Blood pressure associates with standing balance in elderly outpatients

Abstract

Objectives: Assessment of the association of blood pressure measurements in supine and standing position after a postural change, as a proxy for blood pressure regulation, with standing balance in a clinically relevant cohort of elderly, is of special interest as blood pressure may be important to identify patients at risk of having impaired standing balance in routine geriatric assessment.

Materials and methods: In a cross-sectional cohort study, 197 community-dwelling elderly referred to a geriatric outpatient clinic of a middle-sized teaching hospital were included. Blood pressure was measured intermittently (n = 197) and continuously (subsample, n = 58) before and after a controlled postural change from supine to standing position. The ability to maintain standing balance was assessed during ten seconds of side-by-side, semi-tandem and tandem stance, with both eyes open and eyes closed. Self-reported impaired standing balance and history of falls were recorded by questionnaires. Logistic regression analyses were used to examine the association between blood pressure and 1) the ability to maintain standing balance; 2) self-reported impaired standing balance; and 3) history of falls, adjusted for age and sex.

Results: Blood pressure decrease after postural change, measured continuously, was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed and with increased self-reported impaired standing balance and falls. Presence of orthostatic hypotension was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed for both intermittent and continuous measurements and with increased self-reported impaired standing balance for continuous measurements.

Conclusion: Continuous blood pressure measurements are of additional value to identify patients at risk of having impaired standing balance and may therefore be useful in routine geriatric care.

Figure 1. Ability to maintain balance in several standing positions with eyes open and eyes closed.

A) all elderly patients (n = 197) and for B) subgroup who underwent additional continuous blood pressure measurements (n = 58).

Figure 2. Percentage of elderly patients able to maintain balance during side-by-side and semi-tandem stance with eyes closed.

Data is given for tertiles of systolic and diastolic blood pressure (BP) decrease, continuously measured, during the time period in seconds after postural change. *P values derived from logistic regression analyses with adjustments for age and sex.

Figure 3. Forest plots of the association between blood pressure and A) reported impaired standing balance and B) history of falls.

Blood pressure measures were determined with continuous measurements in subgroup who underwent additional continuous blood pressure measurements (n = 58). Orthostatic hypotension: 0  =  absent, 1  =  present; defined as a decrease in systolic blood pressure of ≥ 40 mmHg or in diastolic blood pressure of ≥ 20 mmHg during 15 seconds after postural change or a decrease in systolic blood pressure of ≥ 20 mmHg or diastolic blood pressure of ≥ 10 mmHg between 15 and 180 seconds after postural change. Reported impaired balance: 0  =  never or sometimes, 1  =  regularly or always. History of falls: 0  =  no falls, 1  =  falls. Results are presented in odds ratios per 10 mmHg blood pressure decrease and 95% confidence intervals with adjustments for age and sex. No overlap with 1.0 indicates a significant difference.