The Effect of a Low-Glycemic Index Diet on Postprandial Hypotension in Individuals With Chronic Spinal Cord Injury: Results From a Pilot Study.

Background: One in two individuals with spinal cord injury (SCI) experiences postprandial hypotension (PPH), a decline (>20 mm Hg) in systolic blood pressure (SBP) within 2 hours after eating. Consuming meals with a low glycemic index (GI) could prevent or lessen PPH.

Objectives: To determine the effect of a low-GI diet on PPH and postprandial glucose and insulin in individuals with chronic SCI (>1 year postinjury).

Methods: Eleven participants (6 males, 5 females; age 43 ± 11 years) with chronic SCI (C4-C7, 7; T4-T12, 4) took part in a randomized crossover study (low GI vs. high GI). On each occasion, BP, glucose, and insulin were measured in the fasted state and for 2 hours after consuming a breakfast meal (60% carbohydrate, 28% fat, 12% protein) in laboratory-controlled conditions. Participants wore an ambulatory BP monitor and continuous glucose monitor for 3 days at home, and consumed study meals that were macronutrient-matched across conditions.

Results: The maximum decrease in systolic blood pressure (SBP) following the laboratory-controlled breakfast meals tended to be lower in the low-GI (14 ± 12 mm Hg) compared to the high-GI (24 ± 25 mm Hg) diet (d = 0.52, P = .056). Serum glucose (P < .01) and insulin (P = .026) concentrations were lower at 30 minutes in the low-GI diet. In the home setting, peak glucose concentrations were lower after lunch (P = .011) and dinner (P < .01) in the low-GI diet.

Conclusion: A low-GI meal may be an effective solution to reduce the magnitude of PPH and peak glucose concentrations in individuals with chronic SCI.