Low carbohydrate diets and cardiovascular health: an example of a rapid response with high quality reviews to inform public health promotion

Article type
Authors
Naude CE1, Schoonees A1, Young T1, Senekal M2, Volmink J1, Garner P3
1Centre for Evidence-Based Health Care, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
2Division of Human Nutrition, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, South Africa
3Effective Health Care Research Consortium, International Health Group, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
Abstract
Background: Low carbohydrate diets for weight management and cardiovascular-related benefits have generated controversy between advocates, the media and the health profession in South Africa over the last two years. The Heart and Stroke Foundation of South Africa approached the Centre for Evidence-based Health Care to provide evidence to inform their response to the ongoing debates.

Objectives: (1) To provide a reliable summary of the effects of low carbohydrate diets on cardiovascular health for a public health client; (2) To road-test a feasible, robust and timely approach for completing a systematic review in response to a public health concern.

Methods: We established a review team that wrote the protocol and a multidisciplinary technical group that provided advice. We firstly conducted an overview of systematic reviews. When clear answers were not identified, we carried out a rapid systematic review of randomised controlled trials using Cochrane methods, addressing the gaps identified in the overview.

Results: The overview revealed 38 existing systematic reviews of mostly low and moderate quality from AMSTAR scores. All had a variety of problems relating to inclusion criteria and comparisons that made interpretation and generalisability difficult. This phase helped us design a protocol that more closely aligned the advocated diets to the various trials, with clear delineation of inclusion criteria and comparisons. We carried out a rigorous review of 19 RCTs against the protocol approved by the technical group, which is potentially rapidly adaptable as a Cochrane Review.

Conclusions: We completed a review against an approved protocol on a complex topic that fed straight into public health promotion in less than a year. This illustrates the power of listening to stakeholders, the value of timely information, and the ability to deliver a rigorous review rapidly. Cochrane Groups should have the capacity to complete such reviews rapidly with active, capable teams.