Disparity of Geographic Access to Ophthalmic Manpower and Its Relationship to Diabetic Retinopathy

This study aimed to identify existence of any socio-demographic disparity of geographic access to ophthalmic manpower and determine its association with prevalence of diabetic retinopathy in Mississippi. Great circle distances between block group centroid and identified 168 eye centers with ophthalmologists were determined. Data on socio-demographic characteristics of each block group were downloaded from 2000 US Census CD. Retinopathy rate was obtained from MS-BRFSS data from 2000 to 2006 and the prevalence was weighted according to age, gender and race and assigned into each block group. Logistic regression analyses were conducted to test existence of difference in distance among subgroups of community characteristics. Generalized Additive Model (GAM) was used for visually examining the relationship between retinopathy and distance.

The majority of patients (55%) should travel 5 or more miles to get access to ophthalmologist. Logistic regression analyses revealed that block groups associated with less miles had a higher proportion of people with high median house values, high median income and more than 12 years education. Higher proportions of blacks and people older than 65 years were found in longer miles. The graph created from GAM controlling major socio-demographic variables demonstrated that retinopathy rate went down as distance increased and started increasing once distance reached 7.1 mile where retinopathy rate is the lowest (d.f.=4, p<0.001).

Our data suggested that risky groups are remote from ophthalmic manpower and retinopathy was associated with geographic distance. Geographic distance should therefore be considered when planning state-wide ophthalmic manpower programmes for high risk populations.