Health literacy is known to influence adherence to treatment recommendations and self-management in chronic patients. However, studies demonstrating the impact of health literacy on treatment adherence generally measure the patient's health literacy level in a general way, without distinguishing between specific health literacy skills. The present study aimed to investigate the impact of four specific dimensions of health literacy (understanding, evaluating, accessing, applying) on self-management behavior and well-being of diabetic patients.

Method: A sample of 107 diabetic patients consulting at a Belgian hospital completed the Health Litteracy Survey (HLS_EU_47), the Diabetes Self-Management Questionnaire (DSMQ_16), and two direct questions measuring self-reported adherence to the doctor’s treatment recommendations and perceived difficulty of self-management. The predictive value of health literacy and of the four sub-dimensions of the health literacy on diabetes self-management, treatment adherence and perceived difficulty in self-management, in addition to demographic and medical predictors (patient’s age at onset and at diagnosis, complications, comorbidities, having received a training in disease self-management) was tested using stepwise multiple regression analyses.

Results: Having received self-management education and the presence of complications significantly predicted treatment adherence and self-management. This impact increased slightly when scores on the 4 sub-dimensions of health literacy were added as predictors. Of the four subdimension of health literacy, evaluating health information adds most to the prediction of treatment adherence and self-management.

Conclusion: While treatment adherence and self-management of diabetes are most strongly influenced by patient education, complications of the disease, and age at diagnosis, health literacy adds to the prediction. Among the subdimensions of health literacy, the dimension evaluating information has the greatest impact on adherence to the doctors’ recommendations and self-management.