Measuring orthostatic hypotension with the Finometer device: is a blood pressure drop of one heartbeat clinically relevant?

OBJECTIVE

The role of orthostatic hypotension in falls in older people is generally accepted. Because of the high degree of intra- and interobserver variability in conventional measurements of orthostatic hypotension, application of continuous measurement systems has been proposed. The clinical relevance of a blood pressure drop lasting one heartbeat, however, is unknown. We therefore investigated which time average of continuous-finger-blood-pressure measurement (Finometer) showed the best association between orthostatic hypotension and falls. This was also compared with conventional sphygmomanometer measurements.

METHODS

In 217 geriatric outpatients supine and standing (finger) blood pressure to diagnose orthostatic hypotension was monitored with Finometry (beat-to-beat and 1, 5, 10, 15, 20 and 30 s averages) and sphygmomanometry. History of fall incidents (previous year) was registered.

RESULTS

The best association (C=0.22, P=0.003) with falls history was found for the 5-s average of Finometry, whereas falls and orthostatic hypotension assessed by sphygmomanometry did not correlate. The odds ratio of a fall according to orthostatic hypotension using the 5-s average was 2.54 (95% CI: 1.37 to 4.71).

CONCLUSIONS

Orthostatic hypotension and falls are correlated when using Finometry, with the best association found when using 5-s averages. As the etiology of falls is often multifactorial, orthostatic hypotension and falls are poorly correlated, irrespective of the method or time average that is applied.