Idiopathic reactive hypoglycaemia – Prevalence and effect of fibre on glucose excursions

Abstract

Background. Idiopathic reactive hypoglycaemia (IRH) is a condition characterized by aggravated postprandial glucose excursions in otherwise healthy individuals. We investigated its prevalence and the impact of fibre diet supplementation. Methods. First, IRH prevalence was assessed in 362 subjects without a diagnosis of abnormal glucose metabolism through an oral glucose tolerance test (OGTT). IRH was defined by 1 h- or 2 h-glucose ≤3.9 mmol/L or 1 h- or 2 h-glucose < fasting glucose. Second, in a cross-over trial we evaluated effects of 2 weeks with, and without, 20 g fibre (fructose- oligosaccharides) diet supplementation in subjects with IRH. At the end of each 2-week cycle we analysed fasting biomarker levels and conducted a 4 h-OGTT. Results. IRH was found in 12.4% and a normal glucose tolerance in 56.4% of the participants. The IRH group was characterized by higher fasting (5.3 vs. 5.2 mmol/L, p < 0.05) but lower 2 h- (4.4 vs. 6.5 mmol/L, p < 0.01) glucose levels, whereas age (68 ± 10 vs. 70 ± 9 years) and BMI (24.7 ± 3.3 vs 25.0 ± 3.5 kg/m²) were similar. The 2-week fibre diet-supplementation (n = 12, age 56 ± 8 years, 6 females, BMI 25.0 ± 2.9 kg/m²) improved both the reactive glucose pattern during the 4 h-OGTT (significantly increased late-onset glucose nadirs and reduced the frequency of glucose ≤3.9 mmol/L [21 to 11, p = 0.04]) and reduced fasting plasma glucose (5.4 ± 0.6 to 5.1 ± 0.5 [p < 0.05]) and total cholesterol (5.3 ± 1.1 to 4.9 ± 1.1 mmol/L [p < 0.04]). Conclusions. A reactive glucose pattern following intake of a high glycaemic load is relatively prevalent and this phenomenon could be modulated by dietary fibre supplementation.

Key Words::

• Endocrinology
• hypoglycemia
• glucose
• dietary fibre

Acknowledgements

We thank Abbot Norway for generously providing glucose meters to the cross-over study (Freestyle Lite, Abbott), the Research Foundation and Medical Department of Vestre Viken, Asker and Baerum Hospital for funding the study, Elsa Orvik for technical assistance and Tehri Kahra for providing the diet plan.

Declaration of interest: OEJ is an associated post-doctoral researcher at Vestre Viken, Asker and Baerum Hospital, but is currently a Senior Research Physician of Boehringer-Ingelheim.