Understanding whether differences in the local availability of eye care professionals are related to differences in realized access to eye care is important for assessing whether and where public health efforts are needed to increase access to eye care professionals.
To examine whether the county-level availability of ophthalmologists and optometrists is associated with measures of realized access to eye care for individuals with diabetes mellitus, diabetic retinopathy, or age-related macular degeneration (ARMD).
Design, Setting, and Participants
We studied a cross-sectional sample of US adults 40 years and older (1098 individuals with diabetes, 345 with diabetic retinopathy, and 498 with ARMD) from the 2005-2008 National Health and Nutrition Examination Survey.
Main Outcomes and Measures
Outcomes were whether diabetic individuals reported undergoing a dilated eye examination in the past year, whether individuals were unaware they had diabetic retinopathy, whether diabetic individuals had vision-threatening diabetic retinopathy, and whether individuals were unaware they had ARMD.
In logistic regression models that also included individual characteristics, individuals who lived in a county in the highest ophthalmologist availability quartile were less likely to be unaware they had diabetic retinopathy (predictive margin [PM], 66.1%; 90% CI, 48.8%-83.4%; vs PM, 84.1%; 90% CI, 78.7%-89.6%) and were less likely to have vision-threatening diabetic retinopathy (PM, 1.4%; 90% CI, 0.9%-1.9%; vs PM, 2.6%; 90% CI, 1.8%-3.4%) than individuals who lived in a county in the lower 3 ophthalmologist availability quartiles. Individuals who lived in a county in the lowest ophthalmologist availability quartile were more likely to be unaware they had ARMD (PM, 93.8%; 90% CI, 90.6%-97.0%; vs PM, 88.3%; 90% CI, 84.7%-91.9%) than individuals who lived a county in the higher 3 ophthalmologist availability quartiles. Optometrist availability quartiles were not significantly related to any of the outcomes.
Conclusions and Relevance
The results suggest that efforts to increase access to ophthalmologists to improve outcomes related to diabetic retinopathy or to increase awareness of ARMD should focus on improving access for diabetic individuals who live in counties in the lowest 3 quartiles of ophthalmologist availability and on individuals at risk of ARMD who live in counties in the lowest quartile of ophthalmologist availability.