Effect of health literacy and socioeconomic deprivation on outcomes after lower limb surgical revascularisation for chronic limb-threatening ischaemia: the HeaLTHI study

Abstract

Introduction: Research has suggested a relationship between health literacy, socioeconomic status and health-related outcomes. The aim of the study was to study the association between health literacy, socioeconomic status and outcomes following infra-inguinal bypass surgery for chronic limb-threatening ischaemia (CLTI). Methods: Patients with CLTI undergoing lower limb surgical bypass graft operations between January 2016 and December 2018 were included in a cross-sectional observational study. The HLS19-Q12 questionnaire categorised participant’s health literacy as inadequate, problematic, sufficient or excellent. Socioeconomic status was assessed using the Index of Multiple Deprivation (IMD). Primary outcomes were major lower limb amputation (MLLA) and adverse cardiovascular events. Secondary outcomes included length of hospital stay, and early postoperative complications including pneumonia, surgical site and graft infection. Kaplan– Meier survival curves were used to compare health literacy and amputation, and Cox proportional regression analysis was conducted to identify differences in limb loss risk against health literacy and social deprivation levels. Results: The study consisted of 50 patients with an average age of 70±8.7 years. The participants' levels of health literacy were classified as inadequate (28%), problematic (38%), sufficient (24%) or excellent (10%). Approximately 40% of the patients lived in the most deprived areas. While all health literacy groups had similar postoperative outcomes, low health literacy was connected with lower socioeconomic status (r=0.308, p=0.029). IMD (p=0.017, HR 0.502 (95% CI 0.285 to 0.883)) and haemoglobin (p=0.001, HR 0.919 (95% CI 0.872 to 0.968)) were significant predictors of MLLA. Conclusion: Patients with lower health literacy are more likely to face higher levels of social deprivation, which may predict amputation following bypass surgery. Enhancing health literacy could play a role in reducing health disparities caused by social deprivation, thereby potentially addressing a vascular James Lind Alliance priority.