Guar gum reduces postprandial hypotension in older people.
OBJECTIVE
To determine whether slowing of gastric emptying and glucose absorption with guar gum would reduce the fall in blood pressure after an oral glucose load in older subjects.


METHODS
A randomized, experimental, cross-over study.


METHODS
Department of Nuclear Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia.


METHODS
Ten healthy subjects, age 67 to 78.


METHODS
Simultaneous measurements of gastric emptying, blood pressure, blood glucose, serum insulin, and oral glucose absorption (3-O-methyl-D-glucose [3-OMG]) on two occasions after ingestion of 300 mL water containing 50 g glucose and 30 mL lemon juice, 3 g 3-OMG labeled with 99mTc-sulphur colloid; with or without 9 g guar gum. Blood pressure and gastric emptying were monitored for 180 minutes.


RESULTS
The magnitude of the falls in systolic (P = .02), diastolic (P < .05), and mean arterial (P = .05) blood pressure were less, and gastric emptying slower (P < .05), after guar. Blood glucose, insulin, and 3-OMG concentrations were reduced (P < .001 for all) by guar. 3-OMG concentrations were inversely related to the intragastric retention of glucose (r = -0.72, P = .02) and blood pressure was inversely related to 3-OMG (r = -0.64, P < .05) after the drink without guar. The blood glucose concentration was related to 3-OMG (r > 0.64, P < .05).


CONCLUSIONS
Guar gum reduces the magnitude of the fall in blood pressure after oral glucose. Slowing of gastric emptying and glucose absorption may represent a novel approach to the treatment of postprandial hypotension.
Jones
K L
KL
Department of Medicine, Royal Adelaide Hospital, University of Adelaide, South Australia, Australia.
MacIntosh
C
C
Su
Y C
YC
Wells
F
F
Chapman
I M
IM
Tonkin
A
A
Horowitz
M
M
D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001786:Blood Glucose / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D018592:Cross-Over Studies; D003971:Diastole / Q000187:drug effects; D016903:Drug Monitoring; D005260:Female; D005685:Galactans / Q000494:pharmacology / Q000627:therapeutic use*; D005746:Gastric Emptying / Q000187:drug effects; D006801:Humans; D007022:Hypotension / Q000209:etiology* / Q000378:metabolism / Q000517:prevention & control*; D007328:Insulin / Q000097:blood; D007408:Intestinal Absorption / Q000187:drug effects; D016014:Linear Models; D008297:Male; D008351:Mannans / Q000494:pharmacology / Q000627:therapeutic use*; D053149:Plant Gums; D019518:Postprandial Period / Q000187:drug effects*; D013599:Systole / Q000187:drug effects; D013997:Time Factors
D001786:Blood Glucose; D005685:Galactans; D007328:Insulin; D008351:Mannans; D053149:Plant Gums; C007894:guar gum