Ambulatory blood pressure monitoring in glaucoma patients. The nocturnal systolic dip and its relationship with disease progression

Purpose: This study was designed to uncover a new sensitive and specific fa ctor for predicting the progression of glaucoma. Methods: The 24-hour ambul atory blood pressure and diurnal curve of intra-ocular pressure were record ed in seventy patients: 51 primary open angle glaucoma (POAG) and 19 normal tension glaucoma (NTG). The mean systolic, diastolic and average arterial blood pressure were calculated, along with the nocturnal dip of systolic pr essure and diastolic blood pressure. Two-year disease progression was asses sed for all patients by means of retrospective analysis of visual fields de fects on repeated perimetries. Results: Abnormal (absence or increased) noc turnal dip of systolic blood pressure was found to be correlated with disea se progression in POAG and NTG patients with a sensitivity of 86% and a spe cificity of 85%, whereas no significant correlation was found for the other risks factors envisaged. Furthermore, a significant relationship between s table visual field defects and the use of diuretics/laser procedure was evi denced. Conclusion: The nocturnal dip of systolic blood pressure should be considered as a predictive factor of disease progression in NTG and POAG. F urther prospective studies are needed to ascertain whether dip normalizatio n could help slow down the visual field loss in these patients.