A randomised controlled trial of a probiotic and a prebiotic examining metabolic and mental health outcomes in adults with pre-diabetes

Abstract

AimsTo evaluate the effect of the probioticLactobacillus rhamnosusHN001 and/or cereal enriched with oat-derived beta-glucan (OBG) on metabolic and mental health outcomes when administered to adults with pre-diabetes.Design2×2 factorial design randomised, parallel-groups placebo-controlled; double-blinded for probiotic, single-blinded for cereals.ParticipantsCommunity-dwelling adults aged 18–80 years with pre-diabetes: glycated haemoglobin (HbA1c) 41–49 mmol/mol.InterventionsCapsules containingLactobacillus rhamnosus(HN001) (6×109colony-forming units/day), or placebo capsules; and cereal containing 4 g/day OBG or calorie-matched control cereal, taken daily, for 6 months. Study groups were: (A) HN001 capsules+OBG cereal; (B) HN001 capsules+control cereal; (C) placebo capsules+OBG cereal and (D) placebo capsules+control cereal.Outcome measuresPrimary outcome: HbA1cat 6 months. Secondary outcomes: fasting plasma glucose, fasting insulin, homeostatic model assessment of insulin resistance, fasting lipids, blood pressure, body weight, waist circumference, body mass index and mental well-being.Results153 participants were randomised. There was complete HbA1coutcome data available for 129 participants. At 6 months the mean (SD) HbA1cwas 45.9 (4.4) mmol/mol, n=66 for HN001, and 46.7 (4.3) mmol/mol, n=63 for placebo capsules; 46.5 (4.0) mmol/mol, n=67 for OBG and 46.0 (4.6) mmol/mol n=62 for control cereal. The estimated difference between HN001-placebo capsules was −0.83, 95% CI −1.93 to 0.27 mmol/mol, p=0.63, and between OBG-control cereals −0.17, 95% CI −1.28 to 0.94 mmol/mol, p=0.76. There was no significant interaction between treatments p=0.79. There were no differences between groups or significant interactions between treatments for any of the secondary outcomes.ConclusionsThis study found no evidence of clinical benefit from the supplementation with either HN001 and/or cereal containing 4 g OBG on HbA1cand all secondary outcomes relevant to adults with pre-diabetes.Trial registration numberAustralian New Zealand Clincial Trials Registry number ACTRN12617000990325

Effects of a diverse prebiotic fibre supplement on HbA1c, insulin sensitivity, and inflammatory biomarkers in pre-diabetes: a randomised placebo-controlled clinical trial

“…Consistent with these results, a recent study in pre-diabetes found that improvements in glycaemic outcomes in response to inulin supplementation could be predicted by better baseline glycaemic status (26). This has been supported in previous work, showing that supplementation with inulin improved outcomes in a pre-diabetes population with lower baseline HbA1c values (5.4 ± 0.1%, mean ± SD) ( 27) while another study using 4g oat beta-glucan found no effects on HbA1c or secondary outcomes in a pre-diabetes population with higher baseline values (HbA1c 6.4 ± 0.4%, mean ± SD) (28). These studies are consistent with our results, showing that patients who are earlier in the pre-diabetic disease pathway may be more likely to respond metabolically to prebiotic fibre interventions.…”

Probiotics intervention in preventing conversion of impaired glucose tolerance to diabetes: The PPDP follow-on study

“…The results of randomized controlled studies on pregnant women with gestational diabetes or obesity showed that probiotic intervention had no effect on glycemic control, but might improve lipid metabolism (18,19).In another study of prediabetes adolescents, it was not observed that oral probiotics could improve FBG and HbA1c after 4 months (20). Similarly, in a 24-week probiotic intervention study on adults with prediabetes, the goodness of glycosylated hemoglobin was not observed (21). Our studies are consistent with the conclusion of these studies that probiotics have a limited therapeutic effect on metabolic diseases.…”

Effects of synbiotic supplementation on the health-related quality of life in women with polycystic ovary syndrome. A randomized, triple-blind, placebo-controlled trial

“…Unlike the two mentioned studies, in a 6-month study based on both probiotic and prebiotic administration in pre-diabetics, no signi cant difference found in SF-36 and depression, anxiety and stress scale (DASS-21) scores. However, there was no betterment in any of the metabolic or anthropometric outcomes, either (37). Positive impact of probiotic/synbiotic on the HRQoL was evident in healthy people (38) and in patients with IBS (39), systemic sclerosis (40), Cirrhosis (41) and minor digestive symptoms (42).…”