Abstract
Abstract: :
Purpose: To study the circadian pattern of intraocular pressure (IOP) in a group of newly diagnosed, untreated glaucoma patients. Methods: Twenty-eight newly diagnosed, untreated glaucoma patients (ages 40-80 years) were entrained to a 16-hour wake and 8-hour sleep cycle for a week. At the end of entrainment, IOP was measured using a pneumatonometer every 2 hours in a sleep laboratory. During the diurnal (wake) period, supine IOP, systolic and diastolic blood pressures, and heart rate were measured after a 5-minute bed rest. Then, IOP was measured after 5 minutes in the sitting position. During the nocturnal (sleep) period, IOP, systolic and diastolic blood pressures, and heart rate were measured supine. Mean supine and sitting IOP, blood pressures, and heart rate in the diurnal period and in the nocturnal period were calculated. Data of supine and sitting IOP, blood pressures, and heart rate obtained under the same experimental conditions from an age-matched group of 28 healthy individuals were used for a comparison. Results: Mean diurnal IOP, either sitting or supine, and mean nocturnal supine IOP in glaucoma patients were significantly higher than those in healthy individuals. However, the diurnal-nocturnal IOP change was less in glaucoma patients, considering either the sitting-supine body position or the supine-supine body position. There was a nocturnal decrease of systolic blood pressure in glaucoma patients, but not in healthy individuals. The nocturnal changes of diastolic blood pressure and heart rate were not significant in both glaucoma patients and healthy individuals. Conclusion: Both diurnal and nocturnal IOP in these newly diagnosed, untreated glaucoma patients are higher than those in healthy individuals. The diurnal-nocturnal IOP change is less in these glaucoma patients and there is a nocturnal decrease of systolic blood pressure.
Keywords: 444 intraocular pressure • 349 circadian rhythms • 331 blood supply