The impact of health literacy on physical and psychological frailty in cardiovascular outpatients

Background Health literacy (HL) refers to the ability to understand and appropriately utilize health information to maintain and improve health. Patients with low HL may face difficulties in practicing healthy behaviors, potentially accelerating the progression of various types of frailty. This study hypothesized that low HL would be associated with physical, psychological, and social frailty in patients with cardiovascular disease and aimed to investigate this association. Methods A questionnaire survey was conducted among 1,090 outpatients attending a cardiovascular clinic between August 2022 and March 2023 (median age: 74 years; 36% female). In addition to evaluating lifestyle habits, HL was assessed using the Communicative and Critical Health Literacy (CCHL) scale, and participants were divided into two groups based on the median CCHL score: a low HL group and a high HL group. Frailty was evaluated using the Clinical Frailty Scale (CFS) and grip strength for physical frailty, Patient Health Questionnaire-2 (PHQ-2) for depressive symptoms, and Generalized Anxiety Disorder-7 (GAD-7) for anxiety symptoms as measures of psychological frailty. Living alone was used as an indicator of social frailty. Physical and psychological frailty indicators were reassessed after one year. Associations between low HL and each frailty indicator, as well as their progression, were analyzed using logistic regression analysis, adjusting for potential confounders: age, sex, B-type natriuretic peptide, New York Heart Association classification, left ventricular ejection fraction, estimated glomerular filtration rate, Controlling Nutritional Status (CONUT) score, hypertension, diabetes mellitus, smoking history, exercise habits, gardening activities, pet ownership, and vegetable intake. Results Compared to the high HL group, the low HL group exhibited significantly lower rates of exercise and vegetable intake (p < 0.01). No significant associations were observed with grip strength or living alone after adjustment. However, Low HL was significantly associated with higher CFS, PHQ-2, and GAD-7 scores (Table 1). It was also linked to worsening PHQ-2 and GAD-7 scores (Table 2), with consistent associations across age groups. Conclusion Low HL in cardiovascular outpatients is significantly associated with physical and psychological frailty, especially the progression of psychological frailty, regardless of age. These results imply that strengthening HL may play a role in mitigating frailty, especially psychological frailty.