Update on photodynamic therapy.

To date, photodynamic therapy with verteporfin has been shown to benefit those patients with age-related molecular degeneration and choroidal neovascularization that is subfoveal and predominately classic (> 50%). As of this writing, the Food and Drug Administration is requiring additional data before verteporfin is approved for treatment of occult subfoveal choroidal neovascularization. Photodynamic therapy has also proved beneficial for subfoveal lesions secondary to high myopia. Although there is potential for patients with angioid streaks, ocular histoplasmosis syndrome, and idiopathic causes of choroidal neovascularization to benefit from photodynamic therapy, randomized clinical trials have not been performed. Photodynamic therapy has not been shown to benefit patients with minimally classic (< 50%) lesions.

Health care economic analyses and value-based medicine.

Health care economic analyses are becoming increasingly important in the evaluation of health care interventions, including many within ophthalmology. Encompassed with the realm of health care economic studies are cost-benefit analysis, cost-effectiveness analysis, cost-minimization analysis, and cost-utility analysis. Cost-utility analysis is the most sophisticated form of economic analysis and typically incorporates utility values. Utility values measure the preference for a health state and range from 0.0 (death) to 1.0 (perfect health). When the change in utility measures conferred by a health care intervention is multiplied by the duration of the benefit, the number of quality-adjusted life-years (QALYs) gained from the intervention is ascertained. This methodology incorporates both the improvement in quality of life and/or length of life, or the value, occurring as a result of the intervention. This improvement in value can then be amalgamated with discounted costs to yield expenditures per quality-adjusted life-year ($/QALY) gained. $/QALY gained is a measure that allows a comparison of the patient-perceived value of virtually all health care interventions for the dollars expended. A review of the literature on health care economic analyses, with particular emphasis on cost-utility analysis, is included in the present review. It is anticipated that cost-utility analysis will play a major role in health care within the coming decade.

Patient, community and clinician perceptions of the quality of life associated with diabetes mellitus.

BACKGROUND: A study was undertaken to assess the quality of life of patients with type 1 and type 2 diabetes mellitus and to ascertain whether clinicians and non-diabetic respondents from the general public have similar views of the impact of diabetes upon health-related quality of life. MATERIAL/METHODS: Time tradeoff utility values were generated from a standardized time-tradeoff questionnaire. Three hundred and fifty-two individuals with type 1 or type 2 diabetes mellitus, 157 non-diabetic participants from the general public (community), and 61 health care clinicians participated in the study. RESULTS: The mean utility score for diabetic patients was 0.889 and the median utility score was 1.000. The mean utility score for clinicians was 0.861, with a median value of 0.894, while the respective mean and median scores for the general public were 0.919 and 0.953. There was a significant difference between the distribution of the means of scores of clinicians and patients as well as between clinicians and the general public. There was no significant difference between the utility scores of patients and the general public. Within the group of diabetic patients, there was no significant difference in utility scores between type 1 and type 2 diabetics. CONCLUSIONS: Clinicians tended to overemphasize the impact that diabetes mellitus has on health related quality of life, while the non-diabetic publics' utility values are more closely correlated with those of diabetics themselves. We conclude that there is a significant difference in how clinicians, diabetics and the general public perceive the effect diabetes has upon quality of life.

Quality of life with visual acuity loss from diabetic retinopathy and age-related macular degeneration.

OBJECTIVE: To compare the quality of life in patients with visual acuity loss occurring secondary to diabetic retinopathy with visual acuity loss occurring secondary to age-related macular degeneration (ARMD). METHODS: Consecutive patients with diabetic retinopathy and ARMD were evaluated using the time trade-off method of utility value analysis. Both groups were stratified according to the degree of visual acuity loss in the better-seeing eye (group 1: 20/20-20/25, group 2: 20/30-20/40, group 3: 20/50-20/100, group 4: < or =20/200). Utility values obtained from the patients, once stratified for visual acuity group, were compared with use of the t test and the Mann-Whitney U test. In addition, a 2-way analysis of variance was performed to control for potential confounding variables. RESULTS: No difference was found between the utility value means of the diabetic retinopathy (n = 333) and ARMD (n = 246) subgroups stratified according to visual acuity levels: group 1, P =.54; group 2, P =.96; group 3, P =.09; and group 4, P =.32. A 2-way analysis of variance demonstrated that, among the variables of ocular disease, sex, age, and visual acuity in the better-seeing eye, only visual acuity was significantly associated with utility values (P =.003). CONCLUSIONS: At similar levels of visual acuity loss, that associated with diabetic retinopathy causes a similar reduction in quality of life to that associated with ARMD. This information has important implications for use in cost-utility analyses of ophthalmic interventions.

A cost-utility analysis of interventions for severe proliferative vitreoretinopathy.

PURPOSE: The purpose of this study was to report a reference case, patient preference-based, incremental, cost-utility analysis for treatments of retinal detachment associated with severe proliferative vitreoretinopathy (PVR). DESIGN: Computer-based economic model utilizing data from the Medicare health insurance system in the United States. METHODS: A cost-utility analysis compared vitreoretinal surgery using expanding gases and silicone oil therapy to the natural course of retinal detachment associated with severe PVR. The model applies long-term published visual data from the Silicone Study Group, time tradeoff utility analysis, decision analysis with Markov modeling, and discounting of costs and health benefits as per the Panel on Cost-Effectiveness in Health and Medicine. The major outcome measure was in year 2000 United States dollars per quality-adjusted life-year (dollars/QALY) gained. RESULTS: Vitreoretinal surgery for retinal detachment complicated by severe PVR, as compared with no treatment, resulted in a mean gain of 0.128-0.200 discounted (3% annual rate) quality-adjusted life-years per treated patient. Silicone oil (dollars/QALY gained of 40,252 dollars) was slightly more cost-effective than perfluoropropane (C(3)F(8)) gas (dollars/QALY gained of 46,926 dollars) in eyes with PVR without previous vitrectomy, whereas C(3)F(8) gas (dollars/QALY gained of 46,162 dollars) was more cost-effective than silicone oil (dollars/QALY gained of 62,383 dollars) with previous vitrectomy and PVR. Sensitivity analysis resulted in a dollars/QALY gained of 13,347 dollars when 10% of opposite eyes had a severe visual loss to 202,128 dollars when a discount rate of 10% was utilized and opposite eyes initially had good vision. CONCLUSIONS: The incremental expense of interventions for retinal detachment associated with PVR is cost-effective when compared with other widely accepted interventional therapies across diverse medical specialties.

Quality of life and systemic comorbidities in patients with ophthalmic disease.

AIM: To ascertain the effect of serious systemic comorbidities upon the quality of life of patients with ophthalmic diseases. METHODS: Time tradeoff utility values were obtained in consecutive ophthalmic patients who presented with ocular disease. Multivariate analysis was undertaken to evaluate whether the systemic comorbidities of diabetes mellitus, heart disease, cancer, cerebrovascular accident, and/or renal failure requiring dialysis influenced ocular utility values. RESULTS: Among the 390 patients with ocular diseases studied, 250 had the systemic comorbidities of diabetes mellitus, heart disease, cancer, stroke, and/or renal failure requiring dialysis, while 140 lacked these comorbidities. There was no statistically significant difference (p = 0.091) between the comorbidity and no comorbidity groups in self assessed quality of life as measured by ocular utility values after taking into account potentially confounding variables. CONCLUSIONS: In patients with ocular disease, ocular utility values related to the visual loss do not appear to be affected by the presence of select, concomitant, serious systemic diseases. Thus, visual loss seems to cause a similar diminution in self assessed quality of life in those who do and do not have serious associated systemic comorbidities. This information has important implications for the calculation of cost effective analyses.