SELECTED GERIATRIC NEUROLOGIC DISEASE Module 1 Parkinsons disease

SELECTED GERIATRIC NEUROLOGIC DISEASE Module 1 Parkinson’s disease Bill Lyons, M. D. UNMC Geriatrics Asst. Professor wlyons@unmc. ed u

OVERVIEW • Parkinson’s disease • Other movement disorders • Stroke and TIA

Objectives Re: Parkinson’s disease, upon completion the learner will be able to; 1. List the diagnostic characteristics 2. Describe the key pathologic features 3. Describe evaluation and management 4. List the most common complications

PARKINSON’S DISEASE • Prevalence increases with age (starts 40 s 60 s) • Seen in all ethnic groups, M: F about 1. 5: 1 • Second most common neurodegenerative disease • Genetics’ role greater when younger onset • CO poisoning, rural residence, pesticide or herbicide exposure, MPTP, encephalitis

Nigrostriatal Dopaminergic Neurons Striatum Substantia nigra

Substantia nigra, Normal Substantia nigra, PD

CARDINAL FEATURES OF PARKINSON’S DISEASE • TRAP (any combination) • Tremor • Rigidity • Akinesia/Bradykinesia • Postural instability • Onset usually asymmetric • Diagnosis clinical

TREMOR OF PARKINSON’S • • Rest, 3 -6 Hz, pill-rolling Emotional stress may exacerbate Inhibition by movement or sleep Absent in ~20%

BRADYKINESIA • • Slowed voluntary movements Less arm swing when walking Reduced facial expression, less blinking Identify by rapid alternating movements during examination

OTHER FINDINGS • • • Facial and scalp seborrhea Myerson’s sign Drooling Hypophonia, micrographia Gait: shuffling, less arm swing, flexed, trouble starting and stopping • Cognitive decline • Normal: strength, DTR, Babinski

DIFFERENTIAL DIAGNOSIS • Depression – facial expression, activity level • Drug-induced – onset usually symmetric • Essential tremor – possibly FH+ • Shy-Drager – parkinsonism + autonomic insufficiency + other signs • PSP • Lewy Body Dementia – parkinsonism, fluctuating cognition, psychosis

TREATMENT • Successful levodopa trial makes diagnosis more likely • Drug aim: restore DA/ACh balance in striatum • No drugs convincingly slow progression • Wait to start drugs until bothersome symptoms or functional impairments

DRUG TREATMENT • Important to individualize • Each patient’s tolerance for side effects? • When is need for mobility greatest?

DRUG TREATMENT • Amantadine – for mild symptoms, risk of confusion and mood problems in elders • Anticholinergics – Benztropine, trihexyphenidyl – Confusion… – Agitation and restlessness… – Urinary retention…

LEVODOPA • Converted by body to DA • Most effective drug • Combined with carbidopa to inhibit breakdown outside the brain (less nausea, hypotension, arrhythmias) • Sinemet (25/100) start one tid, increase gradually as needed • Controlled-release can reduce fluctuations

LEVODOPA, cont’d • • Amino acids compete for absorption Take on empty stomach, or soda crackers Last meal of day has most protein Contraindications: psychosis, narrowangle glaucoma, MAO-A inhibitors • Doesn’t help: autonomic dysfunction, postural instability, dementia, speaking and swallowing

DOPAMINE AGONISTS • Fewer dyskinesias than levodopa • Approved as monotherapy, or as adjunct to levodopa • Adjunctive therapy reduce levodopa fewer dyskinesias, motor fluctuations • Many adverse effects; patients with cognitive impairment may tolerate levodopa better

LEVODOPA VS. DA AGONIST • DA agonist – Perhaps worse motor performance – But less risk of motor complications – Greater odds of adverse drug effects

DA AGONISTS, cont’d • Newer: pramipexole and ropinirole • Older (ergot): bromocriptine and pergolide • Slow dose titration to minimize adverse effects • Fatigue, sleepiness, nausea, dyskinesias, confusion, edema, orthostatic changes, dizziness, flushing and diaphoresis

COMT INHIBITORS • Inhibit Catechol O-Methyl Transferase • Reduce breakdown of levodopa • Smoother blood levels, reduced response fluctuations • Tolcapone – rare fulminant liver failure, avoid in liver disease, monitor LFTs • Entacapone – LFTs not necessary • Watch for diarrhea; reduce Sinemet dose 1/3

SURGICAL TREATMENTS • Ablation (eg, pallidotomy) or DBS • IDEAL CANDIDATE: cognitively intact, responds to dopaminergic drugs but progressive motor symptoms, can withstand procedure • Neurologist evaluation

OTHER TREATMENTS • Physical Therapy – gait training, strength exercises, assistive devices • Improves mood, strength, flexibility, mobility • Front-wheel walkers typically best • Occupational Therapy – techniques and devices for eating, bathing, etc. • Speech Therapy – speaking, swallowing

GEROPSYCHIATRIC COMPLICATIONS IN PD • Psychosis usually due to drug adverse effect – Try reduce dopaminergic dose – Quetiapine, olanzapine, risperidone may help – Clozapine most effective, risk of agranulocytosis • Dementia – Late development, up to ~30% – If earlier, consider Lewy Body Dementia • Depression – in up to ~40%

GASTROINTESTINAL COMPLICATIONS • Dysphagia – Primarily oropharyngeal – Cause of drooling – Choking, coughing, aspiration – Treat: speech therapy

GI COMPLICATIONS, cont’d • Constipation – Slowed colonic transport – Abundant fluids with high-fiber diet – Stool softeners, senna or sorbitol – Avoid anticholinergic medications – Periodic enemas, disimpaction may be needed

Post-test question one Consider the case of a 78 -year-old man with advanced Parkinson's disease who consults you for problems with worsening dyskinesias and excessive drooling. On physical examination you find he has rigidity in both upper extremities, more pronounced on the right, and he also has a pronounced pill-rolling tremor in his right hand. He shows very little spontaneous movement, and his face is expressionless, with rare blinking. On sternal nudge he steps back three steps and almost falls. Which of the following is NOT considered a cardinal feature of his parkinson? s disease? A. Rigidity B. Dyskinesias C. Tremor D. Bradykinesia E. Postural instability

Correct Answer: Dyskinesias Feedback: The answer is (b) Dyskinesias. The other four are part of the cardinal tetrad of Parkinson's disease, which can be remembered using the "TRAP" mnemonic: T for tremor, R for rigidity, A for akinesia or bradykinesia, and P for postural instability. Let's move on to a second question about this patient

Post-test question 2 The best way to treat excessive drooling in a patient with Parkinson's disease is with an anticholinergic agent such as trihexyphenidyl. A. True B. False

• Correct Answer: False • Feedback: As you probably surmised this is false. The drooling in Parkinson's patients results from improper handling of saliva in the oral cavity, not from excess production. This patient may benefit from referral to a speech pathologist. Use of an anticholinergic agent may precipitate confusion, urinary retention, visual complaints, or constipation. End