What is the best course of action for an older patient exhibiting slow and jerky movements, hand tremors, and stress?

Evaluation and Management of Older Patients with Slow, Jerky Movements, Hand Tremors, and Stress

The priority is to systematically distinguish between Parkinson's disease, functional movement disorder, and secondary causes through focused neurological examination, with particular attention to bradykinesia, tremor characteristics, and metabolic abnormalities that are common and treatable in older adults.

Initial Clinical Assessment

The neurological examination must focus on specific features that differentiate organic from functional movement disorders:

• Assess for bradykinesia, which is the essential diagnostic feature required alongside resting tremor to diagnose Parkinson's disease 1
• Test for rigidity by passively moving the patient's limbs while instructing complete relaxation, noting resistance throughout the full range of motion and any cogwheel phenomenon 1
• Use activation maneuvers (having the patient open and close the opposite hand) while testing for rigidity, as this brings out subtle rigidity that might otherwise be missed 1
• Characterize the tremor pattern: resting tremor suggests Parkinson's disease, while variable frequency, amplitude, and entrainability suggest functional tremor 2
• Evaluate for "jerky movements": irregular, involuntary movements in random sequence suggest chorea, which in older adults may be associated with systemic lupus erythematosus or antiphospholipid syndrome 3

Screen for Red Flags and Secondary Causes

Critical features that suggest alternative diagnoses or treatable causes:

• Check for vertical gaze palsy, asymmetric rigidity with alien hand phenomenon, early severe autonomic dysfunction, or cerebellar signs, which suggest atypical parkinsonian syndromes rather than Parkinson's disease 1
• Assess stress and psychological context: functional tremors typically worsen with attention and improve with distraction, and may develop following injury, illness, or psychological distress 2
• Evaluate medication history: neuroleptics can cause drug-induced parkinsonism or akathisia, antidepressants are associated with periodic limb movements, and various medications can enhance physiologic tremor 3

Essential Laboratory Evaluation

Metabolic abnormalities are common in older adults and can induce or worsen movement disorders:

• Measure serum calcium and parathyroid hormone (PTH), as hypocalcemia can induce or worsen tremors and movement disorders 3, 1
• Check magnesium levels, as hypomagnesemia contributes to tremor 1
• Assess thyroid-stimulating hormone (TSH) to exclude thyroid dysfunction 1
• Obtain serum ferritin if restless legs syndrome is suspected; values less than 50 ng/mL warrant iron supplementation 3
• Check vitamin B12, folate, and vitamin D levels, as deficiencies impact neurological symptoms 1

Diagnostic Imaging Strategy

• Order MRI brain without contrast as the initial imaging study to rule out structural causes, focal lesions, or vascular disease, though it is often normal in early Parkinson's disease 1
• Consider I-123 ioflupane SPECT/CT (DaTscan) if the clinical presentation is unclear or differentiation from essential tremor or functional tremor is needed; a normal scan essentially excludes parkinsonian syndromes 1
• Do not order DaTscan for disease monitoring—it is only useful at initial diagnosis, not to evaluate progression 1

Management Based on Diagnosis

If Parkinson's Disease is Confirmed:

• Initiate carbidopa-levodopa starting with one tablet of 25 mg/100 mg three times daily, providing 75 mg of carbidopa per day 4
• Titrate dosage by one tablet every day or every other day as necessary, up to eight tablets daily 4
• Monitor closely during dose adjustment, as both therapeutic and adverse responses occur more rapidly with carbidopa-levodopa than with levodopa alone 4
• Watch for involuntary movements (dyskinesias), which may require dosage reduction; blepharospasm may be an early sign of excess dosage 4
• Use the Unified Parkinson's Disease Rating Scale (UPDRS) or MDS-UPDRS to objectively track disease severity and treatment response 1

If Functional Movement Disorder is Suspected:

• Provide clear, empathetic explanation of the diagnosis that acknowledges the involuntary nature of symptoms 2
• Implement rhythm modification techniques: superimpose alternative voluntary rhythms on top of the existing tremor and gradually slow all movement to complete rest 3, 2
• Use entrainment strategies: for unilateral tremor, use the unaffected limb to dictate a new rhythm (tapping/opening and closing the hand) to entrain the tremor to stillness 3
• Incorporate music to dictate a rhythm for the patient to follow 3
• Address unhelpful pre-jerk cognitions and movement such as signs of anxiety, frustration, or breath-holding 3
• Teach relaxation techniques: diaphragmatic breathing, progressive muscular relaxation, and sensory grounding strategies 3
• Avoid pharmacotherapy for functional tremor, as there is no evidence supporting benefit 2
• Minimize adaptive equipment use, as aids are generally unhelpful and may reinforce illness behavior 3, 2

If Chorea is Present:

• Consider systemic lupus erythematosus and check antiphospholipid antibodies, especially if other systemic symptoms are present 3
• Initiate symptomatic therapy with dopamine antagonists (haloperidol), which is usually effective 3
• Add glucocorticoids in combination with immunosuppressive agents (azathioprine, cyclophosphamide) if lupus activity is present 3
• Consider antiplatelet or anticoagulation therapy in antiphospholipid-positive patients 3

Critical Pitfalls to Avoid

• Do not assume the diagnosis without specialist confirmation, as correctly diagnosing parkinsonian syndromes on clinical features alone is challenging 1
• Do not attribute worsening tremor to disease progression without first correcting metabolic abnormalities (especially hypocalcemia and hypomagnesemia) and optimizing medication timing and dosing 1
• Do not confuse spasticity with rigidity during examination 1
• Do not dismiss functional symptoms or fail to acknowledge their involuntary nature, as this damages therapeutic alliance 2
• Do not provide excessive adaptive equipment for functional disorders, as this may prevent future improvement by interrupting normal automatic movement patterns 3
• Do not abruptly discontinue carbidopa-levodopa if Parkinson's disease is diagnosed, as sporadic cases of hyperpyrexia and confusion have been associated with dose reductions and withdrawal 4

Stress Management Considerations

Given the patient's stress:

• Address stress as both a potential trigger and consequence of movement disorders, particularly in functional disorders where psychological distress may precede symptom onset 2
• Implement stress reduction techniques including cognitive behavioral therapy, which may benefit patients with functional neurological symptoms 2
• Evaluate for concurrent psychiatric conditions that may require treatment, as stress and psychiatric symptoms commonly coexist with movement disorders 3