Mamaw's Diagnosis

Orthostatic hypotension can be caused by several different disorders that affect the entire body (systemic disorders), the central nervous system (CNS, consisting of the brain and spinal cord), and the autonomic nervous system (peripheral autonomic neuropathy) or as a result of taking certain medications that are commonly prescribed by clinicians. Systemic causes can include dehydration, prolonged immobility or an endocrine disorder called adrenal insufficiency. Diseases of the CNS that can cause orthostatic hypotension include MSA (multiple systems atrophy), Parkinson's disease, multiple strokes, brain stem lesions, myelopathy.

Medications that can cause orthostatic hypotension include Tricyclic antidepressants, antipsychotics,monoamine oxidase inhibitors, antihypertensives, diuretics, vasodilators, Levodopa, beta-blockers (heart medications), and blood pressure medications that inhibit a chemical called angiotensin(angiotensin-converting-enzyme inhibitors). Disorders that cause peripheral autonomic neuropathy include diabetes mellitus, amyloidosis, tabes dorsalis (late manifestations of syphilis infection), alcoholism, nutritional deficiency, pure autonomic failure or paraneoplastic syndromes.

The most common symptoms of orthostatic hypotension include weakness, lightheadedness, cognitive impairment, blurred vision, vertigo and tremulousness. Other symptoms that have been reported include headache, paracervical pain, lower back pain, syncope, palpitations, angina pectoris, unsteadiness, falling, and calf claudication.

Diagnosis

It is important that the clinician take numerous blood pressure measurements on different occasions, since blood pressure can vary (i.e. postural hypotension, another disorder causing hypotension, is often worse in the morning when rising from bed). A detailed history and physical examination is important. The clinician should focus medical evaluation on autonomic symptoms and diseases. There are bedside tests that can determine autonomic (baroreceptor) response (i.e. Valsalva maneuver). Measurements of a chemical in blood called norepinephrine while lying down and for five to 10 minutes after standing, can produce some useful information concerning deficits in autonomic nervous system functioning. Additionally, levels of another chemical in blood (called vasopressin) during upright tilting, can help to distinguish if the cause is due to ANS failure or from as a result of MSA. Pure ANS failure is characterized by increased vasopressin levels, whereas patients with MSA have no appreciable increase of vasopressin levels during head tilting.

Treatment team

Primary care practitioner (internist); or in complicated cases (severe orthostatic hypotension) aneurologist is consulted.

Treatment

Nonsymptomatic orthostatic hypotension is a threat for falls or syncope and could be treated by preventive measures that include avoiding warm environments and increasing one's blood pressure bysquatting, stooping forward, or crossing one's leg. Additionally, persons affected with the nonsymptomatic variation should increase salt intake, sleep in the head-up position, wear waist-high compression stockings and withdraw from drugs that are known to cause orthostatic hypotension as a side effect. Treatment for symptomatic orthostatic hypotension is important since it is a manifestation of a new illness or as a result of medications. Intervention can initially be nonpharmacologic (preventive measures and adjustments) or pharmacologic therapy. Nonpharmacologic intervention includes a review of medications, since elderly patients may be taking either OTC or prescribed drugs that can induce orthostatic hypotension. Persons affected should rise slowly to the erect position after a long period of sitting or lying down. They should avoid excess heat environments (i.e. in shower or central heating systems), coughing, straining or heavy lifting since these events can precipitateepisodes of orthostatic hypotension. There are certain measures that can redirect blood to increase blood pressure and reduce symptoms associated with orthostatic hypotension. These measures include squatting, sitting down, crossing legs, and stooping forward.