Postural hypotension is one of the common non-motor symptoms in Parkinson’s patients and can also be caused or aggravated by medication. In the face of postural hypotension, common antihypertensive drugs are not effective, so how should it be treated?
Neurogenic postural hypotension is common in Parkinson’s patients and is defined as a decrease in systolic blood pressure of ≥ 20 mmHg and diastolic blood pressure of ≥ 10 mmHg within 3 minutes of moving from a prone to an upright position (minimum change > 60°).
Management of postural hypotension is important, and treatment requires first removing the medical cause (e.g., use of antihypertensive medications) and considering nonpharmacologic interventions, with a small number of patients requiring pharmacologic treatment.
Non-pharmacological treatment
Non-pharmacologic interventions for postural hypotension include two main areas: increasing water and salt intake and the use of compression stockings.
1. Conservative treatment of postural hypotension
Treatment is based on the recommended dose of clinical studies increasing salt intake 6-10 g/day increasing water intake 1.5-2.0 L/day compression compression stockings over knee length: 40 mmHg; to thigh length: 30 mmHg; lower limb full length: 20-60 mmHg; abdominal compression: 20-40 mmHg
2.Increase water and salt intake
Increasing water and salt intake can increase blood volume and help maintain upright blood pressure; the recommended daily water and salt intake is 1.5C2.0 L/day and 6-10 g respectively; salt can be supplemented by food or by adjuvant medication; salt intake must be closely monitored as it may lead to cardiovascular complications and increased mortality.
3. Compression stockings
The principle of compression therapy is to reduce the venous volume of the lower extremities, promote venous return and cardiac output, and its efficacy is moderate; four types of compression stockings are available: knee-length, thigh-length, full-length leg, and abdominal compression; compliance with compression stocking therapy is poor, and full-length compression stockings are uncomfortable and difficult to put on and take off; patients prefer compression stockings that go to the ankle joint; for patients with poor compliance, they need to be given Other treatments.
Drug therapy
Most patients require a combination of pharmacologic and non-pharmacologic therapy. Medications can rapidly alter blood pressure levels and need to be carefully monitored for adverse effects, especially in supine hypertension.
1. Fludrocortisone
A systemic steroid that increases circulating catecholamine sensitivity; when treatment with increased water and salt intake is ineffective, fludrocortisone is one of the effective ways to increase plasma volume; the effect is slow, but it can simultaneously increase blood pressure in the supine position, reduce postural symptoms, and increase the patient’s standing time in the upright position; as a first-line drug, the recommended dose is 0.1-0.2 mg/day, which can be taken continuously for 5 days. The recommended dose is 0.1-0.2 mg/day for 5 days; high doses may lead to hypokalemia and prone hypertension; contraindicated in patients with congestive heart failure or chronic renal failure.
2. Midodrine
A peripheral α1-adrenergic agonist that constricts both veins and arteries; takes effect 1 hour after administration; usually given in the morning or morning to avoid evening prone hypertension; recommended dose up to 10 mg tid; maintains effect for 4 hours after each dose; dose-dependent increase in standing systolic blood pressure and significant improvement in postural symptoms; can cause prone hypertension, but It can cause prone hypertension, but its adverse effects can be minimized if taken immediately before upright activity and avoiding bedtime; currently, midodrine is one of two FDA-approved antihypertensive drugs.
3. Droxidopa
A synthetic precursor drug that is converted to norepinephrine by the widespread enzyme dopa decarboxylase; reduces the fall in blood pressure with postural changes and improves postural symptoms; approved by the FDA with a recommended dose of 100 mg tid; efficacy is not significantly affected when used with low-dose dopa decarboxylase inhibitors (25 mg/100 mg levodopa).
4. pyridostigmine
A cholinesterase inhibitor that enhances cholinergic neurotransmission in the autonomic pathway; does not cause the development of proneural hypertension, and clinical studies have shown moderate efficacy; adverse effects include frequent abdominal tightness, nausea, and vomiting, which limit its clinical use; it may also reduce constipation in PD patients.
5. Domperidone
A peripheral dopamine D2 receptor antagonist used to treat acute postural hypotension induced by dopamine agonist therapy; a double-blind cross-sectional study showed that 10 mg tid domperidone was more effective than fludrocortisone; contraindicated in patients with cardiac disease because it increases the risk of QT interval prolongation syndrome.
6. Yohimbine
An α2 adrenergic receptor antagonist that acts by activating the central sympathetic response and promoting the release of norepinephrine; increases blood pressure in sitting and standing positions, with more pronounced increases in sitting blood pressure, and improves dizziness; may be used in combination with a norepinephrine transporter inhibitor to increase its antihypertensive effect.
Summary and recommendations
1. Treatment of postural hypotension in patients with Parkinson’s disease is clinically beneficial, as it may help improve motor and cognitive function and improve quality of life.
2. The management of postural hypotension first requires a reduction in the use of antihypertensive medications, which may be followed by consideration of increased water and salt intake and the use of compression compression stockings.
3. If combination drug therapy is required, the choice should be made according to the severity of the patient’s symptoms and adverse effects.