Clinical Outcomes of Glaucoma Treatments Over a Patient Lifetime

Medical Costs of and Changes in Glaucoma Treatment among Patients Newly Starting Glaucoma Care

Purpose: To use a medical claim database to investigate medical costs and treatment patterns among patients newly starting glaucoma care.Subjects and methods: Subjects registered in the Japan Medical Database Center (JMDC) from January 2005 to March 2016 who were newly diagnosed with glaucoma, started glaucoma treatment, and had treatment records covering more than five years were included in the analysis. All direct medical costs were collected for a period of up to ten years. Factors affecting medical costs were analyzed. Changes in hypotensive eyedrops and choices related to glaucoma surgery were also analyzed.Results: Out of approximately 1.42 million subjects, 2,393 satisfied the inclusion and exclusion criteria. The average total medical cost incurred per patient over a period of ten years was US$9,030, including US$1,214 during the initial year. The proportion of the total cost represented by the cost of hypotensive eyedrops increased from 5.2% to 10.6% over the ten-year period. Medical costs were higher in patients younger than ten years old than in patients of all other age groups. The number of ocular hypotensive eyedrops increased from 0.9 to 1.5 over the ten-year period. Medical costs were higher for subjects with secondary glaucoma than for other subjects. Sixty-three patients underwent trabeculotomy or trabeculectomy, and trabeculectomy was the preferred choice in later years.Conclusions: The total direct medical cost associated with glaucoma was US$9,030 for the first ten years. Drug costs gradually increased with treatment duration and patient age and varied by glaucoma type.

[The role of fixed dose combinations in the treatment of primary open-angle glaucoma]

A great number of patients with primary open-angle glaucoma require combination therapy with several hypotensive drugs of different pharmacological groups to efficiently compensate the intraocular pressure (IOP) and prevent further development of glaucoma. Although glaucoma treatment usually starts with monotherapy, several preparations administered simultaneously have stronger hypotensive effect further increased by their additive action. However, the increased frequency of instillations may lead to drug washout and decreased patient compliance. Fixed dose combinations (FDCs) are a pharmacological form of eye drops that combines two or more active drugs in a single dosage form. The frequency of FDCs administration does not exceed two per day, which is convenient for long-term application and helps improve patient compliance. FDCs tolerability tends to be higher than that of simultaneous instillations of separate monotherapy drugs, while the hypotensive in clinical trials is comparable, in some real practice trials is superior. A review of existing studies showed that FDCs are superior to monotherapy in terms of cost-effectiveness. The use of FDCs was found to be beneficial for glaucoma treatment from the viewpoints of both reaching the target IOP for preserving visual functions in glaucoma patients, and minimizing the long-term treatment costs.

Effect of quantitative intraocular pressure reduction on visual field defect progression in normal tension glaucoma under medical therapy applying Markov model

Purpose

To quantitatively evaluate the association of intraocular pressure (IOP) reduction with visual field defect (VFD) progression in normal tension glaucoma (NTG) under medical therapy.

Patients and methods

Clinical data for 622 eyes of 311 primary open-angle glaucoma and NTG patients were collected from April 2006 to March 2016. Of these patients, those with normal IOP, glaucomatous VFD by Anderson’s criteria, corrected visual acuity ≥0.7, >5 years of medical therapy, ≥5 visual field tests at least five times at 12-month intervals, visual field testing reliability coefficients of ≤33%, and mean deviation (MD) exceeding below −20 dB in the initial visual field test were included in this retrospective data analysis. MD and IOP data were collected at baseline and after 5 years. Following MD categorization into stages I to IV, stage transition matrices were generated using a Markov model to evaluate VFD changes. Eyes were divided based on IOP reduction (0%, 10%, 15%, 20%, 25%, 30%) from baseline. VFD aggravations were compared using the Markov model and MD slopes with IOP reduction rates as cutoff values.

Results

Overall, 132 eyes of 132 NTG patients fulfilled the eligibility criteria. MD decreased significantly (P<0.0001) at 5 years vs baseline. During follow-up, visual field stage using the Markov model was constant in ~60%, with transitions in ~40%. IOP decreased significantly (P>0.001) at 5 years vs baseline. Though MD slopes did not differ significantly between each of the groups that achieved the various IOP reduction cut-off values and the corresponding group that did not achieve the cut-off values, a significant difference (P=0.0432) in VFD was found between the group that achieved the 25% cut-off value and the group that did not when evaluated using the Markov model.

Conclusion

In NTG patients, VFD aggravation was significantly suppressed in groups with IOP reductions of ≥25% from baseline.

Treatment Carryover Impacts on Effectiveness of Intraocular Pressure Lowering Agents, Estimated by a Discrete Event Simulation Model

Purpose

To compare the effectiveness of two treatment sequences, latanoprost–latanoprost timolol fixed combination (L-LT) versus travoprost–travoprost timolol fixed combination (T-TT), in the treatment of open-angle glaucoma (OAG) or ocular hypertension (OHT).

Methods

A discrete event simulation (DES) model was constructed. Patients with either OAG or OHT were treated first-line with a prostaglandin, either latanoprost or travoprost. In case of treatment failure, patients were switched to the specific prostaglandin-timolol sequence LT or TT. Failure was defined as intraocular pressure higher than or equal to 18 mmHg at two visits. Time to failure was estimated from two randomized clinical trials. Log-rank tests were computed. Linear functions after log-log transformation were used to model time to failure. The time horizon of the model was 60 months. Outcomes included treatment failure and disease progression. Sensitivity analyses were performed.

Results

Latanoprost treatment resulted in more treatment failures than travoprost (p<0.01), and LT more than TT (p<0.01). At 60 months, the probability of starting a third treatment line was 39.2% with L-LT versus 29.9% with T-TT. On average, L-LT patients developed 0.55 new visual field defects versus 0.48 for T-TT patients. The probability of no disease progression at 60 months was 61.4% with L-LT and 65.5% with T-TT.

Conclusions

Based on randomized clinical trial results and using a DES model, the T-TT sequence was more effective at avoiding starting a third line treatment than the L-LT sequence. T-TT treated patients developed less glaucoma progression.

Glaucoma costs in Denmark in treatment naive patients

PURPOSE

To describe the costs and providers of glaucoma treatment in Denmark.

METHODS

Analyses were based on National Register data. Glaucoma/OHT patients were identified by their first prescription for glaucoma medication (ATC-codes) in the Danish Register of Medicinal Product Statistics 2002-2007. Patients had used no glaucoma medication for 6 months. Data for 2007 were sampled cross-sectionally for a budgetary analysis of glaucoma (ICD10 code) medication and services consumed in the primary and secondary health care services. Patients were categorized according to their number of treatment changes.

RESULTS

The Danish annual incidence rate of glaucoma was estimated at 1.2 per 1000 adult persons. Thirty-seven per cent of patients (men 44%, mean age 68 years; women 56%, mean age 71 years) persisted with their initial treatment regimen, 21% had changed to a second regimen, and 43% had experienced ≥ 3 regimens. Treatment costs increased with the number of sequential regimens. Annual glaucoma costs (health care sector perspective) were €305 for patients under their initial regimen, increasing to €740 with ≥ 3 regimens. Drug costs accounted for 57% of total cost.

CONCLUSIONS

Drugs represented the major cost of glaucoma, and those costs increased, obviously, with the number of treatment changes.

Contribution of modeling approaches and virtual populations in transposing the results of clinical trials into real life and in enlightening public health decisions

Modeling consists in aggregating separate pieces of knowledge, according to a given structure and rules. It allows studying the behavior of more or less complex systems by simulation techniques. Modeling is used in different state-of-the-art technological domains (meteorology, aeronautics). Its use has grown for the evaluation of medicines and medical devices, from conception to prescription (marketing authorization, reimbursement, price setting and re-registrations). It follows a scientific approach and is the object of good practice recommendations. Coupling models to virtual populations allows obtaining realistic results at the population level, testing diagnostic or therapeutic strategies, as well as estimating the consequences of transposing the results of clinical trials to the population. Through examples, the participants of the Round Table analyzed the contributions of the coupling of models and realistic virtual populations, and proposed guidelines for their judicious and systematic use.

Developing an algorithm to convert routine measures of vision into utility values for glaucoma

PURPOSE

Measures of quality of life called utility values (UVs) are needed to deliver the most cost-effective health care for glaucoma patients. UVs are rarely measured in clinical research and practice whereas clinical outcomes such as visual field are routinely collected. The aim of this study was to develop an algorithm that calculates UVs directly from combinations of routine measures of binocular visual field, visual acuity, and contrast sensitivity.

METHODS

A total of 132 outpatients with primary open angle glaucoma were recruited. The Time Trade-off (TTO) question was administered during face-to-face interviews. Binocular ETDRS logMAR visual acuity (VA(B)), binocular Pelli-Robson contrast sensitivity (CS(B)), and Humphrey 24-2 monocular visual field tests were performed on the same day. Integrated (binocular) visual field (IVF) scores were derived. Tobit regression analyses were used to model utility values based on combinations of IVF, VA(B), CS(B) and other controlling factors.

RESULTS

UVs recorded for 123 cases correlated significantly with both clinical measures of binocular visual function (r = -0.47, IVF; r = -0.48, VA(B); r = 0.50, CS(B); P <0.0001) and measures of vision-specific quality of life (r = 0.54-0.6, P <0.0001). Two final models incorporate terms for IVF and VA(B), with or without living arrangements, and explain 22% and 31% of variation in utilities. CS(B) was not included in either model due to co-linearity between CS(B) and VA(B) confounding the models.

CONCLUSION

The models provide preliminary algorithms for predicting the expected UVs for glaucoma populations directly from clinical outcomes collected routinely in clinical practice.

Role of fixed combinations in the management of open-angle glaucoma

The first-line option for lowering intraocular pressure (IOP) is a single hypotensive agent, but patients frequently require additional IOP-lowering agents to reach their target pressures. Disadvantages of this multi-therapy approach include washout effect, inconvenience and poor adherence. Fixed combinations (FCs) combine two or more hypotensive agents in a single bottle, providing a convenient once-daily therapy, which tends to improve adherence. FCs generally offer equivalent efficacy to concomitant use of the individual components, with equivalent or superior tolerability. Studies also show that FCs can be more cost effective than nonfixed combinations. In terms of optimizing IOP control, minimizing visual field deterioration, preventing visual disability and minimizing associated healthcare costs, FCs are an important component of glaucoma management.

Modelling the lifetime economic consequences of glaucoma in France

OBJECTIVE

To estimate the lifetime economic consequences of glaucoma in France.

METHODS

A Markov model estimated the average discounted outcome and cost of glaucoma treatment over a patient's lifetime. Clinical states were defined as first- to fourth-line drugs, no treatment, laser therapy, surgery, blindness and death. After each failure (always after the fourth-line drug) patients could receive either laser treatment or surgery followed by no treatment, or a new treatment. A societal perspective was adopted. Sensitivity analyses were performed.

RESULTS

Discounted medical costs were euro 7,322 for ocular hypertension treatment (OHT) and euro 8,488 for a glaucoma patient. Social costs of OHT and glaucoma patients exceeded medical costs. First-line use of the most effective drug would reduce medical and social costs. Societal willingness to pay for the vision benefit would equal the medical costs. Treatment initiated with the most effective drug is a cost saving strategy.

CONCLUSIONS

Public health decisions in glaucoma treatment should take a broad economic view embracing the lifetime duration of the disease. There is still a place both within and outside the healthcare system for therapeutic innovations with important economic consequences that bring high added value to patients.

Cost of illness of glaucoma: a critical and systematic review

Cost-of-illness studies determine the total financial burden of a disease by considering direct and indirect costs, including medication, diagnostics and surgery. Studies of resource use and costs associated with primary open-angle glaucoma have used varying methodologies. Most have focused on consumption of healthcare resources at various stages of disease to anticipate costs. The direct costs associated with the disease often continue to increase as glaucoma progresses from the earliest to most advanced stages. Determinations of the costs associated with glaucoma progression and prevention should also incorporate the chance of patient non-compliance with treatment. Since glaucoma severity most often correlates with increased costs, minimizing or halting visual field loss and increasing patient treatment compliance may all contribute to a reduction in the overall economic burden of glaucoma.

Assessment of the cost effectiveness of travoprost versus latanoprost as single agents for treatment of glaucoma in France

BACKGROUND AND OBJECTIVE

Control of intraocular pressure (IOP) is a major factor in avoiding visual impairment related to glaucoma. Both the cost and the effectiveness of therapy should be considered when initiating this lifelong treatment. The aim of this study was to assess the cost effectiveness of travoprost versus latanoprost as single agents for the treatment of glaucoma in France.

METHODS

Two surveys, one documenting efficacy and the other costs, were used to provide data for a Markov model. The model reproduced the 5-year course of patients receiving a prostaglandin analogue, travoprost or latanoprost, as monotherapy. The effectiveness criterion was fitted with a Weibull distribution from a national study. Transition probabilities and costs per treatment line were extracted from two French observational databases. Bootstrap techniques were implemented to drive the probabilistic sensitivity analyses. The study compared both treatments given once daily as monotherapy to ambulatory patients with primary open-angle glaucoma or ocular hypertension. The main outcome measure was mean time to treatment change (MTTC). Possible treatment changes were the addition of adjunctive medication, treatment substitution, laser therapy or surgery. After laser therapy or surgery, patients could continue with no treatment or proceed to prostaglandin analogue as monotherapy or treatment substitution. IOP was stratified at treatment onset as < or =20, 21-23 and > or =24 mmHg, respectively. All costs were expressed in 2005 euros.

RESULTS

MTTC was 44.3 months for travoprost and 37.8 for latanoprost. Additional 5-year costs for travoprost were euro51, resulting in an incremental cost-effectiveness ratio without treatment change of euro95 per year. Of patients treated with latanoprost, 1.9% underwent laser therapy or surgery, compared with 1.2% of patients treated with travoprost. The results differed with baseline IOP values, such that 55.6%, 53.9% and 50.4% of patients with pretreatment IOP values of < or =20, 21-23 and > or =24 mmHg, respectively, continued to receive travoprost treatment at 5 years, compared with 32.3%, 26.1% and 26.1% of patients, respectively, receiving latanoprost. Thus, incremental cost-effectiveness ratios (ICERs) without treatment change were euro140, euro45 and euro123 per year, respectively.

CONCLUSION

Travoprost demonstrated a longer effectiveness profile than latanoprost and minimized early treatment changes. The smaller proportion of patients needing a new treatment, laser therapy or surgery virtually compensated for the higher travoprost acquisition cost. Overall, travoprost is cost effective compared with latanoprost, and is most cost effective in patients with pretreatment IOPs between 21 and 23 mmHg.

Cost-effectiveness of latanoprost and timolol maleate for the treatment of glaucoma in Scandinavia and the United Kingdom, using a decision-analytic health economic model

PURPOSE

To assess the cost-effectiveness of latanoprost or timolol in glaucoma treatment in Norway, Sweden, Denmark (Scandinavia) and the United Kingdom (UK).

METHODS

A Markov model was constructed to perform a cost-effectiveness analysis. Health states were 'stable' and 'progressed' glaucoma, and transition probabilities for both primary open-angle and exfoliation glaucoma were derived from the medical literature. Practice patterns were obtained from surveys completed by 54 ophthalmologists geographically dispersed throughout each country. Country specific unit costs were used for medications, patient visits, diagnostics, and therapeutic procedures.

RESULTS

Over the life of the model latanoprost was less expensive than timolol by 5.3-7.6% (Scandinavia) and 2.1% (UK). Following adjustments, therapy in the original timolol-treated cohort was slightly more effective in each country with a difference in 0.003-0.015 years to progression of glaucoma existing between latanoprost. This may have resulted from the model design, which reflected that physicians ultimately control most patients' glaucoma over 5 years by adding or changing therapy. The associated incremental cost-effectiveness ratios for latanoprost vs timolol generated by the Scandinavian and the UK models, respectively, were: Norway 351,396 NOK; Sweden 988,985 SEK; Denmark 351,641; and the UK 4751 GBP.

CONCLUSIONS

Over 5 years, in the UK timolol is the cost-effective option, whereas in Scandinavia latanoprost may be the cost-effective alternative to timolol.

Failure of medical therapy despite normal intraocular pressure

The disease glaucoma is now defined by characteristic optic disc and visual field change, without specific reference to the intraocular pressure (IOP). Success of treatment is no longer judged by the mere attainment of IOP less than 21 mmHg. Controversy remains, however, in deciding appropriate management where optic disc and/or visual field damage continues to progress despite a 'normal' IOP having been achieved with medical treatment. A panel of international glaucoma experts has provided management recommendations in four clinical scenarios--open-angle glaucoma, open-angle glaucoma in a myopic contact lens wearer, uveitic glaucoma and open-angle glaucoma in combination with visually significant cataract--where optic nerve and visual field progression has continued despite an IOP less than 21 mmHg on full medical treatment. Surgical intervention with mitomycin trabeculectomy is the most favoured further therapy.

Comment s′assurer de la stabilité d′un glaucome ?

Visual field results are subject to fluctuations in glaucoma and it is important to evaluate them to differentiate fluctuation and progression. Three visual fields are thus required for the determination of progression because of these short or long term fluctuations. During each measurement, some points are tested twice in order to assess short term fluctuation. Other fluctuations are simply due to technical difficulties like a change of position of the head from one examination to the next one. Learning effect is in fact the more important factor which may improve results. However some real long term fluctuations exist, mainly as a function of the general health of the patient. Progression of the visual field is usually assessed by subjective analysis of the fields with an evaluation of the intensity and the size of scotomas and a comparison of global indices. A more objective analysis can be obtain by the use of specific programs like the "Glaucoma Progression Analysis" with the Humphrey Perimeter or the "Progressor" with the Octopus Perimeter.

Comparison of Diurnal Intraocular Pressure Control by Latanoprost versus Travoprost

BACKGROUND AND OBJECTIVE

Intraocular pressure (IOP) is known to be subject to daily fluctuations, the occurrence of which is a risk factor for progression of glaucoma. Control of IOP during the day by drugs is an important therapeutic target. We set out to compare the IOP control of travoprost and latanoprost taking into account the time since last instillation and the time of IOP measurement.

METHODS

This was a prospective, cross-sectional observational study with some retrospective data collection. Private ophthalmologists were selected to each recruit ten patients with primary open-angle glaucoma and/or ocular hypertension receiving either travoprost or latanoprost as monotherapy. Clinical endpoints included IOP measurements and percentage of patients attaining predefined target IOPs. Six patient subgroups were defined according to: (a) IOP measurement time: before 1200h, 1200h-1600h and after 1600h, and (b) time since last intake (<24 hours, >24 hours). Analyses comprised chi(2) and Wilcoxon tests, ANOVA, logistic regressions and adjustment by propensity score.

RESULTS

In total, 2052 patients treated with travoprost (n = 1704) or latanoprost (n = 348) participated in the study. Treatment groups were comparable at baseline, except for a longer treatment duration in latanoprost-treated patients. When the interval between the last treatment instillation and IOP measurement (treatment/IOP interval) was <24 hours (n = 1241), 82% of travoprost-treated patients attained pre-defined target IOP versus 67% with latanoprost (p < 0.0001). This difference was greatest after 1600 h, when the mean IOP was 16.5 mm Hg for travoprost-treated patients and 17.7 mm Hg for latanoprost-treated patients (p = 0.0025). When the treatment/IOP interval was >24 hours (n = 461), travoprost was superior to latanoprost, i.e. more patients using travoprost attained the predefined target IOP (78.5% vs 68.3%; p = 0.0344), and the mean IOP value was lower in the travoprost group (16.8 vs 17.8 mm Hg; p = 0.0016). After adjustments for confounding factors, similar results were obtained.

CONCLUSIONS

According to this observational survey, travoprost appears to reduce evening and mean diurnal IOP more effectively than latanoprost. Latanoprost IOP control appears to be more sensitive to time since the last dose.