Objective: Functional health literacy (FHL) plays a dynamic role in diabetes care, yet research on its implications is erratic in Bangladesh. The aim of this study was to ascertain the level of FHL among patients with type 2 diabetes (T2D) in Dhaka and its correlation with their glycemic level, lifestyle, sleep quality, and sociodemographic characteristics.

Methods: A total of 401 patients with T2D were included by simple random sampling method in this cross-sectional study from three diabetes centers in Dhaka. A Bengali adaptation of the S-TOFHLA (Short Test of Functional Health Literacy) and a semi-structured questionnaire was used to collect data on FHL and other study information. Bivariate analysis, multi-nominal regression, Pearson's χ2 test, and Cramér's V coefficient was used to assess the correlations between variables, with a significance threshold of p < .05.

Key results: Among the 401 participants, 59% were female and 34.9% lived in rural areas; among whom only 27.3% had adequate FHL. Sex, occupation, education, income, physical activity regularity, diabetes treatment regimen, family history, current fasting blood sugar (FBS), 3-month average FBS, 3-month average 2-hour after breakfast blood glucose, and hemoglobin A1c showed significant associations (p < .0001) with the level of FHL. Higher education level significantly increased the odds for adequate FHL (adjusted odds ratios (AOR) = 5.70 to 78.81). Adequate FHL was significantly associated with higher sleep metrics (AOR = 5.67 and 9.17). Longer sleep duration and higher quality sleep increased the likelihood of having adequate FHL (AOR = 9.17 and 5.67, respectively; p < .05) and higher glucose levels were linked to reduced FHL odds (AOR <1).

Conclusions: Higher FHL was associated with better diabetes management. FHL interventions should be evaluated to determine if increasing a patient's health literacy will improve their diabetes management.