Introduction
Screening for nOH
Question | Screening questions* |
---|---|
1 | Have you fainted/blacked out recently? |
2 | Do you feel dizzy or lightheaded upon standing? |
3 | Do you have vision disturbances when standing? |
4 | Do you have difficulty breathing when standing? |
5 | Do you have leg buckling or leg weakness when standing? |
6 | Do you ever experience neck pain or aching when standing? |
7 | Do the above symptoms improve or disappear when you sit or lay down? |
8 | Are the above symptoms worse in the morning or after meals? |
9 | Have you experienced a fall recently? |
10 | Are there any other symptoms you commonly experience when you stand up or within 3–5 min of standing and get better when you sit or lay down? |
Diagnosis of nOH in individuals who screen positive for OH
Diagnostic tests for nOH
Blood pressure testing
A practical stepwise approach to orthostatic blood pressure and heart rate testing
In-clinic monitoring of blood pressure and heart rate
At-home monitoring of blood pressure and heart rate
Medication review
Exclude other causes of OH/nOH
Test | Function in OH/nOH differential diagnosis |
---|---|
Electrocardiogram | To evaluate cardiac electrical activity |
Complete blood count (CBC) | To evaluate for anemia, or infection that could contribute to non-neurogenic OH |
Basic metabolic panel (sodium, potassium, chloride, bicarbonate, blood urea nitrogen, creatinine and fasting glucose) | To look for hypo/hypernatremia, hypo/hyperkalemia, acid–base disorders, blood volume depletion (BUN:Cr ratio >20 mg/dL:1 mg/dL), renal dysfunction or diabetes |
TSH | To evaluate for thyroid dysfunction |
B12 level, Methylmalonic acid | To look for evidence of B12 deficiency |
Secondary Laboratory Tests (Considered for Use in Select Patients) | Function in OH/nOH differential diagnosis |
---|---|
Albumin | To identify poor nutrition or chronic illness |
Liver enzyme testing, albumin | To evaluate for hepatic dysfunction in patients with weight loss and constitutional symptoms |
Neurological antibody studies (paraneoplastic panel) | To identify autoantibodies; rarely indicated; only in patients with subacute onset of nOH in the presence of other neurological or constitutional symptoms suggesting an autoimmune or paraneoplastic syndrome. A pure autonomic failure syndrome should be tested for anti-ganglionic acetylcholine receptor antibodies |
Serum and urine protein electrophoresis | To identify a monoclonal gammopathy; only in patients with features of peripheral neuropath |
Specialty testing
If the diagnosis is OH and not nOH
Class of medications | Common examples |
---|---|
Dopaminergic agents | Levodopa, dopamine agonists |
Antidepressants (particularly tricyclic agents)a
| Amitriptyline, nortriptyline, imipramine, desipramine |
Anticholinergics | Atropine, glycopyrrolate, hyoscyamine |
Anti-hypertensive agents | |
Preload reducers
| |
Diureticsa
| Furosemide, torsemide, acetazolamide, hydrochlorothiazide, spironolactone |
Nitratesa
| Nitroprusside, isosorbide dinitrate, nitroglycerin |
Phosphodiesterase E5 inhibitors | Sildenafil, vardenafil, tadalafil |
Vasodilators
| |
Alpha-1 adrenergic antagonistsa
| Alfuzosin, doxazosin, prazosin, terazosin, tamsulosin (used primarily for benign prostatic hyperplasia) |
Dihydropyridine calcium channel blockers | Amlodipine, nifedipine, nicardipine |
Other direct vasodilators | Hydralazine, minoxidil |
Negative inotropic/chronotropic agents
| |
Beta-adrenergic blockers | Propranolol, metoprolol, atenolol, bisoprolol, nebivolol (also vasodilator), carvedilol (also alpha-1 antagonist), labetalol (also alpha-1 antagonist) |
Non-dihydropyridine calcium channel blockers | Verapamil, diltiazem |
Central sympatholytic agents
| |
Centrally acting alpha-2 agonists | Clonidine |
False neurotransmitters | Alpha-methyldopa |
Renin–angiotensin system (RAS) antagonists
| |
Angiotensin converting enzyme (ACE) inhibitors | Captopril, enalapril, perindopril, |
Angiotensin receptor type II blockers (ARB) | Losartan, telmisartan, candesartan |
Grading of nOH after diagnosis
Grade | Attributes |
---|---|
1 | Infrequent symptoms/unrestricted standing time AND mild OH [20-30 mmHg drop in SBP during supine-to-standing test] |
2 | ≥5 min standing time (but not unrestricted) AND [> 30 mmHg drop in SBP OR moderate impact ADL] |
3 | <5 min standing time AND [> 30 mmHg drop in SBP OR severe impact on ADL] |
4 | <1 min standing time AND [> 30 mmHg drop in SBP OR incapacitated] |
Post-prandial hypotension
Treating nOH
Treating nOH—step 1: review and adjust current medications
Treating nOH—step 2: non-pharmacological measures
Blood volume repletion
Salt intake
Physical conditioning
Avoid increased core body temperature
Head-up position while sleeping
Compression garments
Diet
Anemia and vitamin/mineral deficiencies in the diet
Treating nOH—step 3: initial pharmacologic treatment
FDA-approved drugs for the treatment of OH/nOH
Midodrine
Droxidopa
Off-label use of FDA-approved drugs for the treatment of orthostatic hypotension
Fludrocortisone
Pyridostigmine
Recommendations for initiating nOH treatment
Recommendations for changing nOH treatment
Treating nOH—step 4: combination pharmacotherapy
Assessing nOH treatment success
Referring the nOH patient
Supine hypertension
Defining supine hypertension in patients with nOH
Measuring supine hypertension in patients with nOH
Supine hypertension associated with nOH
Treatment options* | Mechanism of action | Typical dose |
---|---|---|
Captopril | ACE inhibitor | 25 mg qhs |
Clonidinea
| Central α-2 agonist | 0.2 mg with evening meal |
Hydralazine | Peripheral smooth muscle relaxant | 10–25 mg qhs |
Losartan | Angiotensin II receptor antagonist | 50 mg qhs |
Nitroglycerine patch | Vasodilator | 0.1 mg/h patch qhs (remove patch in AM) |