In nursing homes and EHPADs, Alzheimer's disease occupies a central place in the training of care teams. This is legitimate: it accounts for 60 to 70% of dementia cases in France. However, this omnipresence sometimes creates a clinical blind spot: the Alzheimer's-related diseases — Lewy body dementia, frontotemporal dementia, vascular dementia, progressive supranuclear palsy, posterior cortical atrophy — are frequently underdiagnosed or wrongly assimilated to "classic" Alzheimer's disease.

This confusion is not without consequences. Adapting practices to Alzheimer's disease when actually accompanying someone with Lewy body dementia risks inappropriate medication, poorly targeted stimulation, and a misunderstanding of behaviors that exhausts the team and increases the suffering of the resident. Conversely, recognizing the specificity of each pathology allows for personalized support, prevents avoidable complications, and better supports families.

This guide is aimed at care professionals in nursing homes: nursing assistants, nurses, activity coordinators, psychologists, occupational therapists, care coordinators. It does not replace a medical diagnosis but provides you with the keys to observe, alert, and adapt appropriately on a daily basis.

1. Overview of Alzheimer's-related diseases

The term "dementia" refers to a clinical syndrome characterized by a cognitive decline severe enough to impact daily life. This syndrome can be caused by many different pathologies. Alzheimer's disease is the most common form, but it is far from the only one.

The World Health Organization estimates that around 55 million people live with dementia worldwide, and this number will double by 2050. In France, there are approximately 1.2 million affected individuals. Among them, 30 to 40% have a pathology other than Alzheimer's or a mixed form combining several pathological mechanisms.

The main pathologies grouped under the term "Alzheimer's-related diseases" are as follows:

1. Frontotemporal dementia (FTD) — preferential involvement of the frontal and temporal lobes, often with early onset (50-65 years), marked by behavioral or language disturbances at the forefront.
2. Lewy body dementia (LBD) — the second leading cause of degenerative dementia after Alzheimer's, characterized by a triad: cognitive fluctuations, early visual hallucinations, and parkinsonian syndrome.
3. Vascular dementia — a consequence of cerebrovascular damage (Stroke, lacunes, leukoaraiosis), with a progression often marked by ups and downs and a relative preservation of episodic memory in the early stages.
4. Progressive supranuclear palsy (PSP) — atypical parkinsonian syndrome with vertical oculomotor dysfunction, early postural instability, and frontal dysexecutive syndrome.
5. Posterior cortical atrophy (PCA) — a variant of Alzheimer's with visual onset, spatial disorientation, early praxic disturbances, and agnosia, but with memory preserved for a long time.
6. Creutzfeldt-Jakob disease (CJD) — a rare spongiform encephalopathy, with very rapid progression (weeks to months), presenting polymorphically with cognitive disturbances, myoclonus, and diffuse neurological signs.
7. Mixed forms — very common in the elderly, combining an Alzheimer's component with a vascular or Lewy body component. These forms make differential diagnosis particularly complex.

2. Why distinguishing these pathologies is essential in nursing homes

One might be tempted to think that, faced with a resident in a nursing home whose dementia is advanced, the distinction between Alzheimer's and a related disease matters little: support will anyway be focused on comfort, safety, and quality of life. This reasoning, although intuitively appealing, is erroneous for at least four major reasons.

Vital medication contraindications

Lewy body dementia perfectly illustrates this issue. Classic neuroleptics (haloperidol, chlorpromazine) are frequently prescribed to manage behavioral disorders in Alzheimer's disease. In LBD, they cause severe hypersensitivity reactions, potentially fatal: extreme rigidity, coma, malignant hyperthermia. A hospitalized LBD resident for agitation treated with neuroleptics may not survive. The vigilance of the care team regarding signs indicative of LBD can literally save a life.

Different cognitive stimulation modalities

Standard cognitive stimulation in nursing homes is often modeled on the needs of Alzheimer's disease: episodic memory exercises, fact recall, temporal orientation. This approach is counterproductive, even painful, for a resident with frontotemporal dementia whose episodic memory is long preserved but who presents severe apathy or disinhibition. It is unsuitable for a patient with primary progressive aphasia who can no longer perceive space correctly. Adapting cognitive stimulation to the resident's actual neuropsychological profile is a condition for its effectiveness.

A better understanding of disruptive behaviors

Aggression, disinhibition, and aberrant eating behaviors of a frontotemporal dementia resident are sometimes interpreted as "Alzheimer's agitation" and managed by inappropriate behavioral measures. Understanding that these behaviors are the direct consequence of frontal damage — and not of bad will or anxiety — radically changes the approach. The team can anticipate, structure the environment, and de-dramatize rather than react in urgency.

Better support for families

Families of residents with frontotemporal dementia or LBD are often bewildered by symptoms they had not anticipated. LBD, in particular, affects relatively young people and often presents with personality changes that those around interpret as a "change in character" or a psychiatric problem. A trained team can help the family recontextualize these behaviors within the framework of the disease, which reduces guilt and improves the quality of visits.

3. Frontotemporal dementia (FTD) : when behavior takes precedence

Frontotemporal dementia is a group of degenerative pathologies characterized by a preferential impairment of the frontal and anterior temporal lobes. It differs from Alzheimer's disease by several major clinical features.

An earlier onset

The average onset age of FTD is 58 years, compared to 73 years for Alzheimer's. This difference is fundamental in a Nursing home : a 60-year-old resident with severe behavioral disorders, whose episodic memory remains relatively preserved, should be directed towards FTD rather than atypical Alzheimer's. Care in a traditional geriatric facility is often unsuitable for these younger, more active profiles, with different social needs.

Three main clinical variants

FTD has three main presentations. The behavioral variant (bvFTD) is the most common (50 % of cases). It manifests as disinhibition, apathy, loss of empathy, stereotyped behaviors, changes in eating habits (hyperphagia, preference for sweets). Episodic memory is initially preserved, but executive functions are severely impaired.

The semantic aphasia variant (SV) is characterized by a progressive loss of meaning of words and concepts. The resident speaks fluently but empties their sentences of semantic content (“ thing ”, “ stuff ”, descriptions instead of names). They may no longer recognize famous faces or common objects. The non-fluent primary progressive aphasia (NFPA), the third variant, is characterized by significant speech effort, apraxia of speech, progressive dysarthria with language comprehension preserved for a long time.

What this changes for the caregiving team

When faced with a bvFTD resident, the team should expect disconcerting behaviors : lack of modesty, inappropriate comments, excessive food consumption, rigidity regarding daily rituals. These behaviors are neither malice nor a refusal of authority : they are the direct consequence of frontal disinhibition. The strategy is not confrontation but reorientation and structuring.

4. Lewy body dementia (LBD) : vigilance on treatments

Lewy body dementia is the second leading cause of degenerative dementia, accounting for about 15 to 20 % of cases. It is caused by the accumulation of alpha-synuclein protein in neurons in the form of Lewy bodies, affecting the cerebral cortices and subcortical structures.

The characteristic clinical triad

The diagnosis of LBD is based on three cardinal symptoms. Cognitive fluctuations are significant variations in attention and alertness throughout the day or from day to day : the resident may be clearly awake and communicative in the morning, then prostrate and confused in the afternoon, without apparent reason. These fluctuations are often mistakenly interpreted as simulation or depression.

Early and recurrent visual hallucinations are almost pathognomonic of LBD. They typically involve images of animals, children, or unknown people, often described accurately and relatively calmly by the resident. They may precede cognitive decline by several years. The spontaneous parkinsonian syndrome — rigidity, bradykinesia, postural instability, sometimes tremor — completes the triad.

Major medication risks

One of the most critical issues of LBD in Nursing homes is the extreme sensitivity to neuroleptics. Classic antipsychotics (haloperidol, chlorpromazine) as well as some atypicals (risperidone, olanzapine) can cause in LBD a syndrome of severe sensitivity : abrupt worsening of cognitive disorders, massive rigidity, hyperthermia, stuporous state that can be fatal. This reaction occurs in 30 to 50 % of LBD cases exposed to neuroleptics.

Equally problematic : anticholinergic effect medications (certain antihistamines, tricyclic antidepressants, urinary antispasmodics) are poorly tolerated in LBD and worsen confusion. The care team must systematically alert the coordinating physician before introducing any new treatment for a resident suspected of having LBD.

Appropriate support in Nursing homes

Hallucinations in LBD are rarely anxiety-provoking if one does not seek to "correct" them. The most effective strategy is to not confront the resident about the reality of their visions, but to accompany them in their experience (“Do these people scare you? Would you like us to stay with you?”). Activities should take into account cognitive fluctuations : plan stimulation workshops at times of better alertness, usually in the morning.

5. Vascular dementia: a stepwise progression

Vascular dementia is the consequence of brain damage of vascular origin: multiple infarcts, diffuse subcortical lesions (leukoaraiosis), or sequelae of a strategic stroke affecting a key brain area. It represents about 15% of dementias, but this proportion is likely underestimated due to the frequency of mixed forms.

A clinical presentation distinct from Alzheimer's

Unlike Alzheimer's, whose decline is progressive and regular, vascular dementia often evolves in a stepwise manner: the patient experiences a sudden deterioration at the time of a new vascular event, followed by a period of relative stability, then another decline. This discontinuous progression is an important warning sign.

Episodic memory is often relatively preserved at the onset, unlike in Alzheimer's. It is the executive and attentional functions that are affected first: slow processing, planning difficulties, concentration problems, psychomotor slowing. Associated neurological signs are common: gait disturbances, early urinary incontinence, pseudobulbar syndrome (spasmodic laughter and crying).

Vascular risk factors at the heart of prevention

Vascular dementia is the only form of dementia for which preventive action remains effective even after the first symptoms. Control of vascular risk factors — high blood pressure, diabetes, atrial fibrillation, dyslipidemia, smoking — slows the onset of new lesions and stabilizes the clinical picture. In nursing homes, vigilance regarding blood pressure, anticoagulant treatment in case of fibrillation, and overall therapeutic adherence are integral to care.

Adapting support to the vascular profile

The vascular resident tires quickly and shows great variability in performance depending on the time and conditions. Activities should be short, well-structured, with simple and clear instructions. Stimulation of executive functions — sorting, organizing a task sequentially — is more relevant than episodic memory exercises. Attention to gait disturbances and fall risks is also crucial.

6. PSP, ACM, and other Parkinson-plus syndromes

Progressive supranuclear palsy (PSP)

PSP is an atypical parkinsonian syndrome caused by the accumulation of tau protein in the neurons of the brainstem and basal ganglia. It is distinguished from Parkinson's disease by early and severe postural instability (falls in the early years), a disorder of gaze verticality (difficulty looking down, a nearly pathognomonic sign), and marked dysarthria.

Cognitive disorders in PSP are of the fronto-subcortical type: ideomotor slowing, dysexecutive syndrome, apathy. Episodic memory is initially preserved. Swallowing impairment is a severe and early complication, warranting careful monitoring and rapid adaptation of food texture.

Posterior cortical atrophy (PCA)

PCA is a variant of Alzheimer's in which lesions predominate in the parietal and occipital cortices. The clinical picture is dominated by early and severe visuospatial disorders: inability to locate objects in space, to read, to recognize faces or objects (visual agnosia), to perform complex gestures (apraxia). Memory and language are preserved for a long time, creating a disconcerting gap between the resident's verbal abilities and their functional incapacities.

In nursing homes, the PCA resident is often perceived as "strange" or "a simulator" because they can hold a coherent conversation but are unable to find their room, recognize their plate, or use a spoon. Understanding this neuropsychological profile by the team is essential to adapt the environment (strong visual signage, uncluttered environment, assistance with daily gestures) and avoid paradoxical injunctions.

7. Comparative table: distinctive signs by pathology

This table is a clinical orientation tool, not a diagnostic one. It serves to structure observation and formulate relevant questions for the coordinating physician or neurologist. The formal differential diagnosis relies on a comprehensive neuropsychological examination, neuroimaging (brain MRI), and increasingly, on biomarkers in the CSF or through amyloid PET.

8. Concrete adaptation of care practices

Knowing the different pathologies is necessary but insufficient. The added value of this knowledge is measured in the concrete adjustments it allows on a daily basis. Here is how the specificities of each pathology translate into adapted care practices.

Communication and caregiver-resident relationship

In FTD, the relationship must be firm without being confrontational. The resident is unaware of their inappropriate behaviors (frontal anosognosia): arguing is pointless. The technique of diversion and proposing an alternative activity is more effective. The team must be prepared not to take inappropriate remarks personally.

In AD, cognitive fluctuations make exchanges very variable. The caregiver must adapt to the resident's level of alertness in the moment, not insist during phases of confusion, and resume communication during phases of better clarity. Hallucinations deserve an empathetic, not corrective response ("I don't see the same things you do, but I hear you").

In ACP, verbal comprehension being long preserved, the resident understands what is said to them. However, visual information reaches them distorted. The caregiver must verbally guide each gesture, orally describe what they are going to do, and avoid solely gestural instructions.

Environmental adjustments

For the FTD resident, structuring the environment means reducing uncontrolled stimuli (access to food, freedom to wander in unsuitable areas) while maintaining marked spaces of freedom. Rituals and routines are resources, not constraints: rely on them rather than breaking them.

For the ACP resident, the environment must be visually uncluttered and well marked. Bright color cues on the bedroom door, a clearly defined path to the dining room, contrasting dishware with the tablecloth: these simple adjustments significantly reduce functional disorientation and situations of failure.

For the PSP resident, fall prevention is a priority. The bed must be at a minimum height, the chair must provide good back support to compensate for postural instability, and thick-soled shoes should be avoided. The bedside table and elements of the room must be accessible without the resident having to lower their gaze.

Nutrition and nursing care

Swallowing disorders are early in PSP and late in Alzheimer's. A speech therapy evaluation of swallowing should be anticipated well before the onset of significant aspiration. The texture and consistency of meals must be gradually adapted. Mealtime is also a risk moment for falls in PSP: the resident may tip backward while trying to look at their plate.

In FTD, hyperphagia can be managed in small portions (several small servings) and by offering healthy alternatives freely accessible. Total removal of access to food leads to great agitation; it is better to channel than to prohibit.

9. Stimulation cognitive : quels outils pour quels profils ?

La stimulation cognitive en EHPAD est souvent pensée comme un bloc homogène d'activités bénéfiques pour « les personnes démentes ». La réalité neuropsychologique est bien plus nuancée. Stimuler de façon inadaptée peut être aussi délétère qu'une absence de stimulation : une activité de remémoration pour un résident DFT dont la mémoire est préservée mais dont le comportement est désorganisé aggrave l'agitation sans apporter de bénéfice cognitif. Un exercice de lecture pour un résident ACP sans adaptation sensorielle est une source d'échec et de frustration.

Principes généraux de la stimulation différenciée

Le premier principe est de partir du profil neuropsychologique réel du résident et non du diagnostic seul. Deux résidents DFT peuvent avoir des profils très différents selon la variante et le stade de la maladie. Une évaluation neuropsychologique actualisée, même sommaire, guide plus efficacement le choix des activités qu'un diagnostic de cinq lettres.

Le deuxième principe est de cibler les fonctions préservées autant que les fonctions déficitaires. La stimulation des capacités résiduelles maintient l'estime de soi et l'engagement motivationnel. Un résident DCL peut avoir des capacités musicales longtemps préservées (mémoire procédurale musicale) : la musicothérapie est un levier puissant. Un résident DFT variante sémantique peut bénéficier de travaux manuels qui font appel à la mémoire procédurale plutôt qu'au langage.

Le numérique comme outil de stimulation adaptable

Les outils numériques de stimulation cognitive présentent un avantage considérable pour les maladies apparentées à Alzheimer : la modularité fine des exercices. Là où un atelier papier-crayon propose un niveau de difficulté fixe, une application sur tablette peut adapter en temps réel la complexité, le nombre de distracteurs, le temps de réponse autorisé et la modalité de présentation (visuelle, auditive, combinée).

Pour un résident DCL, les exercices peuvent être programmés aux plages horaires de meilleure vigilance, avec des sessions courtes (10-15 minutes) et une interface simple. La tablette génère des données de suivi qui permettent d'objectiver les fluctuations cognitives : un graphique de performance sur plusieurs semaines montre clairement les variations, ce qui aide le médecin à ajuster la prise en charge.

Pour un résident DFT variante comportementale, les exercices centrés sur les fonctions exécutives (classement, séquençage, catégorisation) sont plus pertinents que les exercices de mémoire épisodique. Les activités courtes avec feedback immédiat maintiennent l'attention mieux que les tâches longues et ouvertes. La tablette offre également un cadre contenant qui structure la session et réduit les comportements d'errance ou de distractibilité.

Pour un résident ACP, les exercices doivent minimiser les tâches visuospatiales et valoriser la compréhension verbale et le langage. Les exercices d'écoute, de compréhension orale, de fluence verbale et d'évocation sémantique sont adaptés. La taille des éléments visuels sur l'écran doit être maximisée et les contrastes renforcés.

10. Travailler en équipe pluridisciplinaire autour du diagnostic différentiel

La reconnaissance et l'accompagnement différencié des maladies apparentées à Alzheimer ne peuvent pas reposer sur un seul professionnel. C'est un travail d'équipe, structuré autour d'une culture commune, d'outils de transmission partagés et d'une organisation qui valorise et exploite les observations du terrain.

Le rôle clé de l'observation quotidienne

Les aides-soignants, les ASH, les animateurs et les aides médico-psychologiques sont en contact direct et prolongé avec les résidents. Ils sont les premiers à percevoir les signes d'alerte : fluctuations inhabituelles, comportements nouveaux, hallucinations, chutes atypiques. Mais cette observation ne vaut que si elle est transmise, formalisée et prise en compte.

Une grille d'observation simple et partagée — listant les signes distinctifs des principales pathologies — permet à tout soignant, quelle que soit sa qualification, de contribuer à l'affinement du tableau clinique. Ces observations doivent être notées dans le dossier de soin avec la date, l'heure, le contexte et le comportement observé précisément décrit. « Agitation dans la soirée » est insuffisant. « À 20h30, a interpellé plusieurs fois des personnes absentes, semblait voir quelqu'un dans le couloir, a été calmé par la présence silencieuse d'une soignante pendant 10 minutes » est exploitable cliniquement.

La réunion de synthèse pluridisciplinaire

La réunion de synthèse est le lieu où les observations du terrain deviennent des décisions thérapeutiques. Pour qu'elle joue ce rôle dans le diagnostic différentiel, elle doit intégrer un temps dédié à la révision des hypothèses diagnostiques. Un résident admis avec un diagnostic d'Alzheimer présumé peut, au fil des mois, montrer des signes évocateurs d'une DCL ou d'une DFT. La réunion de synthèse est l'occasion de formuler ces questions et d'en référer au médecin coordonnateur ou de solliciter un avis neurologique.

La formation continue de l'équipe joue un rôle central. Une équipe qui connaît les signes cliniques des principales pathologies observe différemment. Elle formule des hypothèses, pose des questions, et contribue à un tableau clinique plus précis. Cette compétence collective améliore directement la qualité des soins et la sécurité des résidents.

Le médecin coordonnateur et le neurologue

Le médecin coordonnateur est la charnière entre les observations de l'équipe soignante et les décisions médicales. Son rôle est d'intégrer les données cliniques, de solliciter des bilans complémentaires si nécessaire, et d'informer l'équipe des implications pratiques du diagnostic. Un diagnostic différentiel formalisé — « ce résident présente une DCL, neuroleptiques formellement contre-indiqués, adapter les horaires d'activité aux fluctuations » — traduit la clinique en directives concrètes pour l'équipe.

La télémédecine permet désormais, dans certains territoires, d'obtenir un avis neurologique spécialisé sans déplacer le résident. Ces dispositifs facilitent l'accès à une expertise difficile à obtenir en zone rurale et permettent une révision des diagnostics sans hospitalisation longue et déstabilisante pour le résident.

Soutenir et former les équipes en continu

L'accompagnement de résidents atteints de DFT, de DCL ou de PSP est exigeant sur le plan émotionnel. Les comportements désinhibés, les hallucinations, la lenteur extrême du résident PSP, les fluctuations déconcertantes de la DCL — tout cela sollicite des ressources psychologiques importantes chez les soignants. La formation ne suffit pas si elle n'est pas accompagnée d'un espace de parole et d'analyse des pratiques.

La supervision d'équipe, les groupes de parole animés par un psychologue, et les formations courtes ciblées sur des situations concrètes permettent de transformer la connaissance théorique en compétences pratiques solides et durables. Les soignants qui comprennent pourquoi un résident DFT se comporte ainsi ne vivent pas cet accompagnement de la même façon que ceux qui l'interprètent comme de la mauvaise volonté.

Comprendre les maladies apparentées à Alzheimer dans leur singularité clinique, c'est redonner à chaque résident l'accompagnement qui correspond précisément à ce qu'il vit dans son cerveau et dans son corps. C'est aussi redonner aux équipes soignantes un cadre de compréhension qui transforme des comportements perturbants en signes cliniques intelligibles — et les soignants démunis en professionnels compétents et serein. Cette compétence s'acquiert, se partage et s'entretient. Elle est au cœur de la qualité de vie en EHPAD.