TY - JOUR

T1 - The clinical effects of a carbohydrate-reduced high-protein diet on glycaemic variability in metformin-treated patients with type 2 diabetes mellitus: A randomised controlled study

AU - Thomsen, Mads Norvin

AU - Skytte, Mads Juul

AU - Astrup, Arne

AU - Deacon, Carolyn F

AU - Holst, Jens Juul

AU - Madsbad, Sten

AU - Krarup, Thure

AU - Haugaard, Steen Bendix

AU - Samkani, Amirsalar

N1 - CURIS 2020 NEXS 271

PY - 2020

Y1 - 2020

N2 - Background & aims: High glycaemic variability (GV) is associated with late complications in type 2 diabetes (T2D). We hypothesised that a carbohydrate-reduced high-protein (CRHP) diet would reduce GV acutely in patients with T2D compared with a conventional diabetes (CD) diet. Methods: In this controlled, randomised crossover study, 16 patients with metformin-treated T2D (median (IQR) age: 64.0 (58.8–68.0) years; HbA1c: 47 (43–57) mmol/mol; duration of T2D: 5.5 (2.8–10.3) years) were assigned to an energy-matched CRHP diet and CD diet (31E%/54E% carbohydrate, 29E%/16E% protein and 40E%/30E% fat, respectively) for two separate 48-h intervention periods. Interstitial continuous glucose monitoring (CGM) was performed to assess accepted measures of glycaemic variability, i.e. standard deviation (SD) around the sensor glucose level; coefficient of variation in percent (CV); mean amplitude of glucose excursions (MAGE); continuous overlapping net glycaemic action (CONGA1, CONGA4) of observations 1 and 4 h apart; and mean absolute glucose (MAG) change. Results: All indices of glycaemic variability (mean ± SD) were significantly reduced during CRHP diet compared with CD diet; including SD (1.0 ± 0.3 (CRHP) vs 1.6 ± 0.5 mmol/L (CD)), CV (12.3 ± 3.8 vs 19.3 ± 5.5%), MAGE (2.3 ± 0.9 vs 4.2 ± 1.3 mmol/L), CONGA1 (0.8 ± 0.3 vs 1.5 ± 0.4 mmol/L), CONGA4 (1.4 ± 0.5 vs 2.5 ± 0.8 mmol/L), and MAG change (0.9 ± 0.3 vs 1.4 ± 0.4 mmol/L/h) (p < 0.001 for all). Compared with the CD diet, the CRHP diet improved the diurnal glucose profile by reducing 24-h mean sensor glucose (7.7 ± 1.6 vs 8.6 ± 2.0 mmol/L). Conclusions: In T2D patients treated with diet and metformin, two days of iso-energetic replacement of dietary carbohydrates by protein and fat reduced all indices of glycaemic variability by 36%–45% when compared with a conventional diabetes diet. These data may support reduction of carbohydrates as dietary advice for T2D patients. Clinicaltrials.gov identifier: NCT02472951.

AB - Background & aims: High glycaemic variability (GV) is associated with late complications in type 2 diabetes (T2D). We hypothesised that a carbohydrate-reduced high-protein (CRHP) diet would reduce GV acutely in patients with T2D compared with a conventional diabetes (CD) diet. Methods: In this controlled, randomised crossover study, 16 patients with metformin-treated T2D (median (IQR) age: 64.0 (58.8–68.0) years; HbA1c: 47 (43–57) mmol/mol; duration of T2D: 5.5 (2.8–10.3) years) were assigned to an energy-matched CRHP diet and CD diet (31E%/54E% carbohydrate, 29E%/16E% protein and 40E%/30E% fat, respectively) for two separate 48-h intervention periods. Interstitial continuous glucose monitoring (CGM) was performed to assess accepted measures of glycaemic variability, i.e. standard deviation (SD) around the sensor glucose level; coefficient of variation in percent (CV); mean amplitude of glucose excursions (MAGE); continuous overlapping net glycaemic action (CONGA1, CONGA4) of observations 1 and 4 h apart; and mean absolute glucose (MAG) change. Results: All indices of glycaemic variability (mean ± SD) were significantly reduced during CRHP diet compared with CD diet; including SD (1.0 ± 0.3 (CRHP) vs 1.6 ± 0.5 mmol/L (CD)), CV (12.3 ± 3.8 vs 19.3 ± 5.5%), MAGE (2.3 ± 0.9 vs 4.2 ± 1.3 mmol/L), CONGA1 (0.8 ± 0.3 vs 1.5 ± 0.4 mmol/L), CONGA4 (1.4 ± 0.5 vs 2.5 ± 0.8 mmol/L), and MAG change (0.9 ± 0.3 vs 1.4 ± 0.4 mmol/L/h) (p < 0.001 for all). Compared with the CD diet, the CRHP diet improved the diurnal glucose profile by reducing 24-h mean sensor glucose (7.7 ± 1.6 vs 8.6 ± 2.0 mmol/L). Conclusions: In T2D patients treated with diet and metformin, two days of iso-energetic replacement of dietary carbohydrates by protein and fat reduced all indices of glycaemic variability by 36%–45% when compared with a conventional diabetes diet. These data may support reduction of carbohydrates as dietary advice for T2D patients. Clinicaltrials.gov identifier: NCT02472951.

KW - Continuous glucose monitoring

KW - Glycaemic variability

KW - Low-carbohydrate diet

KW - Type 2 diabetes

U2 - 10.1016/j.clnesp.2020.07.002

DO - 10.1016/j.clnesp.2020.07.002

M3 - Journal article

C2 - 32859328

AN - SCOPUS:85088952095

VL - 39

SP - 46

EP - 52

JO - Clinical Nutrition ESPEN

JF - Clinical Nutrition ESPEN

SN - 2405-4577

ER -