A clinical, physiology and pharmacology evaluation of orthostatic hypotension in the elderly.

Orthostatic hypotension is very common in the elderly. It increases morbidity and is an independant predictor of all cause mortality. It is defined as a fall in systolic blood pressure greater than 20 mm Hg or a fall in diastolic blood pressure greater than 10 mm Hg within 3 minutes of standing. Symptoms include light headedness, weakness, blurred vision, fatigue and lethargy and falls. Most patients have orthostatic hypotension due to non neurogenic causes. Drugs like antihypertensives and tricyclic antidepressants are very common causes of orthostatic hypotension. Diagnosis is based on the history and a thorough clinical examination. Based on the history and physical examination, further testing of the heart, kidneys and autonomic nervous system may be required in selected patients. Non pharmacological methods like slow position change, increased fluid and sodium intake, compression stockings and elevation of head of the bed are the key to management of orthostatic hypotension. After these methods, pharmacological treatment with fludrocortisone and midodrine should be tried. Other drugs like desmopresin acetate, xamoterol, erythropoetin and ocreotide can be used as second line agents in selected patients.