed visual hallucinations (of people, children, or animals) — evaluate for Lewy Body, do NOT assume 'they're just confused.'
- Personality changes preceding memory loss — evaluate for FTD, particularly if the person is under 65.
- Sudden step-drop in function (over hours or a day) — evaluate for stroke or delirium, not sundowning.
- Acting out dreams / thrashing in sleep — a strong Lewy Body precursor, sometimes appearing years before cognitive symptoms.
- Fluctuating alertness (great morning, foggy afternoon) that's not explained by sundowning environmental factors — evaluate for Lewy Body.
- Progressive difficulty naming familiar objects while memory seems fine — evaluate for primary progressive aphasia (an FTD variant).
Where to get a proper diagnosis in Houston
A proper dementia workup should include: cognitive testing (Montreal Cognitive Assessment or similar), a physical exam, medication review, blood work (to rule out reversible causes like B12 deficiency, thyroid disease, syphilis), and brain imaging (MRI is standard; PET or DaT scan when indicated). Houston has several dementia-specialty centers:
- Houston Methodist Neurological Institute (Cognitive Neurology)
- Baylor College of Medicine Alzheimer's Disease and Memory Disorders Center
- UT Health Houston Neurocognitive Disorders Center
- Memorial Hermann Mischer Neuroscience Institute
A general primary care physician can order the initial workup, but for a definitive typing (especially to differentiate Lewy Body, FTD, or mixed dementia), a referral to one of the specialty centers above is worth pursuing.
What we do differently at Homewatch based on the diagnosis
Every dementia care plan we design at Homewatch of Houston Galleria starts with confirming the specific diagnosis with the family and the physician. If it is Lewy Body, we flag antipsychotic risk in writing to the family and pharmacist, and we plan for fall prevention from day one. If it is FTD, we add family respite hours because the behavioral variant burns family caregivers out fast. If it is vascular, we build cardiovascular monitoring into the daily rhythm and train the caregiver to recognize new stroke symptoms. The care that fits Alzheimer's does not automatically fit the others.
Keep reading
The full dementia handbook
Stages, sundowning, and everything we know about supporting a person with dementia at home.
Chapter IISundowning: what to do when the day turns
The late-afternoon checklist and four environmental fixes that calm 80% of episodes within a week.
ServiceNurse-supervised dementia care
How our clinical team actually staffs a dementia home.