Age is an important risk factor for glaucoma, a chronic degenerative disease affecting the optic nerve and it is characterised by damage progressive of its constituent nerve fibres and consequent visual field damage. If left untreated, the progressive reduction of the visual field can lead to blindness. Several studies report that the incidence of glaucoma in the elderly population has increased in recent years. However, the availability of ophthalmic treatments for this condition has also increased and many researchers have focused on studying anti-glaucomatous eye drops and adherence to prescribed therapy.
One problem with the use of eye drops is the difficulty of application, especially in older patients. It is estimated that a percentage of older patients, ranging from 30% to 90%, administer the drops themselves. Therefore, many have stressed the importance of teaching glaucoma patients the correct use of self-administration eye drops, which are often supplied in single-use containers. Single-dose eye drops, in fact, contain no preservatives and can offer several advantages to patients, including a lower risk of contamination. However, several studies have shown that self-application of eye drops is particularly difficult in older patients compared to younger patients.
Factors influencing successful self-administration
There are many factors that can influence the successful self-administration of eye drops for the treatment of glaucoma.
Many articles, for example, have addressed the issue of physical limitations in older people, who may have hand tremors or less tactile sensitivity, difficulty in reclining the head back or loss of the visual field. Any of these factors, or a combination of them, can significantly interfere with the proper application of drops and can cause repeated injury or irritation to the ocular surface.
When no physical or mental impediments are present in older patients, the difficulties in application seem to lie in the type of bottle used.
In fact, a recent studieso found that difficulties in the self-application of eye drops occur especially in the case of disposable containers, as opposed to multi-dose bottles, probably because they are more difficult to open and press out drops.
Furthermore, the study found that in older patients, contamination of the tip of the monodoses occurs more often and, due to carelessness, comes into contact with the ocular surface, causing injury and infection.
Another recurring problem is injuries to the cornea, which can be injured by nails during application. On the other hand, no difference in self-application ability was found between the two sexes, while visual acuity of the better eye and previous experience with disposable eye drop containers were a discriminating factor for successful administration.
The problem of poor grip
All the factors we have examined that cause difficulties in self-administration of eye drops are obviously related to poor treatment adherence. Furthermore, studies have shown that this aspect is often underestimated by glaucoma patients. In particular, a study involving a group of glaucoma patients over 65 years of age found a non-adherence rate of 23%. A remarkable percentage that highlights the need to educate patients, especially older ones.
The study also showed that many of the patients are convinced that they apply eye drops correctly, whereas this is not true in about half of the cases. Unfortunately, it must also be taken into account that many patients in old age do not have the possibility of calling on the help of another person for administration.
In conclusion, in elderly patients there is a correlation between the ability to self-administer and the format of the device containing the drops, as well as with previous experience of self-application.
For this reason, it is important to ask the doctor, without fear, to be instructed in the self-administration of eye drops and to be checked at regular intervals to verify the success of the therapy. If you do not notice an improvement in the condition due to incorrect self-administration, it would be better to resort to a help with applicationby family members or specialised personnel, to avoid treatment failure and the occurrence of possible infection or injury due to contact of the bottle with the ocular surface.
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