Korean researchers recently found that certain nocturnal diastolic blood pressure measurements are significant predictors of subsequent visual field (VF) progression in eyes with normal-tension glaucoma (NTG). In fact, the dip in nocturnal diastolic blood pressure may be more relevant to future VF progression than a systolic blood pressure drop in these eyes.

This prospective cohort study evaluated 119 eyes of 119 newly diagnosed NTG patients. All participants underwent baseline 24-hour ambulatory blood pressure monitoring, intraocular pressure measurements and at least five serial VF examinations. Subjects were then followed as outpatients at four- to six-month intervals. The associations of VF progression with systolic and diastolic blood pressure measured during the day and at night and other clinical variables were analyzed.

During follow-up, the team found that 41 eyes (34%) showed VF progression. They note that lower nighttime trough and greater nighttime diastolic blood pressure dip ‘area’ at baseline were significant predictors of subsequent VF progression, while none of the systolic blood pressure parameters were associated with VF progression. The researchers add that nocturnal diastolic blood pressure dip showed a greater association with VF progression than systolic blood pressure dip.