Introduction: Postprandial hypotension (PPH), a fall in systolic blood pressure (SBP) of >20mmHg after a meal, occurs frequently in older people and type 2 diabetes (T2DM). Current management of PPH is suboptimal. The magnitude of the postprandial fall in BP is greater when gastric emptying (GE) is relatively more rapid (1). Intravenous administration of glucagon-like peptide-1 (GLP-1) slows GE and attenuates the postprandial fall in BP and rise in splanchnic blood flow in T2DM (2).
Objectives: We evaluated the effects of the prandial GLP-1RA, lixisenatide (LIXI), on GE and the BP, superior mesenteric artery (SMA) blood flow, and glycaemic responses to a 75g oral glucose load in healthy and T2DM subjects.
Methods: 15 healthy subjects (9M, 6F; age: 67.2 ± 2.3yr) and 15 T2DM patients (9M, 6F; age: 61.9 ± 2.3yr) had measurements of GE, BP, SMA blood flow and plasma glucose for 180min after a radiolabelled 75g glucose drink on 2 separate days. All subjects received LIXI (10mcg sc) or placebo (PLAC) in a randomised, double-blind, crossover fashion 30min before the drink.
Results: LIXI slowed GE (Retention at 120min) (P<0.01) and attenuated the fall in SBP (AUC 0-120min) (P<0.001) compared to PLAC in healthy subjects and T2DM, with no difference between the groups. The maximum rise in SMA flow was attenuated by LIXI in both the healthy subjects and T2DM (P<0.01), but was greater in the healthy subjects than T2DM on both PLAC and LIXI days (P<0.001). Plasma glucose (iAUC 0-120min) was greater in T2DM (P<0.005) than healthy subjects, and reduced by LIXI in both groups (P<0.001).
Conclusions: In health and T2DM, the marked slowing of GE and consequent reduction in glycaemia induced by lixisenatide are associated with attenuation of the rise of SMA flow and fall in SBP. Accordingly, lixisenatide may be useful in the management of PPH.