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Alzheimer’s Disease. By: Carla Alexander, 4 th Year Pharmacy Student March 17 th , 2011. Overview. Definition Prognosis Pathophysiology Symptoms Treatment Functional Tests Exceptional Drug Status . Types of Dementia. Dementias: Alzheimer’s Disease Vascular Dementia
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Alzheimer’s Disease By: Carla Alexander, 4th Year Pharmacy Student March 17th, 2011
Overview • Definition • Prognosis • Pathophysiology • Symptoms • Treatment • Functional Tests • Exceptional Drug Status
Types of Dementia • Dementias: • Alzheimer’s Disease • Vascular Dementia • Mixed Type Dementia • Frontal Lobe Dementia • Dementia with Lewy Bodies • Most common form of dementia is Alzheimer's Disease (50-75%)
Definition • An acquired impairment in intellectual function, involving at least three of the following: • Memory • Emotion • Language • Eye-hand skills • Executive function (planning or completing activities • Impairment of cognitive function is sufficient to interfere with normal daily activities.
Characteristics of Alzheimer’s Disease • Chronic • Progressive neurodegenerative disorder • No cure to halt progression • Rate of failure is variable for each person • Prognosis: • Lasts 3-20years (4.5 yrs avg.) • Body is weakened by inactivity, muscle wasting and decreased immune function • Death usually due to secondary infection, such as pneumonia
Statistics • Significant impact on society economically. • Today, half a million Canadians have Alzheimer's disease or a related dementia. • 1 in 11 Canadians over the age of 65 currently has Alzheimer's disease or a related dementia. • One Canadian every five minutes will develop dementia this year. By 2038, this will become one person every two minutes • If nothing changes, the number of people living with Alzheimer's disease or a related dementia is expected to more than double
Pathophysiology • Not a normal part of aging • Acetylcholine (Ach) is crucial for nerve to nerve communication • Depleted in Alzheimer’s Disease • Protein plaques (amyloid, A-Beta) & neurofibrillary tangles (tau) • Normally present in brain • Over production and accumulation in Alzheimer’s Disease • Toxic to nerve cells • Nerve cells die and their connections with other nerve cells are lost; brain cells continue to die over time • Damage starts 10+ years before symptoms
Nerve cell damage due to amyloid beta protein and tau protein. Decreased ability to transmit signals in brain. Decreased concentration of Ach, used for nerve communication.
Symptoms • Three interrelated aspects: • Memory • Perception • Thought • As the disease progresses, a person will experience new symptoms and an increase in the severity of older symptoms • Loss of memory affects perception of events which affects thinking; thoughts not remembered, which then affects your behaviour
90% of patients have behavioural and psychological symptoms • Currently, once an ability is lost, it won’t return.
Causes • No known, single cause of Alzheimer's disease. • However: • Inherited (Genes – APOEe4) • Head injuries • More frequent in women
Diagnosis • True diagnosis can only be found post mortem • Rule out treatable causes • Physical exam • Cognitive tests (MMSE, clock drawing, FAQ) • History • Nurse observations • Blood work • Brain Imaging (MRI, CT)- to detect shape and volume of brain regions
Rule out Treatable causes • Rule out if pain is underlying problem • As seniors age they become still, sore and hurt • People with dementia can’t express themselves very well which triggers agitation • Depression (Pseudo-dementia) • Delirium (drugs, infections-UTI causes delirium) • first check urine • Hypothyroidism • Vit. B12 deficiency • Alcoholism • Drugs & polypharmacy • Hard of hearing
Functional Tests • Cognitive impairment assessed using Mini-Mental State Examination (MMSE) • Orientation, learning, naming, drawing, judgment skills, clock drawing • Functional disability is measured with Functional Assessment Staging Tool (FAST), or Functional Activities Questionnaire (FAQ) • FAQ is required by SK drug plan • Rates 10 routine activities from normal (0) to dependent (3) • Lower the score, the better
Staging Severity • Mild • has trouble with recent memory • have difficulty with certain complex functions such as using the telephone, or managing finances, taking medications or driving • During the mild stage, many people have difficulty controlling their emotions, and so can become irritable and short-tempered. • Moderate • no longer can do complex activities • care for themselves with prompting. • have difficulty learning anything new, they mix up details • begin to move slowly • Suspiciousness, judgment for personal safety is too impaired for them to be counted on.
Staging Severity • Severe • need more and more help with personal care • no longer can control their bowels or bladder • lose weight, and often even lose a sense of who they are • cannot speak in full sentences • delusional, a common delusion is that people are stealing from them; another is that where they live is no longer their house, and they will want to 'go home'. They can mistake their spouse for their mother, or a child for a spouse.
Non-Pharmaceutical Treatments • Often sufficient to make a noticeable improvement in the target symptoms • Distraction • Avoid confrontation, clear and respectful communication • Safe, familiar environment without hazards (prevent falls) • Label items • No diet restrictions; snacks help • Exercise/activity (to avoid muscle wasting) • Soothing music • Sundowning – keep active in day; avoid caffeine • AVOID MAJOR SURGERY & Meds if possible • Reserve drug treatment for situations where non-pharmacological interventions have failed or in situations with dangerous risk,(agitation, hitting).
Pharmacological Treatment • 2 classes of pharmacological agents: 1. Primary meds which attempt to slow the progression • Cholinesterase inhibitors • Memantine 2. Symptomatic meds to manage secondary complications (depend on stage of progression) • Antipsychotics • Antidepressants • Benzodiazepines • Hypnotics • Anxiolytics • Mood Stabilizers • Reevaluate all drug therapies q3- 6 mons to see if still indicated
Primary: Cholinesterase inhibitors • Donepezil-Aricept™ • Rivastigmine- Exelon™ and Exelon ™Patch • Galantamine-Reminyl ER • Work by increasing amount of Ach in the brain to help messages communicate from cell to cell.
Cholinesterase inhibitors • Might slow the decline rate – 3-4% over 6 months • Benefits are small, disease stabilization • No effect on agitation • Trial prescription for ~3months for effect • If don’t respond to one, may help to switch to another • Higher doses have better outcomes • Only work for about 2-3 yrs, then disease progression too much to have benefit • Side-effects • GI issues!, n/v, fatigue, anorexia, decreased heart rate, insomnia, • Expensive ($172-230/month) • EDS coverage • Does not delay institutionalization
Primary: Memantine • Works by blocking glutamate, which at high doses is toxic to cells, therefore stopping cell death. • Small to moderately beneficial effect on cognition, ADL and behaviour • Improvements same as cholinesterase inhibitors (modest) • Future: Combining memantine and cholinesterase inhibitors seems to improve outcomes. Expensive! • Memantine is not on SK formulary
Symptomatic Treatment • Treats the behavioural & psychological component • Hyperactivity = irritable, restless, disinhibition • Mood & apathy = anxiety, depressed, no appetite • Psychosis = delusions, hallucinations, anxiety
Agitation--antipsychotics • 2nd generation antipsychotics: • risperidone (Risperdal) • olanzapine (Zyprexa) • quetiapine (Seroquel) • aripiprazole (Abilify) • Note: no antipsychotics are approved for dementia • Haloperidol (1st generation antipsychotic) not recommended due to side effects (parkinsonism, rigidity etc) • Start low, go slow, keep dose as low as possible
Agitation--Antidepressants May improve aggression, insomnia, depression and psychosis • Start with SSRI (citalopram, sertraline) • Second line venlafaxine • Avoid TCA’s (amitriptyline) due to anticholinergic side effects (confusion, and worsening of Alzheimer’s disease) • Trazodone • Sedating side effect, good for insomnia • Also used to treat sundowning
antidepressants • START LOW, GO SLOW, BUT GO! • Reach adequate dose to relieve symptoms of depression • Trial for 6 weeks, longer to take effect in elderly with dementia • Early improvement indicators: improvement in sleep, appetite and energy, before an improvement in mood
Anxiety—Benzodiazepines (BZD) • BZD caution! Side effects: over sedation, ataxia, altered sleep, falls motor and cognitive impairment • Indicated for agitations, and anxiety especially when other agents fail • Use low doses of short acting agent without active metabolites (lorazepam, oxazepam, temazepam) • Start low, go slow • Not recommended in elderly—last resort • Anxiolytics—buspirone
hypnotics • Sedating antidepressant may be helpful(Trazodone) • Only use hypnotics when absolutely required. • Good alternative is zopiclonevs BZD
Other drugs • Mood stabilizers • Used in agitation, aggression, hostility, sleep wake disturbance, mania • Divalproex 125-750mg daily- fewer side effects • Carbamazepine 100-600mg daily • Betablocker—Propranolol 10-80mg/day • possible decrease in aggression
Pearls • Always rule out treatable cause • Consider 3 mon trial of cholinesterase inhibitor • Re-evaluate meds often (q3-6mons) • If delusions/hallucinations, only treat if a threat to self/others, or interfere w/ care • AVOID POLYPHARMACY– proven that the more pills, the worse they feel and behave • Stop all unnecessary medications • Focus on TLC!
EDS- Cholinesterase inhibitors • Diagnosis of probable Alzheimer’s as per DSM-IV • Mild to moderate stage of disease, with MMSE of 10-26/30, <60 days of application • FAQ <60 days of application • Must discontinue all drugs with anticholinergic activity, at least 14 days before MMSE and FAQ given. • No concurrent anticholinergic therapy. Patients intolerant to one agent may be switched to a different agent. • Current Patients: Require 6 months assessment to continue, must not have both a >2 point reduction in MMSE and a 1 point increase in FAQ. Scores are compared to previous scores. • New Patients: Enter 3 month trial and must exhibit improvement in MMSE and FAQ scoring. RE-evaluate in 6 months as above.
EDS continued: • MMSE must stay at or above 10 throughout treatment • The patient is monitored with these 2 scales (MMSE , FAQ) to ensure treatment is still effective. Once the patient is not responding to the medication (scores worsen with set guidelines, MMSE 2 point reduction, FAQ 1 point increase) coverage is stopped. The risk of treatment then outweighs the benefit and treatment is stopped.
References • Therapeutic Choices, 5th Edition • Alzheimer’s Society of Canada http://www.alzheimers.ca/english • RX Files • Rhett Carbno, College of Pharmacy Lecture Notes on Dementia. • Robert J. Webb, MD. Medical Director, Hospice of the Shoals, and Palliative Care Service, ECM Hospital. Florence, AL. Drugs for Dementia Lecture. March 11-12th, 2011. • Dementia Guide http://www.dementiaguide.com/aboutdementia/typesofdementia/alzheimers