Impairment of the postural venoarteriolar reflex in aged individuals.
The venoarteriolar vasoconstriction reflex plays a major role in the prevention of leg oedema in the upright position in man. We studied the venoarteriolar vasoconstriction reflex with laser Doppler flowmetry in young (21 subjects, age 17-27) and very old (20 subjects, age 75-100) healthy volunteers. In the group of young volunteers, after lowering of the lower extremity 50 cm below the heart level, cutaneous blood flux decreased to 16.6% of the baseline, whereas in the group of old persons the venoarteriolar reflex was impaired and the flux decreased only to 29.2%. The difference between the two groups was statistically significant (p < 0.001). These results may explain the increased prevalence of postural oedema in old people.
Gniadecka
M
M
Department of Dermatology, Bispebjerg Hospital, Copenhagen, Denmark.
Gniadecki
R
R
Serup
J
J
Søndergaard
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004487:Edema / Q000209:etiology; D005260:Female; D006801:Humans; D007866:Leg / Q000098:blood supply; D008297:Male; D011187:Posture / Q000502:physiology*; D012018:Reflex / Q000502:physiology*; D014666:Vasomotor System / Q000502:physiology*