Associations of literacy with diabetes indicators in older adults

Literacy, the ability to access, understand and utilise information and concepts from diverse sources in ways that promote good outcomes is key to successful ageing. Domain-specific health and financial literacy are particularly relevant to older adults as they face increasingly complex health and financial demands including those related to chronic conditions like type 2 diabetes. We therefore investigated the associations of literacy, including health and financial literacy, with diabetes indicators (ie, haemoglobin A1c and blood glucose) in a community-based cohort study of ageing.

Participants were 908 non-demented older adults (age ~81 years;75% women) from the Rush Memory and Aging Project. Literacy was measured using questions designed to assess comprehension of health and financial information and concepts and yielded a total score and domain-specific health and financial literacy scores. Non-fasting haemoglobin A1c and blood glucose samples were collected, participants were queried about diabetes status and medications for diabetes were visually inspected and coded. Participants also underwent a cognitive assessment, medical history and depressive symptom screening.

In separate multivariable linear regression models, total (p values <0.03) and health (p values <0.009) literacy were inversely associated with haemoglobin A1c and blood glucose levels after adjusting for age, sex, education, hypertension, global cognitive functioning and depressive symptoms. Financial literacy was inversely associated with haemoglobin A1c levels in adjusted models (p=0.04). Sensitivity analyses conducted among individuals without diabetes revealed similar results.

Lower literacy levels are associated with higher diabetes indicators, particularly haemoglobin A1c which is suggestive of longer-term glycaemic instability.