Simultaneous 24-hour monitoring of intraocular pressure and arterial blood pressure in patients with progressive and non-progressive primary open-angle glaucoma.
We measured and compared diurnal and nocturnal blood pressure (BP) with the Space Labs Holter in progressive and non-progressive glaucomatous patients with a satisfactory diurnal control of IOP in order to identify any link between a progressive worsening of their visual field (VF) defects and the characteristics of their nocturnal BP "dip". Ambulatory 24-hour BP monitoring and inpatient IOP curves were done on two consecutive days on 36 patients (17 women, 19 men, mean age 67.44 +/- 8.06 years) with moderate to severe POAG and good diurnal therapeutic control of IOP (daytime IOP < or = 21 mm Hg). Depending on the stability or progression of their VF defects during the last two years, the patients were classified in two groups: the progressive group comprised 24 patients (14 women, 10 men) and the stable group 12 patients (9 men, 3 women). We compared local and systemic risk factors for POAG, mean and maximum daytime and nighttime IOP in each group. The mean systolic and diastolic daytime BP, mean systolic and diastolic nighttime BP and the nocturnal systolic and diastolic BP dip were calculated for each patient. The distribution of these parameters was then statistically compared with normal reference values and for the two groups. The groups were closely comparable as regards their IOP 24-hour profile. The overall mean daytime, nighttime, and nocturnal dips fell within the normal range of the reference population. We found a significanty smaller systolic and diastolic BP dip in the progressive group and a broader distribution of the lower values both for systolic and diastolyc BP in the progressive group. A broader distribution of the lower values for systolic and diastolic BP dip was also noticed when progressive patients were compared with the reference population. The relative absence of a nocturnal BP dip may be interpreted as another disturbing factor in the self-regulatory mechanisms of the optic nerve head in glaucoma