Autonomic stress and balance--the impact of age and diabetes.
BACKGROUND
Balance is impaired in the elderly and people with diabetes. However, the effect of attempted balance on the autonomic nervous system has not been investigated.


METHODS
Ten control subjects, 10 subjects with type 2 diabetes (age range, 21-75 years), and 10 older subjects age-matched to the subjects with diabetes were examined to determine the effect of diabetes and age on balance and the associated autonomic stress. Subjects were asked to stand on a balance platform for 1-min periods under four conditions: (1) quiet standing, (2) quiet standing with eyes closed, (3) quiet standing eyes closed with the platform allowed to move side to side over a central pivot that allows the edge of the platform to rotate 4 inches up and down, and (4) the same platform with eyes closed. Blood pressure, electrocardiogram, and sway were recorded.


RESULTS
Balance was worst in the subjects with diabetes, while the cardiovascular stress, as assessed by both heart rate and blood pressure, was greatest in the older group of subjects. But subjects with diabetes, while having a greater blood pressure response to the stress induced by balance, showed a poor heart rate response, probably due to diabetes-induced autonomic damage.


CONCLUSIONS
Autonomic damage in the subjects with diabetes masked much of the stress of the inability to optimize balance in this population.
Petrofsky
Jerrold Scott
JS
Department of Physical Therapy, School of Allied Health Professions, Loma Linda University, Loma Linda, California 92350, USA. jpetrofsky@llu.edu
Focil
Nicholas
N
Prowse
Michele
M
Kim
Yumi
Y
Berk
Lee
L
Bains
Gurinder
G
Lee
Scott
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D004856:Postural Balance / Q000502:physiology*; D013312:Stress, Physiological