Systemic Medications and Glaucoma Patients⁎

Systemic Medications and Glaucoma Patients* Dear Editor: Given the age of typical glaucoma patients, they are likely to have comorbid diseases such as cardiovascular disorders and hyperlipidemia, and be prescribed pharmacotherapy for these diseases. We recently described potential problems with compliance associated with the addition of a second glaucoma medication.1 Adherence to therapy is inversely related to the complexity of therapy.2 To evaluate whether the number of prescribed systemic medications may in part contribute to this observation, we evaluated the total burden of prescribed systemic medications facing relatively healthy glaucoma patients on multiple intraocular pressure (IOP)– lowering medications. This observation has not been described previously. We evaluated the database of a double-masked, randomized, active-controlled, 3-month efficacy and safety trial comparing a travoprost/timolol fixed combination with travoprost or timolol.3 We tabulated the chronic systemic prescription medications and, based upon the labeled indication and dosing regimen, assessed the most common systemic diseases, and calculated the number of prescriptions per patient and doses per day for chronic systemic prescription treatments. We analyzed 263 subjects. The mean (⫾ standard deviation) age was 62.9⫾11.2 years (range, 31–91), 51% were female, and 49% (130/263) were ⱖ65 years of age. Seventy-five percent of patients (198/263) reported using nonglaucoma systemic medications. Proportions (numbers) of patients reporting use of 1, 2, 3, 4, 5, or ⱖ6 medications were 16% (41), 19% (50), 16% (42), 9% (23), 6% (17), and 10% (25), respectively. The most common comorbid diseases being treated were systemic cardiovascular disorders (49% [129/263]), followed by hyperlipidemia (28% [74/263]; Table 1 [available at http://aaojournal.org]). The mean number of prescriptions per patient for each disease ranged from 1.0 to 1.7, with the maximum per patient ranging up to 4. The mean number of prescriptions per patient was higher in those 65 years or older (2.83; 368 prescriptions in 130 patients) than in those younger (1.86; 247 prescriptions in 133 patients) and higher in females (2.52; 340 prescriptions in 135 patients) than in males (2.16; 275 prescriptions in 127 patients). The mean number of doses per day per patient was 2.8⫾2.8 (range, 0 –15; median, 2). Although not tabulated, many subjects were also taking acute and chronic over-the-counter therapies such as aspirin, vitamins, calcium supplements, and proton pump inhibitors. *Presented at: American Glaucoma Society meeting, March, 2005; Snowbird, Utah. Study sponsored by Alcon Laboratories, Inc., Fort Worth, Texas. Drs Robin and Novack are consultants to and Mr Covert is an employee of and stockholder in Alcon Laboratories, Inc. Dr Robin is also a consultant to Pfizer and Merck.

The finding that older patients with glaucoma frequently require multiple systemic medications is not surprising. We found that 25% of patients required ⱖ4 medications with multiple doses per day. As clinical studies typically enroll subjects who are relatively healthy, the number of chronic systemic prescriptions used by glaucoma patients may actually be higher. The relative good health and young age of this population could explain the relative absence of cardiovascular disease. We do not know whether the requirement for systemic medications is greater for glaucoma patients than other age-, gender-, and race-matched subjects. However, this is the first time that the systemic medication profile of glaucoma patients requiring multiple IOP-lowering medications has been quantified. Systemic medications may affect a patient’s adherence to therapy because of cost and complexity of therapy. Furthermore, in those patients with medical insurance, even minimal copayments can add up to a significant dollar amount for the patient with limited income. Although patients with acute symptomatic diseases are most sensitive to the level of copayment, even patients with chronic asymptomatic diseases are influenced by these fees.4 Ophthalmologists should be aware of the total prescribed medication burden of the patient when considering glaucoma therapeutic choices for their patients. Poor compliance has been associated with higher IOPs and greater visual field loss.5 DAVID COVERT, MBA Fort Worth, Texas ALAN L. ROBIN, MD Baltimore, Maryland GARY D. NOVACK, PHD San Rafael, California References 1. Robin AL, Covert D. Does adjunctive glaucoma therapy affect adherence to the initial primary therapy? Ophthalmology 2005;112:863– 8. 2. Blackwell B. Treatment adherence. Br J Psychiatry 1976;129: 513–31. 3. Barnebey HS, Orengo-Nania S, Flowers BE, et al. The safety and efficacy of travoprost 0.004%/timolol 0.5% fixed combination ophthalmic solution. Am J Ophthalmol 2005;126:1–7. 4. Goldman DP, Joyce GF, Escarce JJ, et al. Pharmacy benefits and the use of drugs by the chronically ill. JAMA 2004;291: 2344 –50. 5. Stewart WC, Chorak RP, Hunt HH, Sethuraman G. Factors associated with visual loss in patients with advanced glaucomatous changes in the optic nerve head. Am J Ophthalmol 1993;116:176 – 81.

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Ophthalmology Volume 112, Number 10, October 2005 Table 1. Prescriptions by Therapeutic Area Measure

Cardiovascular Disorders

Hyperlipidemia

Diabetes

Estrogen Replacement

Arthritis

Depression

No. of patients with prescriptions Percent of 263 patients No. of prescriptions Mean prescriptions per patient Maximum prescriptions per patient

129 49 210 1.6 4

74 28 78 1.1 2

59 22 103 1.7 3

33 13 33 1.0 1

29 11 30 1.0 2

21 8 22 1.0 2

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