Assessment of the effeCt of lIfestyle iNtervention plus water-soluble ciNnAMon extract On loweriNg blood glucose in pre-diabetics, a randomized, double-blind, multicenter, placebo controlled trial: study protocol for a randomized controlled trial

How much is the lack of retention evidence costing trial teams in Ireland and the UK?

BACKGROUND

Evidence to support the use of many retention strategies in clinical trials is lacking. Despite this, trial teams still need to have some form of retention strategy in their trials to try and avoid high attrition rates. This study aimed to estimate how much this lack of retention evidence might be costing trials in Ireland and the UK.

METHODS

We selected the top ten most routinely used retention strategies by Clinical Trial Units in the UK and made assumptions as to how each of these strategies was most likely to be implemented and the costs involved in doing this. We applied our costing model to a hypothetical trial scenario in both Ireland and the UK as well as to three published trial protocols. We developed the costing model and calculated the costs in Microsoft Excel.

RESULTS

Retention strategies were often poorly specified, meaning we had to make assumptions about implementation and in some cases about the strategy itself. Based on our assumptions, some retention strategies can be extremely expensive; some of the costliest strategies included "data collection scheduled with routine care" (€900-€32,503.25), "a timeline of participant visits for sites"-with integrated participant reminder (€304.74-€14,803.70), and "routine site visits by CTU staff" and "investigator meetings face to face", both costing (€777.67-€14,753.48). Others such as "telephone reminders for questionnaire response" (€34.58-€568.62), "a timeline of participant visits for sites"-site reminder alone (€79.18-€112.23), and "targeted recruitment of sites/GPs" (€30-€1620) were less costly compared to the other strategies.

DISCUSSION

The resources invested in the use of some retention strategies may outweigh known or imagined benefits on retention. Where benefits are currently unknown, evaluation should be a priority.

CONCLUSION

More evaluation of the effectiveness and cost of trial retention strategies is needed to avoid widespread use of strategies that are both expensive and ineffective.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

Efficacy and safety of cinnamon in type 2 diabetes mellitus and pre-diabetes patients: A meta-analysis and meta-regression

INTRODUCTION

Cinnamon has been used as a dietary component and in the management of diabetes mellitus. This study systematically reviewed and synthesized evidence on the efficacy of cinnamon for the treatment of type 2 diabetes mellitus (T2DM) and pre-diabetes patients.

METHODS

Databases of Web of Sciences, the Cochrane library, PubMed, CINAHL and SCOPUS were searched. Stata version 13 (College Station, Texas 77845 USA) and RevMan var. 5.3 software were used for meta-analysis. Heterogeneity was assessed using Chi-square and I² tests.

RESULTS

Sixteen randomized controlled studies were included in the meta-analysis. Cinnamon significantly reduced fasting blood glucose (FBG) and homeostatic model assessment for insulin resistance (HOMA-IR) level compared to placebo with weighted mean difference (WMD) of -0.545 (95% CI: -0.910, -0.18) mmol/L, I² = 83.6% and -0.714(-1.388, -0.04), I² = 84.4% respectively. There was no significant change in weighted mean difference of glycosylated hemoglobin A1C (HbA1c) % and lipid profiles (mmol/L). Meta-regression did not show any factor significantly affecting the treatment response.

CONCLUSION

Cinnamon reduced FBG and HOMA-IR, level in T2DM and pre-diabetes patients compared to placebo. High heterogeneity observed among included studies warrants further clinical trials after standardization of cinnamon formulation.

Effect of water-soluble cinnamon extract on electrocardiographic parameters: An analysis of the CiNNaMON trial

OBJECTIVE

To ensure that cinnamon extract does not cause electrocardiographic (ECG) effects in patients with prediabetes.

DESIGN

A subgroup analysis was carried out on data from 103 prediabetic patients participating in the "Effect of Lifestyle Intervention Plus Water-Soluble Cinnamon Extract on Lowering Blood Glucose in Prediabetics" trial. The trial was a randomized, double-blind, placebo-controlled trial comparing cinnamon extract versus placebo in prediabetic adults who committed to participate in a standard-of-care, aggressive lifestyle therapy program.

SETTING

Family Medicine Residency, Mike O'Callaghan Military Medical Center; Family Medicine Residency, David Grant Medical Center, Travis AFB; Wilford Hall Ambulatory Surgical Center, Family Medicine Residency; Eglin AFB, Family Medicine residency; Offutt AFB, Family Medicine Residency.

MAIN OUTCOME MEASURES

QTc interval, QT interval, PR interval, QRS duration and heart rate from ECGs at baseline, 3 months, and 6 months.

RESULTS

Analysis of the ECGs showed no time-matched intra-group differences in any of the ECG parameters (QTc interval, QT interval, PR interval, QRS duration and heart rate; all p-values >0.05).

CONCLUSIONS

Use of cinnamon extract in prediabetic patients does not affect electrocardiographic measures.