A marked fall in nocturnal blood pressure is associated with the stage of primary open-angle glaucoma in patients with arterial hypertension.

Introduction: The aim of this study was to assess blood flow in the vessels of the eyeball and changes in the optic nerve in patients with arterial hypertension and primary open-angle glaucoma.
Material and Methods: The patients were divided into groups: 1 (night blood pressure, BP, fall, NBPF, not more than 10%; non-dippers); 2 (NBPF 10-15%, dippers) and 3 (NBPF>15%; extreme dippers).
Results: In the group of dippers and extreme dippers, perfusion pressure was significantly lower than that in the non-dippers group, there was reduced thickness of the nerve fibers and a greater decrease in the visual field. Significant relationships between peak systolic, end-diastolic flow in the ophthalmic and central retinal arteries and night perfusion pressure, thickness of nerve fibers, and a loss of visual field were observed.
Conclusion: In patients with glaucoma and well-controlled hypertension, a nocturnal BP fall of more than 10% is associated with a greater visual field defect and greater degeneration of the optic nerve fibers. Low minimum diastolic pressure and the level of nocturnal BP fall, but not the absolute value of average arterial BP at night, should be included in the group of specific risk factors in patients with hypertension and open-angle glaucoma. These findings also suggest avoiding excessive lowering of BP at night in this group.