Comparison of disease severity in glaucoma patients identified by screening in the 1990s and in routine clinical care in the 2010s in Sweden

Abstract

Background and Purpose: In a previous study comparing the amount of visual field damage at presentation in patients having open-angle glaucoma (OAG) identified through screening and in patients diagnosed in routine clinical practice in the 1990s, the damage was considerably worse in the clinically diagnosed patients. In the present study we compare visual field damage at presentation in the same 402 screened patients with that seen in 281 newly detected previously untreated patients clinically diagnosed in the 2010s. Methods: The perimetric visual field index mean deviation (MD) was compared in the two groups of patients. Results: In the clinical patients diagnosed with bilateral visual field damage the median MD was −5.1 dB in the better eye and −13.0 dB in the worse eye. In the screened patients the median MD in the better eye was −6.5 dB and −11.5 dB in the worse eye. The differences between the clinical and screened patients were non-significant, p = 0.28 and p = 0.67 respectively. More clinical patients had severe visual field loss, defined as MD less than −20 dB, in the worse eye than in the screened patients, 18.5% versus 12.7% respectively, p = 0.037. Conclusion: The visual field damage at presentation in clinically diagnosed OAG patients has improved in the past 20 years, but the proportion of patients with severe visual field loss in at least one eye, almost 20%, is still unacceptably high considering that severe visual field damage at presentation is the most important risk factor for later development of glaucoma blindness.