Brimonidine .2% as a replacement for beta blockers in geriatric patients with glaucoma

[Selective α2-agonists in the treatment of glaucoma: pharmacology, efficacy and safety]

Glaucoma is the main cause of irreversible blindness in the world. Among the hypotensive eye drops, an important place belongs to the selective α2-adrenergic receptor antagonist brimonidine. This part of the review focuses on key pharmacological and therapeutic characteristics of brimonidine and its mode of action. The article also discusses the side effects of brimonidine and the methods of their prevention.

Choosing appropriate patient-reported outcomes instrument for glaucoma research: a systematic review of vision instruments

PURPOSE

To identify vision Patient-Reported Outcomes instruments relevant to glaucoma and assess their content validity.

METHODS

MEDLINE, MEDLINE in Process, EMBASE and SCOPUS (to January 2009) were systematically searched. Observational studies or randomised controlled trials, published in English, reporting use of vision instruments in glaucoma studies involving adults were included. In addition, reference lists were scanned to identify additional studies describing development and/or validation to ascertain the final version of the instruments. Instruments' content was then mapped onto a theoretical framework, the World Health Organization International Classification of Functioning, Disability and Health. Two reviewers independently evaluated studies for inclusion and quality assessed instrument content.

RESULTS

Thirty-three instruments were identified. Instruments were categorised into thirteen vision status, two vision disability, one vision satisfaction, five glaucoma status, one glaucoma medication related to health status, five glaucoma medication side effects and six glaucoma medication satisfaction measures according to each instruments' content. The National Eye Institute Visual Function Questionnaire-25, Impact of Vision Impairment and Treatment Satisfaction Survey-Intraocular Pressure had the highest number of positive ratings in the content validity assessment.

CONCLUSION

This study provides a descriptive catalogue of vision-specific PRO instruments, to inform the choice of an appropriate measure of patient-reported outcomes in a glaucoma context.

Update on the role of alpha-agonists in glaucoma management

Glaucoma is the second most common cause of world blindness (following cataract) with estimated cases reaching 79.6 million by 2020. Although the etiology of glaucoma is multi-factorial, intraocular pressure (IOP) is the only modifiable factor in glaucoma management proven to alter the natural course of the disease. Among various classes of IOP-lowering medications currently available, alpha-adrenergic receptor agonists are used either as monotherapy, as second-line therapy, or in fixed combination with beta-blockers. Non-selective adrenergic agonists such as epinephrine and dipivefrin are infrequently used today for the treatment of glaucoma or ocular hypertension, and have been replaced by the alpha-2-selective agonists. The use of apraclonidine for IOP reduction in glaucoma or OHT is limited due to a high rate of follicular conjunctivitis. The alpha-2-selective agonist in use today is brimonidine. The brimonidine-purite formulations are preferred to brimonidine-benzalkonium chloride (BAC) formulations due better tolerability while maintaining similar efficacy. Brimonidine is also effective when used in combination with a beta-blocker. Using brimonidine-timolol fixed combination (BTFC) as first-line therapy has an added potential for neuroprotection. This would be a valuable strategy for glaucoma treatment, for patients who are intolerant of prostaglandin analogs, or for patients where prostaglandin analogues are contraindicated as first-line therapy, such as in patients with inflammatory glaucoma.

Self-application of single-use eyedrop containers in an elderly population: comparisons with standard eyedrop bottle and with younger patients

PURPOSE

To test whether patients aged >or=80 years can safely and successfully apply eyedrops from a single-use eyedrop container without support, and to compare the results with those of younger patients using single-use containers and older patients using standard eyedrop bottles.

METHODS

Patients aged >or=80 years who had no physical or mental conditions hindering self-application of eyedrops and actually did so because of glaucoma or dry eyes were included consecutively in the study group (n = 44) in order to perform self-application of eyedrops from single-use eyedrop containers. Patients were observed meticulously by two investigators, who documented practical problems during the procedure in a checklist. In control group A (n = 22), glaucoma or sicca patients aged between 50 and 65 years applied drops from single-use eyedrop containers; in control group B (n = 28), glaucoma or sicca patients aged >or=80 years used a traditional eyedrop bottle.

RESULTS

Successful application of the drops into the conjunctival sac was achieved by 57% in the study group (95% and 89% in control groups A and B, respectively). Scratching of the eyedrop container along the conjunctiva or cornea was observed in 68% of the study group (41% and 61% in control groups A and B, respectively). Frequency of problems during opening and self-application of single-use eyedrop containers in the study group showed an inverse correlation to visual acuity in the better eye and previous experience with this kind of eyedrop container.

CONCLUSION

Older patients have massive problems in self-administering eyedrops from single-use containers. Factors influencing the success of self-application may include the patient's previous experience with this kind of eyedrop container and the patient's visual acuity.

Meta-analysis of randomized controlled trials comparing timolol with brimonidine in the treatment of glaucoma

This paper aims to compare the efficacy and tolerability of timolol versus brimonidine in the treatment of glaucoma. Comprehensive searches were performed using Medline, Embase and the Cochrane Controlled Trials Register for randomized controlled trials comparing timolol and brimonidine. Two reviewers independently assessed trials for eligibility and quality and extracted data. A random effects model was used to combine studies. Outcome was defined as the absolute mean intraocular pressure (IOP) reduction from baseline to end-point for efficacy, and relative risk (RR) for adverse events. Subgroup analysis and meta-regression were used to explore heterogeneity according to trial design and quality. Ten publications reporting on eight trials with 2387 participants were included in the meta-analysis. Two further trials were commented on qualitatively. IOP reduction was not significantly different between timolol and brimonidine. Weighted mean difference (WMD) of IOP reduction was 0.24 mmHg (favouring brimonidine) with a 95% confidence interval of -0.57 to 1.04 mmHg. There was significant heterogeneity between studies (chi(2) (13) = 73.75, P < 0.00001, I(2) = 91%). Subgroup analysis showed no significant WMD for studies where data were analysed from end-points >/=6 months or <6 months. Meta-regression analysis showed increased WMD IOP reduction in favour of brimonidine with increased trial quality (t(3) = -4.58, P = 0.01), but no significant association with trial duration (t(3) = 0.73, P = 0.51) or size (t(3) = -0.59, P = 0.57). The RR of ocular allergy was much lower with timolol than brimonidine (RR = 0.08, 95% confidence interval 0.01 to 0.47). Publication bias was not evident on a funnel plot, although the number of studies was small. The conclusion is that both drugs are equally effective in lowering IOP. Brimonidine is associated with a higher rate of allergy.