Individuals with coexisting chronic diseases, named complex chronic disease, are among the costliest and most challenging patients to treat, representing a growing challenge for healthcare. Recommending effective treatments including nutrition interventions, relies on standardised outcome reporting from Randomised Controlled Trials (RCTs) to enable data synthesis. This review sought to determine how the scope and consistency of outcomes reported by RCTs investigating nutrition interventions for the management of complex chronic disease compared to what is recommended by Core Outcome Sets (COS) for individual disease states. Peer-reviewed RCTs published between January 2010 and July 2020 were systematically sourced from PubMed, CINAHL and Embase, and COS were sourced from the International Consortium for Health Outcomes Measurements (ICHOM) and the Core Outcome Measures in Effectiveness Trials (COMET) database. Forty-five RCTs (43 studies) and 7 COS were identified. Cochrane’s Risk of Bias 2.0 tool was used to assess RCT quality. Outcomes were extracted from both RCTs and COS, and organised using COMET Taxonomy Core Areas (Death, Physiological/Clinical, Life Impact, Resource Use, Adverse Events). Sixty-six outcomes and 439 outcome measures were reported by RCTs. RCTs demonstrated extensive outcome heterogeneity, with only five outcomes (5/66, 8%) being reported with relative consistency (cited by =50% of publications). Furthermore, the scope of outcomes reported by studies was limited with a notable paucity of patient reported outcomes. Poor agreement (25%) was observed between the outcomes reported in RCTs and those recommended by COS. This review urges greater uptake of existing COS and development of a COS for complex chronic disease to be considered, so that evidence can be better synthesised regarding effective nutrition interventions.Contributors
Savita A Sandhu 1*, Chloe Angel 1*, Katrina L Campbell 2, Ingrid J Hickman 3,4, Helen L MacLaughlin 1,5
1 School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT); firstname.lastname@example.org; email@example.com.
2 Healthcare Excellence and Innovation, Metro North Hospital and Health Service, Brisbane, Australia; firstname.lastname@example.org
3 Department of Nutrition and Dietetics, Princess Alexandra Hospital, Brisbane Australia; email@example.com
4 Faculty of Medicine, University of Queensland, Brisbane, Australia
5 Royal Brisbane and Women’s Hospital, Brisbane, Australia; firstname.lastname@example.org
* equal co-authorship
- Systematic review of outcomes measured in trials
- Systematic review
Peer-reviewed RCTs published between January 2010 and July 2020 were systematically sourced from PubMed, CINAHL and Embase, and COS were sourced from the International Consortium for Health Outcomes Measurements (ICHOM) and the Core Outcome Measures in Effectiveness Trials (COMET) database. RCTs were included if the population met the criteria for complex chronic disease (two or more lifestyle-related diseases [chronic kidney disease, type 2 diabetes, cardiovascular disease, liver disease, metabolic syndrome] or one lifestyle disease and a feature of metabolic syndrome [obesity, hypertension, dyslipidaemia, insulin resistance]. Additionally, RCT interventions had to be predominantly nutrition-related (defined as intentional change to individual nutritional intake for the purpose of disease management.
Outcomes from these were extracted and classified according to the COMET Taxonomy Core Areas and Domains. The scope and consistency of outcomes reported by RCTs was determined, and compared to the outcomes COS for relevant individual disease states currently request.
Cochrane’s Risk of Bias 2.0 tool was used to assess RCT quality.