To determine whether candidate pharmacodynamic (β-adrenergic receptor) and pharmacokinetic (cytochrome P450 2D6) gene polymorphisms are associated with the intraocular pressure (IOP) response to topical β-blockers.
Medical records of 18 773 adults in the Personalized Medicine Research Project were searched to extract all IOP measurements for subjects who had been prescribed a topical β-blocker. Five single-nucleotide polymorphisms in the β1-, β2-, and β3-adrenergic receptor genes and 6 polymorphisms in the CYP2D6gene were genotyped.
A total of 58.1% of the subjects were female; the mean age was 63.8 years. Topical β-blockers were prescribed for 343 eyes of 215 subjects. An IOP reduction of 20% or more in 1 or both eyes was observed in 61.0% of subjects. Men were significantly more likely than women to have an IOP decrease of 20% or more (69.3% vs 54.9%, respectively; χ2 = 4.48; P = .04). After adjusting for sex, family history of glaucoma, and use of systemic β-blockers, subjects with the CC genotype at coding single-nucleotide polymorphism rs1042714 in the ADRB2gene were significantly more likely to experience an IOP decrease of 20% or more (odds ratio, 2.00; 95% confidence interval, 1.00-4.02).
We found that a coding single-nucleotide polymorphism in ADRB2is associated with an increased likelihood of a clinically meaningful IOP response to topical β-blockers.
Because topical β-blockers are the least expensive class of agents used to lower IOP, genotype-based drug prescribing could save health care dollars.