Amazon Amandaba—Sociodemographic Factors, Health Literacy, Biochemical Parameters and Self-Care as Predictors in Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study

Background: Health literacy (HL) and its domains (functional, critical, and communicative) appear to be related to self-care adherence in people with type 2 diabetes mellitus (DM2). This study aimed to verify if sociodemographic variables are predictors of HL, if HL and the sociodemographic factors affect biochemical parameters together, and if HL domains are predictors of self-care in DM2. Methods: We used the baseline assessment data from 199 participants ≥ 30 years in the project, “Amandaba na Amazônia: Culture Circles as a Strategy to Encourage Self-care for DM in Primary Health Care,” which took place in November and December 2021. Results: In the HL predictor analysis, women (p = 0.024) and higher education (p = 0.005) were predictors of better functional HL. The predictors of biochemical parameters were: glycated hemoglobin control with low critical HL (p = 0.008); total cholesterol control with female sex (p = 0.004), and low critical HL (p = 0.024); low-density lipoprotein control with female sex (p = 0.027), and low critical HL (p = 0.007); high-density lipoprotein control with female sex (p = 0.001); triglyceride control with low Functional HL (p = 0.039); high levels of microalbuminuria with female sex (p = 0.014). A low critical HL was a predictor of a lower specific diet (p = 0.002) and a low total HL of low medication care (p = 0.027) in analyses of HL domains as predictors of self-care. Conclusion: Sociodemographic factors can be used to predict HL, and HL can predict biochemical parameters and self-care.