Glaucoma and Compliance with Therapy: Strategies for and Barriers to Success
Glaucoma is the leading cause of blindness worldwide, affecting more than 70 million people. Early and consistent therapy is crucial for the preservation of remaining vision in patients with the disease. However, there are many factors that can lower compliance rates and cause non-adherence to treatment plans, which has reported rates of 30-80%. 
Beliefs and Lack of Knowledge about Glaucoma and Treatment Methods
Many studies have found that patients diagnosed with glaucoma may not truly understand the potential for severe, vision-threatening consequences with inadequately treated disease, and the potential benefits of adherence to the treatment plan developed by the ophthalmologist.      As a largely asymptomatic disease, it may be difficult for patients to appreciate disease progression with non-adherence or conversely preservation with appropriate use of therapy. This leads to a lack of trust and faith in the treating physician, which can increase the likelihood that a patient will be non-adherent to their medications.   
The low level of knowledge by the general public about the manifestations of glaucoma and the threat of vision loss that comes along with the disease also plays an important role in the low rates of adherence that is seen among these patients. This also can be attributed to poor health literacy, which is seen among patients dealing with a wide array of conditions, but especially glaucoma patients.   
Difficulty with Obtaining and Administering Eye Drops
Another important factor that affects adherence rates is the difficulty that is reported by patients when trying to obtain glaucoma medications. Cost is a significant barrier to accessing care for many patients, and this has been seen in multiple settings and patient populations.     Even when patients are able to obtain their medications, many experience difficulties with administering drops. This can be attributed to difficulties reading the print on the bottle, forgetfulness, the effects of other chronic conditions increasing the difficulty of managing glaucoma,    and difficulties with applying the correct amount of force and having adequate visual acuity and dexterity to only get the number of drops desired,   among other factors.
Strategies and Interventions to Increase Adherence
There have been many studies into interventions and strategies that have been shown to improve adherence to a glaucoma treatment plan. Most of these work to specifically address barriers discussed above. For example, incorporating discussions of beliefs about glaucoma and treatment methods will help to address misinterpretations of the disease and also help to build trust in the patient-physician relationship, especially when patient-centered communication is used, leaving the patient feeling like an active participant in their own healthcare.  
Another method to improve adherence involves improving health literacy as a whole in this patient population, especially among those newly diagnosed or those struggling with non-compliance. This has been completed using videos discussing glaucoma, including the anatomy of the eye and examples of what vision loss in glaucoma looks like, and also the potential treatment options available and instructions for their use.  
Difficulties with medication bottles, whether reading the print or just forgetting to use them, are common and multiple interventions have been successful in combatting this. Some options include personalized mail and phone call reminders of appointments and medication administration times. One important development of note in this area involves the development of the EyePhone© App, which provides notifications and reminders of current medical treatment, and it has been found to significantly increase glaucoma treatment adherence and improve quality of life.
Another issue that can be addressed through upcoming technological interventions is the struggle of administering only one drop at a time. A contributing factor is the significant variability that has been noted between bottles in terms of the amount of force needed to produce one drop. This can lead to multiple drops being used, and thus early exhaustion of drop supply, which has been found to be fairly common in a pilot study of glaucoma patients. A team from University of California – San Diego is working to establish the use of a smart electronic eyedrop bottle that measures the number of single- and multiple-drop deliveries and provides a potential solution for remote glaucoma eyedrop monitoring. Another promising development in this space is the use of a nose-pivoted drop delivery device, which was found to improve eye drop delivery success, reduce bottle tip contact, and decrease the number of eye drops wasted, leaving it strongly preferred by patients over a traditional drop delivery system.
Lastly, it is important to mention a shift in treatment protocol for glaucoma away from the medication-first model to the early and repeated use of selective laser trabeculoplasty (SLT). SLT involves the use of a Nd:YAG laser to improve drainage through the trabecular meshwork, thus lowering intraocular pressure (IOP). In a recent systematic review, SLT was proven to be effective at lowering IOP with high success rates, even after a single treatment, and has the added benefit of being independent of a patient’s capacity to remain compliant with a treatment plan. The Clarifying the Optimal Application of SLT Therapy (COAST) Trial is being initiated to determine the utility of low-energy SLT conducted annually as primary treatment for mild to moderate open angle glaucoma.
In summary, treatment non-adherence is frequently seen among glaucoma patients, and is associated with lack of understanding of the threat to vision from glaucoma, mistrust of the treatment plan and the potential benefits of adhering to it, and difficulty affording and using drops. There are many interventions to address these barriers, including “smart” eyedrop bottles to provide remote monitoring of adherence and proper usage of drops, smartphone apps to give personalized reminders of when to use medication, and educational videos to improve health literacy and knowledge about glaucoma and dispel common misconceptions about the disease. Laser treatments are increasingly being advocated as an alternative first line therapy where available, and future therapeutics will likely also consider the difficulties and barriers to frequent eyedrop administration.
- ↑ Parihar JK. Glaucoma: The 'Black hole' of irreversible blindness. Med J Armed Forces India. 2016;72(1):3-4.
- ↑ Schwartz GF, Quigley HA. Adherence and persistence with glaucoma therapy. Surv Ophthalmol. 2008;53 Suppl1:S57-68.
- ↑ Olthoff CM, Schouten JS, van de Borne BW, Webers CA. Noncompliance with ocular hypotensive treatment in patients with glaucoma or ocular hypertension an evidence-based review. Ophthalmology. 2005;112(6):953-961.
- ↑ 4.0 4.1 friedman ds, hahn sr, gelb l, et al. doctor-patient communication, health-related beliefs, and adherence in glaucoma results from the glaucoma adherence and persistency study. ophthalmology. 2008;115(8):1320-1327, 1327.e1321-1323.
- ↑ lacey j, cate h, broadway dc. barriers to adherence with glaucoma medications: a qualitative research study. eye (lond). 2009;23(4):924-932.
- ↑ tsai jc, mcclure ca, ramos se, schlundt dg, pichert jw. compliance barriers in glaucoma: a systematic classification. j glaucoma. 2003;12(5):393-398.
- ↑ sleath b, blalock sj, robin a, et al. development of an instrument to measure glaucoma medication self-efficacy and outcome expectations. eye (lond). 2010;24(4):624-631.
- ↑ 8.0 8.1 subathra gn, rajendrababu sr, senthilkumar va, mani i, udayakumar b. impact of covid-19 on follow-up and medication adherence in patients with glaucoma in a tertiary eye care centre in south india. indian j ophthalmol. 2021;69(5):1264-1270.
- ↑ 9.0 9.1 9.2 kanu ln, jang i, oh dj, et al. glaucoma care of prison inmates at an academic hospital. jama ophthalmol. 2020;138(4):358-364.
- ↑ Stryker JE, Beck AD, Primo SA, et al. An exploratory study of factors influencing glaucoma treatment adherence. J Glaucoma. 2010;19(1):66-72.
- ↑ Lunnela J, Kääriäinen M, Kyngäs H. The views of compliant glaucoma patients on counselling and social support. Scand J Caring Sci. 2010;24(3):490-498.
- ↑ 12.0 12.1 Killeen OJ, Pillai MR, Udayakumar B, et al. Understanding Barriers to Glaucoma Treatment Adherence among Participants in South India. Ophthalmic Epidemiol. 2020;27(3):200-208.
- ↑ Muir KW, Alder B, Thomas A, Crowell SS, Stinnett SS, Lee PP. Trust in the provider and glaucoma-related blindness. ISRN Ophthalmol. 2012;2012:393917.
- ↑ 14.0 14.1 Meier-Gibbons F, Töteberg-Harms M. Influence of Cost of Care and Adherence in Glaucoma Management: An Update. J Ophthalmol. 2020;2020:5901537.
- ↑ Muir KW, Santiago-Turla C, Stinnett SS, et al. Health literacy and adherence to glaucoma therapy. Am J Ophthalmol. 2006;142(2):223-226.
- ↑ 16.0 16.1 Muir KW, Ventura A, Stinnett SS, Enfiedjian A, Allingham RR, Lee PP. The influence of health literacy level on an educational intervention to improve glaucoma medication adherence. Patient Educ Couns. 2012;87(2):160-164.
- ↑ Juzych MS, Randhawa S, Shukairy A, Kaushal P, Gupta A, Shalauta N. Functional health literacy in patients with glaucoma in urban settings. Arch Ophthalmol. 2008;126(5):718-724.
- ↑ Tsai JC. A comprehensive perspective on patient adherence to topical glaucoma therapy. Ophthalmology. 2009;116(11 Suppl):S30-36.
- ↑ Blumberg DM, Prager AJ, Liebmann JM, Cioffi GA, De Moraes CG. Cost-Related Medication Nonadherence and Cost-Saving Behaviors Among Patients With Glaucoma Before and After the Implementation of Medicare Part D. JAMA Ophthalmol. 2015;133(9):985-996.
- ↑ 20.0 20.1 20.2 20.3 Newman-Casey PA, Robin AL, Blachley T, et al. The Most Common Barriers to Glaucoma Medication Adherence: A Cross-Sectional Survey. Ophthalmology. 2015;122(7):1308-1316.
- ↑ Sleath B, Ballinger R, Covert D, Robin AL, Byrd JE, Tudor G. Self-reported prevalence and factors associated with nonadherence with glaucoma medications in veteran outpatients. Am J Geriatr Pharmacother. 2009;7(2):67-73.
- ↑ Stringham J, Ashkenazy N, Galor A, Wellik SR. Barriers to Glaucoma Medication Compliance Among Veterans: Dry Eye Symptoms and Anxiety Disorders. Eye Contact Lens. 2018;44(1):50-54.
- ↑ Jones JP, Fong DS, Fang EN, Mesirov CA, Patel V. Characterization of Glaucoma Medication Adherence in Kaiser Permanente Southern California. J Glaucoma. 2016;25(1):22-26.
- ↑ Asefzadeh B, Rett D, Pogoda TK, Selvin G, Cavallerano A. Glaucoma medication adherence in veterans and influence of coexisting chronic disease. J Glaucoma. 2014;23(4):240-245.
- ↑ Lee BW, Murakami Y, Duncan MT, et al. Patient-related and system-related barriers to glaucoma follow-up in a county hospital population. Invest Ophthalmol Vis Sci. 2013;54(10):6542-6548.
- ↑ 26.0 26.1 Moore DB, Hammer JD, Akhtari R, Beck J, Sanders S, Kryscio RJ. Squeeze Me if You Can: Variability in Force Requirements to Extract a Drop From Common Glaucoma Bottles. J Glaucoma. 2016;25(9):780-784.
- ↑ 27.0 27.1 Moore DB, Walton C, Moeller KL, Slabaugh MA, Mudumbai RC, Chen PP. Prevalence of self-reported early glaucoma eye drop bottle exhaustion and associated risk factors: a patient survey. BMC Ophthalmol. 2014;14:79.
- ↑ Hennessy AL, Katz J, Covert D, et al. A video study of drop instillation in both glaucoma and retina patients with visual impairment. Am J Ophthalmol. 2011;152(6):982-988.
- ↑ Hahn SR. Patient-centered communication to assess and enhance patient adherence to glaucoma medication. Ophthalmology. 2009;116(11 Suppl):S37-42.
- ↑ Mansukani SS. Improving adherence to drug-treatment regimens for glaucoma. Manag Care. 2002;11(11 Suppl):49-53.
- ↑ McDonald JE, Dickinson JK. A Novel Approach to Helping People with Glaucoma Use Their Drops Routinely. Optom Vis Sci. 2019;96(5):331-334.
- ↑ 32.0 32.1 Okeke CO, Quigley HA, Jampel HD, et al. Interventions improve poor adherence with once daily glaucoma medications in electronically monitored patients. Ophthalmology. 2009;116(12):2286-2293.
- ↑ Davis SA, Carpenter DM, Blalock SJ, et al. Glaucoma Patient Preferences for Video Education on Eye Drop Technique. Optom Vis Sci. 2019;96(5):325-330.
- ↑ Schneider KJ, Hollenhorst CN, Valicevic AN, et al. Impact of the Support, Educate, Empower Personalized Glaucoma Coaching Program Pilot Study on Eye Drop Instillation Technique and Self-Efficacy. Ophthalmol Glaucoma. 2021;4(1):42-50.
- ↑ Pizzi LT, Tran J, Shafa A, et al. Effectiveness and Cost of a Personalized Reminder Intervention to Improve Adherence to Glaucoma Care. Appl Health Econ Health Policy. 2016;14(2):229-240.
- ↑ Leshno A, Gaton D, Singer R, et al. A novel EyePhone(c) App for improving adherence to glaucoma therapy. Graefes Arch Clin Exp Ophthalmol. 2021;259(5):1253-1262.
- ↑ Aguilar-Rivera M, Erudaitius DT, Wu VM, et al. Smart Electronic Eyedrop Bottle for Unobtrusive Monitoring of Glaucoma Medication Adherence. Sensors (Basel). 2020;20(9).
- ↑ Sanchez FG, Mansberger SL, Kung Y, et al. Novel Eye Drop Delivery Aid Improves Outcomes and Satisfaction. Ophthalmol Glaucoma. 2021.
- ↑ Toteberg-Harms M, Meier-Gibbons F. Is laser trabeculoplasty the new star in glaucoma treatment? Curr Opin Ophthalmol. 2021;32(2):141-147.
- ↑ Realini T, Gazzard G, Latina M, Kass M. Low-energy Selective Laser Trabeculoplasty Repeated Annually: Rationale for the COAST Trial. J Glaucoma. 2021;30(7):545-551.