To further understand the systemic and ocular risk factors for rapid glaucoma progression, investigators examined a cohort of rapid and nonrapid disease progressors.
Investigators compared medical histories and clinical features of 54 rapidly progressing glaucoma eyes (≥1dB mean deviation (MD)/year) with 486 non-rapidly progressing eyes(<1 dB MD/yr). All patients underwent at least 5 Humphrey visual field (HVF) tests, and had less than 5 dB MD variation between visits.
The mean rate of visual field loss for rapid progressors was -1.55 dB/yr while nonrapid progressors was -0.24 dB/yr.
A regression analysis revealed that individuals with a history of cardiovascular disease had a significantly higher risk of rapid progression (OR 2.33) despite having lower baseline IOP. After adjustment for confounding variables, other significant factors included worse baseline MD, lower baseline IOP, more frequent medication changes and IOP-lowering surgeries.
This study was retrospective, which is limited by selection bias and relies on accurate documentation of risk factors. The authors included patients seen been 1991 and 2015, but the mean length of follow up was not identified.
HVF progression was defined based on MD, as earlier VF tests did not have guided progression analysis software capable of targeting localized change associated with glaucoma. Guided progression analysis may be able to better identify rapid progressors that may have been overlooked based on MD values.
Finally, there were no structural measurements reported such as cup-to-disc ratio or retinal nerve fiber layer measurements that could corroborate glaucoma progression diagnosis.
This study identifies cardiovascular disease as a major risk factor for rapid progression of glaucoma, despite lower baseline IOPs. As we work to identify the pathophysiology of glaucoma disease and progression, this provides further evidence that decreased ocular perfusion pressure and impaired vascular autoregulation can contribute to disease progression.