"Subclinical" orthostatic hypotension is associated with dizziness in elderly patients with Parkinson disease.

OBJECTIVE

To investigate risk factors associated with subjective complaints of dizziness in 12 elderly patients with Parkinson disease (PD), in whom no obvious cause for this symptom could be found.

DESIGN

A case-controlled study, with patients prospectively recruited in a nonblinded fashion.

SETTING

Patients were seen by one physician at a neurology outpatient clinic between August 1993 and August 1994.

SUBJECTS

Thirty-six patients, all over age 65 years and all with PD; 12 complained of dizziness; 24 did not.

INTERVENTIONS

Patients and controls were screened for blood pressure changes, postural instability, motor severity, multiple sensory deficits, drug use, cardiovascular disease, and diabetes mellitus.

MAIN OUTCOME MEASURES

An orthostatic decrease of systolic BP > 15 mmHg (odds ratio = 6.5; 95% confidence interval = 1.22 - 34.52; chi 2mh = 6.7; p < .01) and an orthostatic decrease of diastolic BP > 5mmHg (odds ratio = 11; 95% confidence interval = 3.15 - 38.39; chi 2mh = 7.14; p < .01) were significant risk factors for complaints of dizziness.

RESULTS

The only significant risk factors linked with dizziness were orthostatic decreases in systolic (15 mmHg) and diastolic (5 mmHg) blood pressure.

CONCLUSIONS

An orthostatic decrease in blood pressure is associated with unexplained feelings of dizziness in elderly PD patients.