Abstract
Purpose: :
To determine rates of visual field progression (RoP) in manifest open angle glaucoma under ordinary clinical care in a large fairly representative patient material.
Methods: :
A majority of diagnosed glaucoma patients in the Malmö metropolitan catchment area receive their primary glaucoma care at the Department of Ophthalmology at Malmö University Hospital. We performed a retrospective chart review including all patients at the department with POAG, NTG and PEX glaucoma with manifest field loss and at least 5 years of follow-up and 5 or more SITA Standard visual field tests during the study period (March 1996 - June 2005), applying minimal exclusion criteria. Rate of visual field progression was determined by a simple linear regression analysis of mean deviation (MD) values over time.
Results: :
583 patients were included, 38% with PEX glaucoma. Mean age at baseline was 71 years, mean follow-up time was 7.8 years, and the mean number of visual fields was 8.9. Mean RoP in the whole cohort was 0.80 dB/year ranging from a maximum progression of 5.58 dB/year to an improvement of 1.24 dB/year. Among all patients 89.4% had negative slopes, and 59.6% of patients had statistically significantly negative slopes (p < 0.05). The distribution of progression rates was negatively skewed and progression rates exceeding 1.5 dB/year were seen in 99 patients (17.0%) and faster than 2.5 dB/year in 26 patients (4.5%).
Conclusions: :
Progression rates varied very much between patients in a relatively representative material of patients with open angle glaucoma under conventional clinical care. A great majority of patients had negative slopes. A large minority had progression rates that correspond to a worsening from normal function to blindness in 20 years or less (i.e. > 1.5 dB/year), and a small group progressed at speeds that correspond to progression from normal to blindness in a dozen years or less (i.e. > 2.5 dB/year).