title: Effects of drink volume and glucose load on gastric emptying and postprandial blood pressure in healthy older subjects.
abstract: Postprandial hypotension (PPH) occurs frequently in the elderly; the magnitude of the fall in blood pressure (BP) is related to the rate of glucose entry into the duodenum during intraduodenal glucose infusion and spontaneous gastric emptying (GE). It is unclear if glucose concentration affects the hypotensive response. Gastric distension may attenuate PPH; therefore, meal volume could influence the BP response. We aimed to determine the effects of 1) drink volume, 2) glucose concentration, and 3) glucose content on the BP and heart rate (HR) responses to oral glucose. Ten subjects (73.9 +/- 1.2 yr) had measurements of BP, GE, and blood glucose on 4 days after 1) 25 g glucose in 200 ml (12.5%), 2) 75 g glucose in 200 ml (37.5%), 3) 25 g glucose in 600 ml (4%), and 4) 75 g glucose in 600 ml (12.5%). GE, BP, HR, and blood glucose were measured for 180 min. After all drinks, duodenal glucose loads were similar in the first 60 min. Regardless of concentration, 600-ml (but not 200-ml) drinks initially increased BP, and in the first 30 min, systolic BP correlated (P < 0.01) with volume in both the proximal and total stomach. At the same concentration (12.5%), systolic BP fell more (P = 0.02) at the smaller volume; at the same volumes, there were no effects of concentration on BP. There was no difference in the glycemic response to drinks of identical glucose content. We conclude that 1) ingestion of glucose at a higher volume attenuates and 2) under constant duodenal load, glucose concentration (4-37%) does not affect the fall in BP.
authors.affiliation: Department of Medicine, University of Adelaide, Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000, Australia. karen.jones@adelaide.edu.au
authors.forename: Karen L
authors.initials: KL
authors.lastname: Jones
authors.forename: Deirdre
authors.initials: D
authors.lastname: O'Donovan
authors.forename: Antonietta
authors.initials: A
authors.lastname: Russo
authors.forename: James H
authors.initials: JH
authors.lastname: Meyer
authors.forename: Julie E
authors.initials: JE
authors.lastname: Stevens
authors.forename: Yong
authors.initials: Y
authors.lastname: Lei
authors.forename: Jennifer
authors.initials: J
authors.lastname: Keogh
authors.forename: Anne
authors.initials: A
authors.lastname: Tonkin
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D001786:Blood Glucose / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D004326:Drinking / Q000502:physiology*; D004386:Duodenum / Q000502:physiology; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects / Q000502:physiology*; D005947:Glucose / Q000008:administration & dosage*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007022:Hypotension / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control*; D008297:Male; D019518:Postprandial Period / Q000502:physiology
chemical_list: D001786:Blood Glucose; D005947:Glucose