Functional health literacy in patients with glaucoma in urban settings

Objective: To assess the relationship between health literacy and compliance, disease awareness, and disease progression in patients with glaucoma. Methods: A cross-sectional observational study of 204 English-speaking patients treated for glaucoma for at least 1 year at Kresge Eye Institute was conducted. Health literacy was assessed using the standardized Test of Functional Health Literacy in Adults (TOFHLA). An oral questionnaire assessed patients' demographic information and glaucoma understanding. A retrospective medical record review was conducted to record parameters indicating glaucoma severity. Results: One hundred two participants (50%) were categorized as having poor functional health literacy ( mean [SD] TOFHLA score, 18.4 [7.5]) and 102 participants ( 50%) had adequate health literacy ( mean [ SD] TOFHLA score, 42.8 [5.1]). The poor health literacy group showed significant differences in income, education, medication compliance, glaucoma understanding, and missed appointments compared with the adequate health literacy group ( P <. 001). Patients with poor health literacy showed a greater visual field loss on initial presentation ( mean deviation [SD], -10.58 [9.3] dB) compared with the adequate health literacy group ( mean deviation [ SD], -7.79 [6.9] dB; P=.02) and significantly worse visual field parameters when comparing pattern SDs on the recent and the initial visual fields ( pattern SD change [ SD], 0.19 [2.5] dB in the poor health literacy group vs -0.7 [2.2] dB in the adequate health literacy group; P=.02). Conclusions: Patients with poor health literacy had poorer compliance, worse disease understanding, and greater disease progression compared with the adequate health literacy group, highlighting the need to promote health literacy in patients with glaucoma.