Abstract
Purpose: :
Elements of the patient-provider relationship influence the way in which patients with glaucoma self-manage their disease. Trust, one element of this complex relationship, is associated with patients’ satisfaction with care. Previously, we reported that glaucoma patients’ measured trust in the physician is significantly lower for non-white patients than for white patients. Considering this, we hypothesized that lower trust in the physician is associated with worse visual outcomes in glaucoma, especially for non-white patients.
Methods: :
The study was designed to assess the long-term visual outcomes of a cohort of subjects with glaucoma previously enrolled in a survey study. In the original study, subjects performed a test of their trust in their physician with a validated instrument, the Trust in Provider Scale (TPS). Subjects were included in the current study if they had a diagnosis of open-angle glaucoma and baseline visual field tests as well as visual field tests at least two years later. The primary outcome was glaucoma-related blindness, defined as a visual field defect within 20 degrees of fixation in at least one eye.
Results: :
For the 60 subjects included, scores on the TPS, scaled 0-100, ranged 59.1-100.0, mean 77.4+7.3, median 75.0. Subjects with glaucoma-related blindness in at least one eye scored lower on the TPS (n=21, TPS score 74.9+7.4) than subjects without blindness (n=39, TPS score 78.8+6.9; p=0.04). Considering white subjects only, the TPS scores were similar for blind (n=12, TPS score 77.1+7.7) versus not blind subjects (n=10, TPS score 76.4+6.7; p=0.82). For non-white subjects, TPS scores were significantly lower for blind (n=9, TPS score 72.0+6.2) versus not blind subjects (n=29, TPS score 79.6+6.9, p=0.82).To further explore the relationships between race, trust, and blindness, we considered race and trust together as explanatory factors for glaucoma-related blindness. In this multiple regression model (AUC=0.81), non-white race and TPS score were associated with blindness, p=0.03. The interaction between race and trust was significant, p=0.007, indicating that the increase in odds for blindness with each unit decrease in TPS score was different for white versus non-white subjects.
Conclusions: :
Glaucoma patients’ trust in the physician is associated with glaucoma-related blindness in this study. While it is likely that disease severity influences the patient-provider relationship, the converse may be true as well, perhaps through variable medication adherence or follow-up. The association between lower trust in the physician with blindness in patients of non-white race deserves further attention as we strive to reduce the racial disparities in visual outcomes prevalent in glaucoma.
Keywords: clinical (human) or epidemiologic studies: health care delivery/economics/manpower