Cost-Effectiveness of Treatment for Threshold Retinopathy of Prematurity Gary C. Brown, MD, MBA*‡; Melissa M. Brown, MN, MD, MBA*§; Sanjay Sharma, MD, MSc(Epid)*; William Tasman, MD‡; and Heidi C. Brown* ABSTRACT. Objective. Retinopathy of prematurity (ROP) is a leading cause of adverse visual outcomes in premature infants. Both laser photocoagulation and cryo- therapy have been demonstrated in clinical trials to be efficacious in reducing the incidence of visual loss occur- ring secondary to threshold ROP. Visual data recently have become available concerning the long-term clinical efficacy of both treatments, as have data concerning the utility value of visual states in general. Accordingly, we undertook an analysis to ascertain the cost-effectiveness of laser photocoagulation and cryotherapy in the treat- ment of threshold ROP. Design. A computer simulation economic model is presented to evaluate the cost-effectiveness of cryother- apy and laser photocoagulation therapy, compared with the natural course of the disease, for treating premature infants with threshold ROP. The model applies long- term visual data from previous clinical trials, utility anal- ysis, decision analysis, and economic principles, such as present value analysis, to account for the time value of money to arrive at a cost per quality-adjusted life-year (QALY) gained. Outcome Measures. Cost per QALY gained from laser therapy and cryotherapy. Results. Laser photocoagulation therapy for thresh- old ROP costs $678 1998 US dollars (at a 3% discount rate to account for the time value of money) for each QALY gained from treatment. Cryotherapy for the same disease costs $1801 per QALY at a similar discount rate. Conclusions. From the point of view of cost-effective- ness, laser therapy seems to have an advantage over cryotherapy for the treatment of threshold ROP. Pediatrics 1999;104(4). URL: http://www.pediatrics.org/ cgi/content/full/104/4/e47; threshold retinopathy of pre- maturity, laser therapy, cryotherapy, cost-effectiveness. ABBREVIATIONS. ROP, retinopathy of prematurity; HCFA, Health Care Financing Agency; CPT, Current Procedural Termi- nology; QALY, quality-adjusted life year; $/QALY, cost per qual- ity-adjusted life-year. R etinopathy of prematurity (ROP) is the leading cause of blindness among premature infants. 1 It occurs in some form in 32% of infants with birth weights 1000 g. 1 Among those infants with birth weights 1251 g, 7% to 8% will develop thresh- old ROP. 2 Threshold ROP is defined as proliferative retinal vascular disease that is located in zone 1 or 2 in conjunction with plus disease and associated with 5 contiguous or 8 cumulative clock hours of extrareti- nal neovascularization. 1 Of those who are treated for threshold disease, the long-term survival is 88%. 3 The Multicenter Trial of Cryotherapy for ROP ini- tially demonstrated that retinal cryotherapy for threshold ROP decreased the incidence of an unfa- vorable anatomic outcome from 51% to 31%. 2 Subse- quently, the Laser ROP Study Group 4 showed with a meta-analysis that the risk of an unfavorable out- come in eyes with threshold ROP was 19% with cryotherapy and 8% with laser therapy. Now that children who were treated for threshold ROP are maturing, data concerning the long-term visual acuity results from prospective clinical trials are available. 5–7 It seems that the mean visual acuity in eyes treated for threshold ROP may be better in those children treated with laser photocoagulation than in those treated with cryotherapy. Although systemic complications can be associated with cryo- therapy 8 and laser therapy, 9 the incidence of such complications seems to be low. Cost-effective analyses that involve utility theory are being reported with increasing frequency. 10 –13 Utility analysis incorporates patient-based prefer- ences that allow the quality of life associated with a health (disease) state to be quantified. In view of recent data concerning utility values in patients with visual loss 14 and new information on visual results after therapy for ROP, 5–7 we undertook an analysis of the cost-effectiveness of laser photocoagulation and cryotherapy for the treatment of threshold ROP. METHODS Overview Software produced by Treeage, Inc (Williamstown, MA) 15 was used to perform decision analysis to simulate the clinical situation involving laser therapy, cryotherapy, and no therapy for patients with threshold ROP. This microcomputer model takes into ac- count the mortality within this group of patients, as well as the treatment results expressed in utility form. The numbers of uni- lateral and bilateral cases also were factored into the analysis. Utility values were used at the terminal nodes at the right side of the decision tree to provide the most probable utility value out- comes given the different possible clinical scenarios. The utility From the *Center for Evidence-Based Healthcare, Flourtown, Pennsylvania; the ‡Retina Service and the §Cataract and Primary Eye Care Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania; and the Epidemiology Unit, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts. Received for publication Dec 31, 1998; accepted Apr 26, 1999. Reprint requests to (G.C.B.) Center for Evidence-Based Healthcare, Suite 210, 1107 Bethlehem Pike, Flourtown, PA 19031. E-mail: gary0514@aol.com PEDIATRICS (ISSN 0031 4005). Copyright © 1999 by the American Acad- emy of Pediatrics. http://www.pediatrics.org/cgi/content/full/104/4/e47 PEDIATRICS Vol. 104 No. 4 October 1999 1 of 6 by guest on August 8, 2015 pediatrics.aappublications.org Downloaded from