Results of the betaxolol versus placebo treatment trial in ocular hypertension.
OBJECTIVE
To determine whether treatment with betaxolol can delay or prevent the conversion from ocular hypertension to early glaucoma on the basis of visual field criteria, by means of a prospective, randomised, placebo-controlled trial.


METHODS
Three hundred and fifty-six ocular hypertensives were randomized to treatment with either betaxolol drops or placebo drops during the period 1992-1996. Each patient was followed prospectively with 4-monthly visits. Examination at each visit included visual field testing, intra-ocular pressure (IOP) measurement and optic disc imaging. Conversion to early glaucoma was defined on the basis of visual field change by AGIS criteria. An intent-to-treat analysis compared visual field conversion after 3 years in the treatment and placebo arms. Normal visual field survival analysis was also performed. The IOP characteristics of the two treatment groups were compared.


RESULTS
Two hundred and fifty-five patients completed the study, which ended in 1998, with a range of follow-up of 2-6 years. Sixteen (13.2%) of 121 patients in the placebo group converted to glaucoma, compared with 12 (9.0%) of 134 patients in the betaxolol group. The intent-to-treat analysis demonstrated no evidence of any difference in conversion rates between the betaxolol and placebo groups after 3 years. Visual field survival analysis demonstrated no significant difference between the betaxolol and placebo groups. The betaxolol-treated group had significantly lower post-treatment IOP values. Converters had significantly higher pre- and post-treatment IOP values than non-converters.


CONCLUSIONS
Betaxolol significantly lowered the IOP level compared with placebo. Conversion to glaucoma was found to be related to both the baseline and post-treatment IOP levels. However the intent-to-treat analysis did not demonstrate a statistically significant reduction in the conversion rate in the betaxolol-treated group.
Kamal
Deborah
D
Glaucoma Research Unit, Moorfields Eye Hospital, City Road, London, EC1V 2PD UK.
Garway-Heath
David
D
Ruben
Simon
S
O'Sullivan
Fiona
F
Bunce
Catey
C
Viswanathan
Anath
A
Franks
Wendy
W
Hitchings
Roger
R
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000368:Aged; D015784:Betaxolol / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000517:prevention & control; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D009798:Ocular Hypertension / Q000175:diagnosis / Q000188:drug therapy*; D009883:Ophthalmic Solutions; D011446:Prospective Studies; D014794:Visual Fields / Q000187:drug effects
D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D015784:Betaxolol