Orthostatic Hypotension in Patients with Parkinson's Disease Pathophysiology and Management

Orthostatic hypotension is common in elderly patients, and is now considered to be an important prognostic factor for cognitive decline and mortality. In patients with Parkinson’s disease, the prevalence of symptomatic orthostatic hypotension may be as high as 20%. Two factors could explain this high prevalence. First, dopaminergic drugs may induce or worsen orthostatic hypotension. Secondly, Parkinson’s disease is a cause of primary autonomic failure with an involvement of the peripheral autonomic system as shown by the ubiquitous distribution of Lewy bodies and reduced iobenguane [metaiodobenzylguanidine (MIBG)] cardiac uptake. These pathological and pharmacological characteristics clearly differentiate autonomic failure of Parkinson’s disease from multiple system atrophy. If autonomic abnormalities appear to be present from the first stage of the disease, early onset (within the first year) of symptomatic orthostatic hypotension in the course of parkinsonism can be considered as an exclusion criteria for idiopathic Parkinson’s disease.