Implementation of a very low calorie diet to reverse type 2 diabetes in Barbados: a feasibility study

Investigators:

Nigel Unwin, Andre Greenidge, Clive Landis, Chronic Disease Research Centre, Tropical Medicine Research Institute, Bridgetown, Barbados

Other investigators:

Karen Bynoe, Charles Taylor and Maddy Murphy, Faculty of Medical Sciences, Cave Hill Campus; Roy Taylor, University of Newcastle, UK

Funding Obtained:

115,000 USD from Virgin Unite

Start Date:

January 2015

End Date:

February 2016

Rationale:

Type 2 diabetes is highly prevalent in Barbados and responsible for a high burden of complications and premature mortality. Recently it has been shown that a short (2 or 3 month) very low calorie diet, followed by weight maintenance, is able to reverse type 2 diabetes and restore normal insulin and glucose metabolism, so long as undertaken within six years following diagnosis. This aim of this study is to determine the acceptability and transferability of a very low calorie diet plus structured long‐term support in Barbados.

Methods:

Each participant is being provided with a very low calorie liquid diet over an 8‐week period, supplemented by high fibre low carbohydrate vegetables. This is being followed by a 6‐ month period during which individuals will be given on‐going dietetic and medical advice. Success is being evaluated using standard meal tests with assessment of insulin secretion and insulin sensitivity as well as usual clinical parameters. Qualitative work is being undertaken to help identify from the points of view of the study participants barriers and facilitators to successful completion of the intervention. The target sample size for this feasibility study is 25.

Main Results:

Twenty five participants have been recruited, and 13 have completed the 8 week liquid diet phase and at the time of writing are in transition back to a normal solid diet. The other 12 participants are in the third week of the liquid diet. So far there have been no drop outs and no adverse events. Indeed, all participants have lost weight and have improved glucose control, despite stopping all glucose lowering medication at the start of the study. Blood pressure control has also improved, and has led to stopping blood pressure lowering medication in several participants.

Expected impact:

This study has generated a huge amount of interest within Barbados, from Government Ministers to the general public. It is hoped that the feasibility study will provide the basis for a larger study within Barbados and other parts of the Caribbean – as described below.

Next Steps / Future Plans:

The findings from this study will be used to design a well powered, pragmatic trial designed to determine the effectiveness and cost‐effectiveness of this intervention when delivered through routine health care services in Barbados and other parts of the Caribbean. Ideally this will be designed as a cluster randomised controlled trial.