Abstract
Purpose :
Better eye mean deviation (BEMD) of ≤-14 dB carries a 92% probability of failure when testing a glaucoma patient’s legal fitness to drive. We performed a retrospective, observational clinical study to investigate baseline characteristics and factors influencing the rate of progression to BEMD of ≤-14 dB within 10 years of baseline visual field (VF) testing.
Methods :
Rate of progression (dB/yr) data were calculated using serial VFs from our Medisoft electronic database for 865 glaucoma patients, predominantly of European or Afro-Caribbean ancestry. Baseline mean deviation (MD) and index of multiple deprivation (IMD) scores were collated, as well as central corneal thickness (CCT), baseline intra-ocular pressure (IOP) and vertical cup-to-disc ratio (VCDR).
Associations between rate of progression and age, sex, ethnicity, MD, IMD score, CCT, IOP and VCDR were assessed using ANOVA and univariable and multivariable stepwise linear regression models.
Pearson’s chi-squared correlation and logistic regression models were used to assess the associations between baseline characteristics and the actual or predicted progression to loss of driving vision within 10 years.
Results :
The mean age of the cohort was 62.5 years (SD 13.7); 45.9% were European and 42.0% Afro-Caribbean ancestry. The mean rate of progression was -0.351 dB/yr (95%CI: 0.321-0.382, SD=0.459).
In stepwise multivariable modeling, log-transformed rate of progression was independently associated with older age at presentation (β=-0.008, p<0.001), higher IMD score (β=-0.004, p=0.018) and MD at baseline (β=0.047, p<0.001).
Using logistic regression modeling, there was an association between those with predicted loss of driving vision and both MD at baseline (β=0.44, p<0.001) and IMD score (β=-0.023, p=0.043).
Conclusions :
Faster VF progression appears to be significantly associated with older age at presentation, worse baseline MD and higher IMD (signifying a greater level of local socioeconomic deprivation). Both MD and IMD are also associated with an increased likelihood of progression to loss of driving vision within 10 years. These may be important variables to stratify patients at risk of progression and therefore help prioritize clinical resource utilization.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.