Disease-related knowledge, health behaviours and clinical outcomes following an educational intervention in patients with diabetes according to their health literacy level: a systematic review

Abstract

Background: The effectiveness of education programs designed to improve disease-related knowledge and change behaviours in people with diabetes has been established. Low health literacy (HL) is considered a barrier to improving health outcomes in people with diabetes. The evidence of the effects of education programs considering HL levels in diabetes has not been previously systematically reviewed. Aim: This systematic review aimed to verify the impact of education on patients' knowledge, health behaviour change and clinical outcomes in patients with diabetes with low and marginal Health Literacy (HL). Methods: A literature search of electronic databases was conducted for published articles from database inception to April 2020. Eligible articles included assessment of HL, disease-related knowledge, health behaviours (physical activity, diet, smoking cessation, medication adherence, self-care), and clinical outcomes (diabetes management based on A1C values, self-efficacy, perceived susceptibility of complications, self-reported medical care, patient activation, and diabetes-related distress) in diabetes patients that receive any type of education intervention. Results: Overall, 8 articles were included, of which 4 (50%) were RCTs. Four studies were considered "fair" quality. The most used screening instrument to assess HL was the Test of Functional Health Literacy in Adults short form (S-TOFHLA; n=5, 62.5%). All studies showed improvement in disease-related knowledge and behaviour after an education program, regardless of HL level. The overall quality of the evidence of the studies was graded as low to very low according to the GRADE scale. Included studies differed substantially in their education programs characteristics, such as mode of delivery and intervention content. Conclusion: Educational interventions can improve knowledge, change behaviour and improve clinical outcomes of diabetic patients with low or marginal health literacy.