Here - American Geriatrics Society

P APER
A BSTRACTS
be amenable to interventions designed to prevent the occurrence,
persistence, or recurrence of this common disorder in older persons.
P29
Falls and Orthostatic Hypotension: Re-examining Limits.
A. Cleinman, 1 M. E. Griswold, 2 E. Simonsick, 3 W. M. Meeks, 1
K. Gregg, 1 L. Ferrucci, 3 B. G. Windham. 1 1. Department of Medicine,
Division of Geriatrics, University of Mississippi Medical Center,
Jackson, MS; 2. Center of Biostatistics and Bioinformatics, University
of Mississippi Medical Center, Jackson, MS; 3. Clinical Research
Branch, NIH - National Institute on Aging, Baltimore, MD.
Supported By: National Institutes of Health, National Institute
on Aging
Background: Guidelines recommend treating orthostatic hypotension
(OH) to reduce risk of falls in older adults. We hypothesized
that low systolic blood pressure (SBP) upon standing and/or decreases
from usual SBP, even without meeting OH criteria, would also
be related to falls risk.
Methods: Baltimore Longitudinal Study of Aging participants (
>65y) with a first visit that evaluated OH and self-report of falls in the
previous 12 months were examined. Participants with >10 visits were
excluded to minimize extended cohort participation bias. OH was defined
using the classical definition of SBP decrease >20mmHg or diastolic
BP decrease > 10mmHg, 3 minutes after standing from a
supine, resting position. Logistic regression was used to examine associations
between falls and BP measures, adjusting for age, sex, race,
education, stroke, diabetes, hypertension, and vision.
Results: Among 412 participants, (aged 65-97, 45% female, 64%
white), 115 (28%) reported falling: 77 had one fall and 38 reported >2
falls. Only 19 participants (4.6%) had formally defined OH. Falls
were more common in those with OH (53% vs 27%, p=0.033). In adjusted
models, falls were significantly associated with OH, OR=3.05
(95% CI: 1.06, 8.78) p=0.038, but not with final standing SBP,
OR=1.01 (0.99, 1.02) p=0.358. Furthermore, each 1mmHg decrease in
SBP upon standing was associated with an additional 6% increase in
risk, OR=1.06 (1.01, 1.10) p=0.008. This is equivalent to 31%, 73%,
and 198% increases in risk for 5, 10, and 20mmHg drops in SBP. The
risk associated with decreases in SBP upon standing did not depend
on the final standing SBP (p=0.74 for interaction).
Conclusions: The risk of falls in this sample depended on decreases
in SBP upon standing rather than the final standing SBP. Although
classically defined OH was associated with falls, increased
risks were seen for any decrease in SBP upon standing, even those
not meeting OH criteria. This suggests that a continuous spectrum of
SBP drops upon standing conveys important information about risk.
Any SBP drop may warrant consideration in falls risk assessments.
P30
Sensory and motor nerve function differentially relate to gait
parameters: the Health ABC Study.
E. S. Hile, 1 J. S. Brach, 1 M. Yang, 1 S. A. Studenski, 1 R. M. Boudreau, 1
P. Caserotti, 2,3 S. Satterfield, 5 A. V. Schwartz, 4 E. Simonsick, 2
L. Ferrucci, 2 T. B. Harris, 2 A. B. Newman, 1 E. S. Strotmeyer. 1 1.
University of Pittsburgh, Pittsburgh, PA; 2. National Institute on
Aging, Baltimore, Bethesda, MD; 3. University of Southern Denmark,
Odense, Denmark; 4. University of California, San Francisco, CA; 5.
University of Tennessee, Memphis, TN.
Supported By: National Institute on Aging (NIA) Contracts N01-
AG-6-2101; N01-AG-6-2103; N01-AG-6-2106; NIA grant R01-
AG028050, and NINR grant R01-NR012459.
Pittsburgh Claude D. Pepper Older Americans Independence
Center (P30 AG024827)
BACKGROUND: Many older adults have subclinical or undiagnosed
peripheral nerve decline. Sensory decline is associated with
gait deviations [reduced speed; increased double support time (DST)
and base of support (BOS)] in diabetic or neuropathic cohorts, but
less is known about age-related decline. Poor sensory and motor
nerve function associate with slower speed in the Health ABC cohort,
but how biomechanical gait parameters explain this is unknown.
We investigated relationships between nerve function and spatial or
temporal gait parameters. METHODS: Of 3075 baseline Health
ABC participants, we included 544 (83.4±2.7 yrs, 52.9% women,
35.5% black) with Year 11 gait parameters [4-m usual walk speed,
BOS, step length, step time, DST, stance and swing time] and nerve
function [sensory:1.4 and 10g monofilament (MF) detection, vibration
threshold (VT); motor: peroneal nerve conduction velocity
(NCV) and amplitude (CMAP)]. Gait parameters were outcomes
modeled with each nerve predictor by multivariate regression adjusted
for age, sex, race, BMI, diabetes, PVD, stroke, physical activity,
smoking and vision. Most gait parameters vary with speed, so final
models were adjusted for speed to assess independence. RESULTS:
Worse sensory and motor nerve function by VT or CMAP (but not
MF or NCV) related to slower speed. Worse VT associated with
longer stance and step times (p