Secondary parkinsonism

1) Disease Description (Causes and Symptoms)

• Definition: Secondary parkinsonism refers collectively to cases in which parkinsonian symptoms are present but the cause is not idiopathic Parkinson disease. Depending on the cause, it is classified as drug-induced parkinsonism, normal-pressure hydrocephalus (NPH), vascular parkinsonism, and others.
• Major causes
  • Drug-induced: Occurs when dopamine function is inhibited by antipsychotics (dopamine D2 blockers), some gastrointestinal motility-enhancing agents (e.g., levosulpiride), and other drugs.
  • Normal-pressure hydrocephalus: Brain compression due to ventricular enlargement → gait disturbance, urinary dysfunction, and cognitive decline.
  • Vascular: Damage to motor circuits caused by microischemia/infarction of the basal ganglia or subcortical white matter.
• Pathophysiology: Although it differs by cause, abnormalities in dopaminergic function or connectivity within the basal ganglia–motor circuits commonly lead to bradykinesia, tremor, rigidity, and gait disturbance.
• Major symptoms: Slowness of movement (slow sequential movements), tremor, muscle rigidity, bradykinesia, gait disturbance (short-stepped gait, freezing of gait), and postural instability. Depending on the cause, urinary dysfunction, cognitive decline, and speech difficulties may also occur.

2) Treatment Methods (Standard Treatment · Medications · Procedures/Surgery · Lifestyle Management and Precautions)

• Prioritize the diagnostic approach: Identify the cause (review of medications, brain CT/MRI, and, in some cases, lumbar puncture and specialized brain imaging tests such as DAT-SPECT) → determine treatment according to the cause.
• Pharmacological treatment
  • Drug-induced: Stop or replace the causative medication (if possible, switch to a non-dopamine-blocking drug). If symptoms are severe, dopamine agonists (such as levodopa) may be administered temporarily for a short period, but the response varies.
  • Vascular: Typically shows a minimal response to levodopa. Medications for symptom relief are limited.
• Surgery/Procedures
  • Normal-pressure hydrocephalus (NPH): After observing temporary improvement through a diagnostic lumbar puncture, long-term improvement may be expected with ventriculoperitoneal shunt surgery.
  • Functional surgery for severe symptoms (e.g., deep brain stimulation) may be considered depending on the cause and patient selection, but indications are limited in secondary causes.
• Non-pharmacological treatment
  • Physical therapy/exercise therapy: Gait rehabilitation, balance training, and muscle strengthening.
  • Occupational therapy: Maintaining and improving activities of daily living (ADL).
  • Speech therapy: When voice or swallowing difficulties are present.
• Prevention and management of complications
  • Fall prevention, management of urinary dysfunction and cognitive decline, and evaluation and treatment of depression and sleep disorders.
• Precautions (including self-care)
  • Avoid using dopamine-blocking medications (such as antipsychotics), and when necessary, consult the prescribing physician about alternative medications.
  • Actively manage vascular risk factors (hypertension, diabetes, hyperlipidemia, and smoking).
  • Record worsening or improvement of symptoms when medications are changed and report it to the doctor.
  • If hydrocephalus is suspected, neuroimaging and lumbar puncture are necessary.

3) Checkpoints Before an Outpatient Visit (Including Items to Bring and Sample Questions)

• Items and information to bring
  • A list of all medications currently being taken (including prescription drugs, over-the-counter drugs, herbal medicines, and supplements), as well as recent medication history (start date, dosage, and timing of changes)
  • Copies of recent test results (brain CT/MRI, blood tests, etc.), if possible
  • The onset and course of symptoms (when they began, whether they appeared suddenly or progressed gradually), and the main problems (gait, tremor, cognition, urination, etc.)
  • A history of falls and videos showing activity limitations, if possible
• Symptom checklist to write down in advance for the outpatient visit
  • Tremor (when and in what situations), slowed movement, gait changes, freezing, urinary and cognitive changes, and the relationship to the time medications were started
• Possible tests/referrals
  • Neuroimaging (MRI/CT), lumbar puncture (if hydrocephalus is suspected), DAT-SPECT (if necessary), neurological examination, and cognitive assessment

4) Examples of General Questions to Ask the Doctor

• "How do you distinguish whether my symptoms are secondary parkinsonism or idiopathic Parkinson disease?"
• "Could any of the medications I am taking be causing this? Which medications should I stop or replace?"
• "How much can my symptoms improve with treatment, and what is the prognosis?"
• "What measures should I take at home to reduce the risk of falls?"
• "What additional tests are needed, such as brain imaging or a lumbar puncture?"

5) Examples of Disease-Specific Questions

• If drug-induced parkinsonism is suspected:
  • "Could the OOO medication I am taking cause parkinsonian symptoms? If I stop taking it, when might my symptoms improve?"
• If normal-pressure hydrocephalus (NPH) is suspected:
  • "If the brain imaging or lumbar puncture results suggest hydrocephalus, which symptoms—gait, cognition, or urinary incontinence—are most likely to improve with shunt surgery? What are the risks of the surgery?"

Additional guidance: Because treatment and prognosis vary greatly depending on the cause, please bring a list of your medications and brain imaging results whenever possible and consult a neurologist.