OBJECTIVE: The study was performed in early middle-aged African natives with primary open-angle glaucoma to compare the 24-hour intraocular pressure (IOP) variations in healthy versus young glaucoma patients, because IOP follows a circadian (24-hour) oscillation in healthy Caucasians. DESIGN: Case-control study. PARTICIPANTS: Sixteen healthy African volunteers (age 24.5 +/- 1 years, mean +/- standard error of the mean) and 11 open-angle glaucoma African patients (age 36.2 +/- 3.3 years). METHODS: IOP was measured hourly during 24 hours with a Modular One pneumatonometer (Modular One, Digilab, Cambridge, MA), which allows measures in supine subjects. To allow the IOP measurement at night, subjects were awakened under polysomnography (electroencephalogram, electromyogram, electro-oculogram) recorded at night and during a 90-minute afternoon nap. MAIN OUTCOME MEASURES: Hourly IOP values were analyzed for circadian rhythmicity with the Cosinor technique and in relation to the state of wakefulness, light sleep (stages 1 and 2), slow-wave sleep (stages 3 and 4), and rapid eye movement (REM) sleep upon awakening. RESULTS: Sleep patterns did not differ between patients and healthy volunteers. As expected, in the healthy subjects, IOP followed a 24-hour rhythm with a nocturnal peak value (acrophase), and the variations in IOP during sleep were related to sleep structure, being lowest during REM sleep and highest during slow-wave sleep. In the glaucoma patients, however, the 24-hour rhythm of IOP was reversed, with an afternoon acrophase and an early morning trough. CONCLUSIONS: These data suggest a circadian phase shift in IOP in glaucoma patients, with maintained relation to sleep structure.
OBJECTIVE: The study was performed in early middle-aged African natives with primary open-angle glaucoma to compare the 24-hour intraocular pressure (IOP) variations in healthy versus young glaucomapatients, because IOP follows a circadian (24-hour) oscillation in healthy Caucasians. DESIGN: Case-control study. PARTICIPANTS: Sixteen healthy African volunteers (age 24.5 +/- 1 years, mean +/- standard error of the mean) and 11 open-angle glaucoma African patients (age 36.2 +/- 3.3 years). METHODS: IOP was measured hourly during 24 hours with a Modular One pneumatonometer (Modular One, Digilab, Cambridge, MA), which allows measures in supine subjects. To allow the IOP measurement at night, subjects were awakened under polysomnography (electroencephalogram, electromyogram, electro-oculogram) recorded at night and during a 90-minute afternoon nap. MAIN OUTCOME MEASURES: Hourly IOP values were analyzed for circadian rhythmicity with the Cosinor technique and in relation to the state of wakefulness, light sleep (stages 1 and 2), slow-wave sleep (stages 3 and 4), and rapid eye movement (REM) sleep upon awakening. RESULTS: Sleep patterns did not differ between patients and healthy volunteers. As expected, in the healthy subjects, IOP followed a 24-hour rhythm with a nocturnal peak value (acrophase), and the variations in IOP during sleep were related to sleep structure, being lowest during REM sleep and highest during slow-wave sleep. In the glaucomapatients, however, the 24-hour rhythm of IOP was reversed, with an afternoon acrophase and an early morning trough. CONCLUSIONS: These data suggest a circadian phase shift in IOP in glaucomapatients, with maintained relation to sleep structure.
Authors: D L Easty; G Nemeth-Wasmer; J-P Vounatsos; B Girard; N Besnainou; P Pouliquen; L Delval; J-F Rouland Journal: Br J Ophthalmol Date: 2006-05 Impact factor: 4.638
Authors: Sunil P Deokule; Amish Doshi; Gianmarco Vizzeri; Felipe A Medeiros; John H K Liu; Christopher Bowd; Linda Zangwill; Robert N Weinreb Journal: Ophthalmology Date: 2009-02-04 Impact factor: 12.079