To determine the relationship between mean deviation (MD) scores and resource utilization among glaucoma patients in the United States and Europe.Methods
A retrospective analysis of patient in the United States (June 1990 to January 2003, N=151) and Europe (June 1994 to July 2003, N=194) was conducted. Office visits, pressure-lowering medications, visual field examinations, and glaucoma surgeries were recorded with age, intraocular pressure (IOP), and MD. Patients with missing MD and IOP were excluded; final sample sizes were 130 in the United States and 161 in Europe. Fixed effects and logistic regression models assessed the associations between MD and visits, medication, examinations, and surgery.Results
Number of office visits and visual field examinations significantly increased but the number of glaucoma medications decreased as MD worsened and IOP increased. Odds of trabeculoplasty within 2 years decreased by 8.1% in the United States and 9.9% in Europe with every 1.0 dB improvement in MD. Odds of trabeculectomy within 2 years increased by 13.9% in the United States and by 18.6% in Europe with every 1 mm Hg increase in IOP. In the United States, odds of trabeculectomy within 5 years increased by 12.2% with each 1.0 dB worsening in MD.Conclusions
MD is associated with resource utilization in glaucoma patients. Evidence supporting use of MD to predict surgery is less conclusive, possibly due to the relative low frequency of surgeries. Therapies aimed at stabilizing visual field deterioration may reduce resource use and costs associated with glaucoma; however, more research is necessary to establish whether such treatments meet common standards of cost-effectiveness.