Comparison of ambulatory blood pressure values in patients with glaucoma and ocular hypertension

To compare systemic arterial blood pressure (BP) and nocturnal hypotension in patients with normal-tension glaucoma (NTG), high-tension glaucoma (HTG), and ocular hypertension.

Systemic BP was recorded by a portable automated BP monitoring device every 20 min during the day and every 30 min at night in patients with NTG (n=18), HTG (n=22), and ocular hypertension (n=19). Mean systolic, diastolic, and mean arterial BPs were calculated for 24 h, during the day and at night. The mean and maximum nocturnal dip rates were determined for each patient. The number of readings that declined below 90 mmHg for systolic BP and below 60 and 50 mm Hg for diastolic BP was recorded for each group. Statistical significance was set at P<0.05.

Minimum, maximum, and mean values of the systolic, diastolic, and mean arterial BPs were not significantly different among groups. There was no difference among groups in the nocturnal dip percentages of systolic and diastolic BPs. The number of systolic BP readings below 90 mmHg was significantly higher in the NTG group compared with the other groups (P<0.001, chi(2) test).

There may not be any difference among NTG, HTG, and ocular hypertension patients in terms of mean ambulatory BP values. On the other hand, when each individual's ambulatory reading is reviewed, readings may reveal that excessive and repetitive nocturnal drops occur more frequently in some patients with NTG. These hypotensive episodes may be related to the development of glaucomatous damage.