Central corneal thickness and measured IOP response to topical ocular hypotensive medication in the Ocular Hypertension Treatment Study.
OBJECTIVE
To determine whether central corneal thickness (CCT) correlates with measured intraocular pressure (IOP) response to topical ocular hypotensive medication in the Ocular Hypertension Treatment Study (OHTS).


METHODS
Prospective randomized clinical trial.


METHODS
Intraocular pressure measurements were performed by Goldmann applanation tonometry. Central corneal thickness was measured by ultrasonic pachymetry. The following indicators of IOP response to topical ocular hypotensive medication were examined: (1) IOP after an initial four- to six-week one-eyed therapeutic trial of a nonselective beta-blocker (N = 549) or a prostaglandin analog (N = 201); (2) the mean IOP response during 12 to 60 months of follow-up among medication participants (N = 689); (3) the percentage of follow-up visits at which both eyes met the treatment goal; (4). the total number of different medications prescribed to reach treatment goal; and (5) the total number of different medications prescribed multiplied by the number of months each medication was prescribed.


RESULTS
Central corneal thickness was inversely related to the IOP response after the initial one-eyed therapeutic trial and during 12 to 60 months of follow-up (P < .05). Mean CCT was not correlated with the number of different medications prescribed during follow-up, the total medication-months, or the percentage of visits at which IOP target was met.


CONCLUSIONS
Individuals with thicker corneas had smaller measured IOP responses to ocular hypotensive medication than those with normal or thin corneas. We believe that CCT measurements may be useful in patient management and in interpreting clinical trials of ocular hypotensive medication.
Brandt
James D
JD
Department of Ophthalmology, University of California, Davis, Sacramento, California, USA.
Beiser
Julia A
JA
Gordon
Mae O
MO
Kass
Michael A
MA
D000287:Administration, Topical; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001837:Body Weights and Measures; D003315:Cornea / Q000473:pathology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000188:drug therapy; D011446:Prospective Studies; D011465:Prostaglandins, Synthetic / Q000627:therapeutic use; D014065:Tonometry, Ocular
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D011465:Prostaglandins, Synthetic