Supplements Managed Care Issues in Glaucoma: Emerging Trends and Treatment
The Prevalence of Glaucomatous Risk Factors in Patients From a Managed Care Setting: A Pilot Evaluation
Notwithstanding these limitations, this study provides further insight into the prevalence and nature of glaucomatous RFs in an urban managed care population. The retrospective review of medical records revealed that known demographic, clinical, and ocular RFs for glaucomatous progression were present in up to approximately one third of patients treated for ICD-9 glaucoma-related diagnoses. Although the results of the statistical analyses confirmed the predictive value of these RFs, it is evident that existing models for determining the risk of glaucomatous progression may not account for several important RFs. Three of the 5 most prevalent RFs in this sample, namely systemic hypertension, positive family history, and Latino ancestry, were not included in the OHTS risk scoring system. These RFs did not enhance the explanatory power of the OHTS model; however, ascertainment of these factors was based on patient history without confirmation of chart review or direct testing.4 Additionally, a number of RFs described as predictive in other studies, such as exfoliation syndrome and pigment dispersion,25,30-32 were not evaluated in the OHTS model because of the small numbers of affected patients. The percentages of missing data in our analyses suggested that current predictive models might also rely on certain ocular indices, such as PSD or CCT, which may not be routinely or practically measured in clinical practice.
Finally, but foremost, for a risk scoring system to be clinically useful, clinicians must be educated on interpreting the results and offered guidance on how to use the information optimally in making treatment decisions. For example, using various methods, several studies evaluating the long-term outcomes of treated and untreated patients have generated data suggesting a clinically relevant threshold value (ie, the risk above which the expected benefits of treatment outweigh the possible risks) for the risk of conversion from OHT to glaucoma and/or to blindness or disability.2,3,33-36 Although one study estimated that between 12 and 83 patients with OHT will require treatment to prevent 1 patient from progressing to unilateral blindness over a 15-year period,33 this information may be less useful for the practitioner who must prospectively render decisions for the individual patient on a daily basis. Thus, future studies should aim to develop predictive models incorporating these considerations and tailor existing models for greater ease and practicality of use and interpretation in the clinical setting.
Laurie Kozbelt assisted in the preparation of this manuscript.
Author Affiliations: From Southern California Kaiser Permanente Medical Group, Los Angeles Medical Center, Los Angeles, CA; Jules Stein Eye Institute, University of California, Los Angeles, CA; Allergan, Inc., Irvine, CA; Marinus Consulting, LLC, Mountain View, CA.
Author Disclosures: This project was previously presented in part as a poster at the annual meeting of the Association for Research in Vision and Ophthalmology, Fort Lauderdale, FL, May 2007, and at the annual meeting of the International Society of Pharmacoeconomics and Outcomes Research, Arlington, VA, May 2007. The authors (ENF, SKL) received honoraria from Allergan, Inc; the authors (JGW, THC) are employed by Allergan, Inc; the author (ENW) is a consultant to Allergan, Inc.
Funding Source: The research and manuscript were funded by Allergan, Inc.
Authorship Information: Concept and design (ENF, SKL, JGW, THC, ENW); acquisition of data (ENF, SKL, JGW, THC, ENW); analysis and interpretation of data (ENF, SKL, JGW, THC, ENW); drafting of the manuscript (ENW); critical revision of the manuscript for important intellectual content (ENF, SKL, JGW, THC, ENW); statistical analysis (ENF, SKL, JGW, THC, ENW); and supervision (ENF, SKL).
Address Correspondence to: Ervin N. Fang, MD, Southern California Kaiser Permanente Medical Group, 1515 N Vermont Ave, 7A, Los Angeles, CA 90027. E-mail: Ervin.n.Fang@KP.org.
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