Evaluation of orthostatic hypotension: relationship of a new self-report instrument to laboratory-based measures.
OBJECTIVE
To compare measured autonomic deficits (composite autonomic severity score [CASS]) with a brief self-report scale we developed to measure severity of symptoms of orthostatic hypotension.


METHODS
Patients were recruited in 2 phases: from August to October 2002 and in April 2004. All patients underwent full evaluation in the autonomic laboratory, from which a CASS of autonomic deficits was derived. Patients also completed the 5-item self-report Orthostatic Grading Scale, which inquires about symptoms of orthostatic intolerance due to orthostatic hypotension (eg, severity, frequency, and interference with daily activities).


RESULTS
Of 145 patients, 97 (67%) had orthostatic hypotension. The 5-item scale demonstrated strong internal consistency (coefficient alpha=.91). Patients with orthostatic hypotension had significantly higher scores on each questionnaire item and CASS subscores than those without orthostatic hypotension. The scale items correlated significantly with each of the CASS subscores, maximally with the CASS adrenergic subscore.


CONCLUSIONS
Orthostatic hypotension is not the only cause of reduced orthostatic tolerance, and some patients may have orthostatic hypotension but be asymptomatic. Results of this study indicate that this 5-item questionnaire is a reliable and valid measure of the severity of symptoms of orthostatic hypotension and that it can supplement laboratory-based measures to provide a rapid, more complete clinical assessment. This questionnaire would also be useful as a brief screening device for orthostatic intolerance to aid physicians in identifying patients who may have orthostatic hypotension.
Schrezenmaier
Christine
C
Autonomic Disorders Center, Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minn 55905, USA.
Gehrking
Jade A
JA
Hines
Stacy M
SM
Low
Phillip A
PA
Benrud-Larson
Lisa M
LM
Sandroni
Paola
P
D000203:Activities of Daily Living; D000368:Aged; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires