Glaucoma eye-drop regimens have long been a significant problem for some patients but there is a growing number of strategies and devices available to help improve their adherence to ocular hypertensive therapy.
Among the most common reasons that patients give for their poor use of prescribed IOP drops are difficulties instilling eye-drops, inability to master a technique, physical barriers and medication side-effects.
Recent studies corroborate these patient comments, showing that many glaucoma patients are not administering their drops correctly and suggesting that education about instillation techniques can improve a patient’s ability to instil drops correctly.1
Some studies suggest that optometrists should routinely show patients how to instil drops, watch them as they do it and then assess the patient’s ability to instil drops at each follow-up consultation.
If patients are asked to demonstrate the technique, an opportunity for teaching may present itself if the patient is having difficulty. Demonstrating and teaching proper drop instillation to glaucoma patients using artificial tears can be done by an optometrist or another member of the practice staff who usually trains patients in contact lens insertion and removal.
A study published in the Journal of Glaucoma in March 2012 found that nine out of 10 glaucoma patients were not administering their drops correctly.2 Only six of 70 patients tested ‘were able to correctly instil the eye-drop’, that is, squeeze out one drop and instil it into the conjunctival sac without bottle tip contact.
The study, entitled ‘Evaluating eye drop instillation technique in patients’, focused on the often overlooked cause of adherence problems—the unintentional, improper dosing and instillation of glaucoma medication. The researchers observed 70 primary open-angle and primary angle-closure glaucoma patients, aged from 35 to 70 years, who had been self-administering glaucoma medications for at least six months. Those with arthritis, tremors and other impairments that might interfere with their ability to correctly instil drops were excluded.
Patients were asked to instil one drop from a bottle of artificial tears into one eye using the same technique that they use for glaucoma drops. The number of drops they squeezed out ranged from one to eight.
|Owen Mumford Autosqueeze Eye Drop Dispenser and Owen Mumford Autodrop Eye Drop Dispenser. Reusable, lightweight plastic devices that assist with the application of eye-drops. They are available from Diabetes and Medical Supplies.
It is of concern that 31 per cent dropped the eye-drops on their eyelids or cheeks, and 75 per cent touched the tip of the bottle to their eye or periocular tissue, while only 28 per cent correctly closed their eyes after instilling drops. Just five per cent occluded their puncta.
In another inquiry into adherence strategies,3 entitled the ‘Eye drop instillation technique in patients with glaucoma’ study, researchers found that there was a significant association between education relating to eye-drop instillation technique and the patient’s ability to instil drops correctly.
In the study, participants used self-administered topical medication for glaucoma or ocular hypertension and were asked to demonstrate how they usually instil eye-drops using a 5 ml bottle of sterile artificial tear solution.
Pfizer’s Xal-Ease plastic eye-drop dispenser and cap opener suitable for use with Xalatan and Xalacom eye-drops. The dispenser is available from Ophthalmologist FOC and can be ordered in by the patient’s chosen pharmacist from Pfizer. It is complimentary for Xalatan/Xalacom patients.
More than half—54.1 per cent or 46 of 85 patients—had a poor drop technique, 11.8 per cent missed the eye, 15.3 per cent touched the tip of the bottle to the bulbar conjunctiva or cornea, and 27.1 per cent touched the eyelid or lashes with the bottle tip. Most—81.2 per cent—could not recall being shown how to instil eye-drops but previous instruction regarding drop instillation technique was significantly associated with good technique and increasing age was associated with poor technique.
The study authors recommended that the assessment of a patient’s ability to instil eye-drops correctly should be a routine part of a glaucoma examination.
Therapeutically-endorsed Gippsland optometrist Ken Thomas believes the biggest adherence issue is getting elderly, immobile patients to maintain regular contact with either an optometrist or an ophthalmologist.
‘I am concerned that a number of patients, especially in rural areas, simply rely on their GP repeating the glaucoma script, and do not receive appropriate monitoring of intra-ocular pressures, fields and optic nerve head appearance,’ he said. ‘The challenge for our profession is to try and stop these people “falling through the cracks”.’
Working in a rural area, he often has patients alternate visits between him and their ophthalmologist, or primarily see him and have infrequent trips to their ophthalmologist.
‘This is primarily to minimise their travel. Glaucoma patients generally are in the older age group, they often don’t drive and often have co-morbidities that contribute to mobility issues,’ he said. ‘This can make it difficult to get to their specialist. They are often dependent on family or friends to take time off work to transport them to Melbourne and they don’t like to impose on them.
‘Many patients appreciate the fact that field testing and OCT scans have lower cost when performed in an optometric setting compared to an ophthalmological clinic, and we are happy to provide copies of these reports for our patients to present to their glaucoma specialist.’
Thomas says the high use of prostaglandins (nearly 50 per cent of PBS glaucoma prescriptions) and increasing uptake of combination agents (29 per cent of PBS glaucoma scripts) means most patients are on monotherapy and require only one drop per day.
‘This is a huge advantage in ensuring adherence to the treatment regimen. Ensuring that the drop is always taken at the same time of day is important for compliance, more than for IOP control,’ he said. He suggests to patients that it might help if they stick a permanent note near their toothbrush, to remind them to have their eye-drops.
‘If patients report difficulty with their drops, I usually instruct them to lie back, close their eyes and apply the drop to the inner canthal region,’ Thomas said. ‘Then the eyes are opened and this achieves adequate delivery of the medication. Most patients are surprised to hear that the eye retains only one-fifth to one-tenth of an eye-drop.’
Thomas doesn’t usually recommend eye-dropper aids but says they work well for some patients.
Side-effects can be another reason for poor adherence.
‘Alpha agonists have a high rate of allergic reaction, with up to 25 per cent of patients developing a problem. Median time for these follicular or dermatological reactions is 12 months so often the optometrist will be the first person to notice this change,’ he said. ‘Other reactions other than redness are not commonly encountered. It is vital for the optometrist to communicate with the initiating ophthalmologist before changing any medications.’
Head of the Sydney Eye Hospital Glaucoma Unit, Glaucoma Australia president and Clinical Associate Professor of Ophthalmology, University of Sydney, Professor Ivan Goldberg said that probably about two-thirds of glaucoma patients were non-compliant but suggested the term ‘non-adherence’ be used.
|The Opticare eye-drop dispenser fits securely around the eye, prevents touch contamination and ensures that drops go into the eyes and not down the cheek. The UK-designed product is sold in Australia by the Melbourne-based distributor Intelligent Health Systems.
‘It’s a very complicated area of study with wide variations in the reasons different patients don’t adhere,’ he said. ‘Some are personal reasons including disease “philosophy”, understanding and education, while for others there are socio-economic reasons. Some have side-effect induced reasons and others have physical barriers to self-administration—“discompliance”—such as tremor, arthritis, muscle weakness and poor hand-eye co-ordination.
‘Some reasons are disease-related and while glaucoma is relatively asymptomatic, chronic and incurable, progress is often slow so there is no immediate “price” paid by the patient that they notice for omitted medications.
‘This truly needs to be individualised if solutions are to be found to help each patient, as each is unique and what motivates and influences long-term adherence and persistence varies enormously and might well change for an individual over time,’ Goldberg said.
|Autodrop Eyedrop Dispenser. A plastic dispenser, shaped and contoured to fit over a bottle of eye-drops, and around the eye socket to assist with easy, accurate dispensing of drops. Available in Australia from Diabetes and Medical Supplies.
Professor Goldberg suggested various aids be mentioned so patients can consider them when necessary. ‘Pfizer did some work with its Xalatan-bottle device and found it was a significant aid for 50 per cent of patients,’ he said. ‘Alcon also did work with its Travatan Dosing Aid (TDA) and found a similar figure. One of the challenges is that the various bottles are so different. What would work for a bottle of Xalatan won’t work for Cosopt.
The national executive officer of Glaucoma Australia, Geoff Pollard, said the organisation supplied a limited number of free aids depending on the eye-drop manufacturers supplying them to the foundation.
- Waterman H, Evans JR, Gray TA, Henson D, Harper R. Interventions for improving adherence to ocular hypotensive therapy. Cochrane Database Syst Rev 2013; 4: CD006132. doi: 10.1002/14651858.CD006132.pub3.
- Gupta R, Patil B, Shah BM et al. Evaluating eye-drop instillation technique in glaucoma patients. J Glaucoma 2012; 21: 3: 189-189.
- Tatham AJ, Sarodia U, Gatrad F, Awan A. Eye drop instillation technique in patients with glaucoma. Eye 2013; 27: 1293-1298. doi:10.1038/eye.2013.187.