Cost Evaluation of Early Vitrectomy versus Panretinal Photocoagulation and Intravitreal Ranibizumab for Proliferative Diabetic Retinopathy

Genipin ameliorates diabetic retinopathy via the HIF-1α and AGEs-RAGE pathways

BACKGROUND

Traditional Chinese medicine (TCM) is useful in disease treatment and prevention. Genipin is an active TCM compound used to treat diabetic retinopathy (DR). In this study, a network pharmacology (NP)-based approach was employed to investigate the therapeutic mechanisms underlying genipin administration in DR.

METHODS

The potential targets of DR were identified using the gene expression omnibus (GEO) database. TCM database screening and NP were used to predict the potential active targets and pathways of genipin in DR. Cell viability was tested in vitro to determine the effects of different doses of glucose and genipin on Human Retinal Microvascular Endothelial Cells (hRMECs). CCK-8, CCK-F, colony formation, CellTiter-Lum, Annexin V-FITC, wound healing, Transwell, tube-forming, reactive oxygen species (ROS), and other assay kits were used to detect the effects of genipin on hRMECs during high levels of glucose. In vivo, a streptozotocin (STZ)-mouse intraocular genipin injection (IOI.) model was used to explore the effects of genipin on diabetes-induced retinal dysfunction. Western blotting was performed to identify the cytokines involved in proliferation, apoptosis, angiogenesis, ROS, and inflammation. The protein expression of the AKT/ PI3K/ HIF-1α and AGEs/ RAGE pathways was also examined.

RESULTS

Approximately 14 types of TCM, and nearly 300 active ingredients, including genipin, were identified. The NP approach successfully identified the HIF-1α and AGEs-RAGE pathways, with the EGR1 and UCP2 genes, as key targets of genipin in DR. In the in vitro and in vivo models, we discovered that high glucose increased cell proliferation, apoptosis, angiogenesis, ROS, and inflammation. However, genipin application regulated cell proliferation and apoptosis, inhibited angiogenesis, and reduced ROS and inflammation in the HRMECs exposed to high glucose. Furthermore, the retinal thickness in the genipin-treated group was lower than that in the untreated group. AKT/ PI3K/ HIF-1α and AGEs/ RAGE signaling was increased by high glucose levels; however, genipin treatment decreased AKT/ PI3K and AGEs/ RAGE pathway expressions. Genipin also increased HIF-1α phosphorylation, oxidative phosphorylation of ATP synthesis, lipid peroxidation, and the upregulation of oxidoreductase. Genipin was found to protect HG-induced hRMECs and the retina of STZ-mice, based on; 1 the inhibition of UCP2 and Glut1 decreased intracellular glucose, and glycosylation; 2 the increased presence of HIF-1α, which increased oxidative phosphorylation and decreased substrate phosphorylation; 3 the increase in oxidative phosphorylation from ATP synthesis increased lipid peroxidation and oxidoreductase activity, and; 4 the parallel effect of phosphorylation and glycosylation on vascular endothelial growth factor (VEGF), MMP9, and Scg3.

CONCLUSION

Based on NP, we demonstrated the potential targets and pathways of genipin in the treatment of DR and confirmed its effective molecular mechanism in vitro and in vivo. Genipin protects cells and tissues from high glucose levels by regulating phosphorylation and glycosylation. The activation of the HIF-1α pathway can also be used to treat DR. Our study provides new insights into the key genes and pathways associated with the prognosis and pathogenesis of DR.

Counting the Cost of Cellular and/or Tissue Based Products in Diabetic Foot Ulcers: Is There a Justifiable Price Limit Per Square cm?

OBJECTIVE

To identify how cellular and/or tissue-based products (CTPs) relate to value in terms of cost per quality-adjusted life years in wound care with comparisons to treatments in other medical fields.

APPROACH

This is a cross-sectional study, cost-effectiveness analysis. Payment limits for each CTP were obtained via HCPCS Q codes and formulated as cost inputs into a cost-utility model published for treatment of Wagner 1 diabetic foot ulcers using dHACA versus standard of care. Additional changes to cap number of CTP applications and adjust for recent inflation were made. The literature was searched for other cost-utility models in other medical fields as comparisons.

RESULTS

When the payment limit was ≤$140 per square cm interventions were dominant (less costly, better outcomes) compared to standard of care. When the limit exceeded $430 per square cm the cost-effectiveness threshold of $100,000/QALY was exceeded. Newer Q codes are generally much more expensive and likely to not be cost-effective in comparison to the results for many other chronic diseases considered to be more serious than chronic wounds.

INNOVATION

This study presents decision-makers with tools by which they can determine as to whether a given CTP is likely to be cost-effective for patients.

CONCLUSION

Over a third of all CTPs will very likely result in non-cost-effective interventions. This number is likely to be higher when wounds are larger or used in other wound types where they are less efficacious. The recent trend in much higher costs for CTPs is worrisome.

Anti-Vascular Endothelial Growth Factor Drugs Compared With Panretinal Photocoagulation for the Treatment of Proliferative Diabetic Retinopathy: A Cost-Effectiveness Analysis

OBJECTIVES

This study aimed to evaluate the cost-effectiveness of anti-vascular endothelial growth factor drugs (anti-VEGFs) compared with panretinal photocoagulation (PRP) for treating proliferative diabetic retinopathy (PDR) in the United Kingdom.

METHODS

A discrete event simulation model was developed, informed by individual participant data meta-analysis. The model captures treatment effects on best corrected visual acuity in both eyes, and the occurrence of diabetic macular edema and vitreous hemorrhage. The model also estimates the value of undertaking further research to resolve decision uncertainty.

RESULTS

Anti-VEGFs are unlikely to generate clinically meaningful benefits over PRP. The model predicted anti-VEGFs be more costly and similarly effective as PRP, generating 0.029 fewer quality-adjusted life-years at an additional cost of £3688, with a net health benefit of -0.214 at a £20 000 willingness-to-pay threshold. Scenario analysis results suggest that only under very select conditions may anti-VEGFs offer potential for cost-effective treatment of PDR. The consequences of loss to follow-up were an important driver of model outcomes.

CONCLUSIONS

Anti-VEGFs are unlikely to be a cost-effective treatment for early PDR compared with PRP. Anti-VEGFs are generally associated with higher costs and similar health outcomes across various scenarios. Although anti-VEGFs were associated with lower diabetic macular edema rates, the number of cases avoided is insufficient to offset the additional treatment costs. Key uncertainties relate to the long-term comparative effectiveness of anti-VEGFs, particularly considering the real-world rates and consequences of treatment nonadherence. Further research on long-term visual acuity and rates of vision-threatening complications may be beneficial in resolving uncertainties.

Regression of Neovascularization after Panretinal Photocoagulation Combined with Anti-VEGF Injection for Proliferative Diabetic Retinopathy-A Review

Proliferative diabetic retinopathy (PDR) poses a significant therapeutic problem that often results in severe visual loss. Panretinal photocoagulation (PRP) has long been a mainstay treatment for this condition. Conversely, intravitreal anti-VEGF therapy has served as an alternative treatment for PDR. This review aimed to evaluate the effects of PRP combined with anti-VEGF therapy on the regression of neovascularization (NV), including functional outcomes and incidence of complications. The MEDLINE database was searched for articles evaluating regression of NV using a combination of the following terms: "proliferative diabetic retinopathy", "anti-VEGF", "panretinal photocoagulation", and "combined treatment". The search yielded a total of 22 articles. The analysis of their results indicated PRP combined with ant-VEGF therapy as superior over PRP alone in the management of PDR. Combination treatment yields better and faster regression of NV and a lower incidence of serious complications, such as vitreous hemorrhage and the need for pars plana vitrectomy. Nevertheless, complete regression of NV is not achieved in a significant proportion of patients. Further research is needed to establish the most effective schedule for intravitreal injections as an adjunct to PRP. The current literature shows that in some cases, cessation of anti-VEGF injection in combination treatment for PDR can lead to relapse of NV.

Cost-effectiveness of the anti-vascular endothelial growth factor intravitreal injection and panretinal photocoagulation for patients with proliferative diabetic retinopathy in South Korea

BACKGROUND

We determined the cost-effectiveness of the anti-vascular endothelial growth factor (VEGF) intravitreal injection versus panretinal photocoagulation (PRP) for patients with proliferative diabetic retinopathy (PDR) in South Korea.

METHODS

We simulated four treatment strategies using PRP and the anti-VEGF injection by constructing a Markov model for a hypothetical cohort of 50-year-old PDR patients: (1) PRP only; (2) anti-VEGF injection only; (3) PRP first; and (4) anti-VEGF injection first.

RESULTS

In this cost-effectiveness analysis, compared with only-PRP, the incremental cost-effectiveness ratio was $95,456 per quality-adjusted life-year (QALY) for PRP first, $34,375 per QALY for anti-VEGF injection first, and $33,405 per QALY for anti-VEGF injection only from a healthcare perspective. From the societal and payer perspective, strategy (2) was more cost-saving and effective than (1). In the probabilistic sensitivity analysis, only-PRP was cost-effective up to the willingness-to-pay (WTP) of about $42,000, while anti-VEGF injection only was cost-effective from a healthcare perspective. From the societal and payer perspectives, regardless of the value of WTP, anti-VEGF injection only was the most cost-effective strategy.

CONCLUSION

In our study, the anti-VEGF injection for PDR was cost-effective from the payer and societal perspectives.

Individual and Systems-Based Risk Factors for Diabetic Vitrectomy in an Urban Safety-Net Hospital

OBJECTIVE

To identify individual and systems-focused risk factors for pars plana vitrectomy among patients with proliferative diabetic retinopathy (PDR) in a diverse, urban, safety-net hospital setting.

DESIGN

Single-center, retrospective, observational, case-control study at Zuckerberg San Francisco General Hospital and Trauma Center between 2017 and 2022.

SUBJECTS

Two hundred twenty-two patients with PDR over a 5-year span (2017-2022), consisting of 111 cases who underwent vitrectomy for vision-threatening complications (tractional retinal detachment, nonclearing vitreous hemorrhage, and neovascular glaucoma) and 111 controls with PDR with no history of vitrectomy or vision-threatening complications. Controls were matched 1:1 through incidence density sampling.

METHODS

Medical records were reviewed from time of entry into hospital system to vitrectomy date (or date-matched clinic visit for controls). Individual-focused exposures included age, gender, ethnicity, language, homelessness, incarceration, smoking status, area deprivation index, insurance status, baseline retinopathy stage, baseline visual acuity, baseline hemoglobin A1c, panretinal photocoagulation status, and cumulative anti-VEGF treatments. System-focused exposures included external department involvement, referral route, time within hospital and ophthalmology systems, interval between screening and ophthalmology appointment, interval between conversion to proliferative disease and panretinal photocoagulation or first treatment, and loss-to-follow-up in intervals of active proliferative disease.

MAIN OUTCOME MEASURES

Odds ratios (ORs) for each exposure on vision-threatening diabetic complications requiring vitrectomy.

RESULTS

The absence of panretinal photocoagulation was the primary significant individual-focused risk factor for vitrectomy in the multivariable analysis (OR, 4.78; P = 0.011). Systems-focused risk factors included longer interval between PDR diagnosis and initial treatment (weeks; OR, 1.06; P = 0.024) and greater cumulative duration of loss-to-follow-up during intervals of active PDR (months; OR, 1.10; P = 0.002). Greater duration in the ophthalmology system was the primary systems-focused protective factor against vitrectomy (years; OR, 0.75; P = 0.035).

CONCLUSIONS

Largely modifiable variables modulate risk of complications requiring diabetic vitrectomy. Each additional month of loss-to-follow-up for patients with active proliferative disease increased odds of vitrectomy by 10%. Optimizing modifiable factors to promote earlier treatment and maintain critical follow-up in proliferative disease may reduce vision-threatening complications requiring vitrectomy in a safety-net hospital setting.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Anti-vascular endothelial growth factor for proliferative diabetic retinopathy

BACKGROUND

Proliferative diabetic retinopathy (PDR) is an advanced complication of diabetic retinopathy that can cause blindness. It consists of the presence of new vessels in the retina and vitreous haemorrhage. Although panretinal photocoagulation (PRP) is the treatment of choice for PDR, it has secondary effects that can affect vision. Anti-vascular endothelial growth factor (anti-VEGF), which produces an inhibition of vascular proliferation, could improve the vision of people with PDR.

OBJECTIVES

To assess the effectiveness and safety of anti-VEGFs for PDR and summarise any relevant economic evaluations of their use.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 6); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov, and the WHO ICTRP. We did not use any date or language restrictions. We last searched the electronic databases on 1 June 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing anti-VEGFs to another active treatment, sham treatment, or no treatment for people with PDR. We also included studies that assessed the combination of anti-VEGFs with other treatments. We excluded studies that used anti-VEGFs in people undergoing vitrectomy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, extracted data, and assessed the risk of bias (RoB) for all included trials. We calculated the risk ratio (RR) or the mean difference (MD), and 95% confidence intervals (CI). We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 15 new studies in this update, bringing the total to 23 RCTs with 1755 participants (2334 eyes). Forty-five per cent of participants were women and 55% were men, with a mean age of 56 years (range 48 to 77 years). The mean glycosylated haemoglobin (Hb1Ac) was 8.45% for the PRP group and 8.25% for people receiving anti-VEGFs alone or in combination. Twelve studies included people with PDR, and participants in 11 studies had high-risk PDR (HRPDR). Twelve studies were of bevacizumab, seven of ranibizumab, one of conbercept, two of pegaptanib, and one of aflibercept. The mean number of participants per RCT was 76 (ranging from 15 to 305). Most studies had an unclear or high RoB, mainly in the blinding of interventions and outcome assessors. A few studies had selective reporting and attrition bias. No study reported loss or gain of 3 or more lines of visual acuity (VA) at 12 months. Anti-VEGFs ± PRP probably increase VA compared with PRP alone (mean difference (MD) -0.08 logMAR, 95% CI -0.12 to -0.04; I2 = 28%; 10 RCTS, 1172 eyes; moderate-certainty evidence). Anti-VEGFs ± PRP may increase regression of new vessels (MD -4.14 mm2, 95% CI -6.84 to -1.43; I2 = 75%; 4 RCTS, 189 eyes; low-certainty evidence) and probably increase a complete regression of new vessels (RR 1.63, 95% CI 1.19 to 2.24; I2 = 46%; 5 RCTS, 405 eyes; moderate-certainty evidence). Anti-VEGFs ± PRP probably reduce vitreous haemorrhage (RR 0.72, 95% CI 0.57 to 0.90; I2 = 0%; 6 RCTS, 1008 eyes; moderate-certainty evidence). Anti-VEGFs ± PRP may reduce the need for vitrectomy compared with eyes that received PRP alone (RR 0.67, 95% CI 0.49 to 0.93; I2 = 43%; 8 RCTs, 1248 eyes; low-certainty evidence). Anti-VEGFs ± PRP may result in little to no difference in the quality of life compared with PRP alone (MD 0.62, 95% CI -3.99 to 5.23; I2 = 0%; 2 RCTs, 382 participants; low-certainty evidence). We do not know if anti-VEGFs ± PRP compared with PRP alone had an impact on adverse events (very low-certainty evidence). We did not find differences in visual acuity in subgroup analyses comparing the type of anti-VEGFs, the severity of the disease (PDR versus HRPDR), time to follow-up (< 12 months versus 12 or more months), and treatment with anti-VEGFs + PRP versus anti-VEGFs alone. The main reasons for downgrading the certainty of evidence included a high RoB, imprecision, and inconsistency of effect estimates.

AUTHORS' CONCLUSIONS

Anti-VEGFs ± PRP compared with PRP alone probably increase visual acuity, but the degree of improvement is not clinically meaningful. Regarding secondary outcomes, anti-VEGFs ± PRP produce a regression of new vessels, reduce vitreous haemorrhage, and may reduce the need for vitrectomy compared with eyes that received PRP alone. We do not know if anti-VEGFs ± PRP have an impact on the incidence of adverse events and they may have little or no effect on patients' quality of life. Carefully designed and conducted clinical trials are required, assessing the optimal schedule of anti-VEGFs alone compared with PRP, and with a longer follow-up.

Long-Term Outcomes of Same Patient Eyes Treated with Pars Plana Vitrectomy in One Eye and Conventional Treatment in the Other for Complications of Proliferative Diabetic Retinopathy

The purpose of this study was to evaluate the long-term, real-world outcomes of pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy. A retrospective review involving 64 patients with proliferative diabetic retinopathy that underwent PPV in their worse-seeing eye were followed for a minimum of 8 years. The fellow eye underwent conventional treatment. Patients were divided into two groups by age: patients younger than 50 years of age and patients older than 50. In the younger than 50 group, 89% of vitrectomized eyes had improved visual acuity (VA) while 3.6% had decreased VA. A total of 14% of vitrectomized eyes required additional laser and 11% required reoperations. In the conventional treatment eyes, 25% had improved VA while 68% had decreased VA (p < 0.05). A total of 72% required additional laser and 60% required PPV. In the older than 50 group, 86% of vitrectomized eyes had VA improvement and 3% had decreased VA. A total of 8% required laser and 8% required reoperations. In the conventional treatment eyes, 30% improved VA and 48% had decreased VA (p < 0.05). Additional procedures required included laser in 70% and PPV in 17%. In both age groups, eyes that underwent PPV had better final visual outcomes than eyes that received conventional treatment for PDR.

A Cost Effectiveness Analysis of Intravitreal Aflibercept for the Prevention of Progressive Diabetic Retinopathy

PURPOSE

To calculate costs required to prevent center-involved diabetic macular edema (CI-DME) or proliferative diabetic retinopathy (PDR), and to improve the diabetic retinopathy severity score (DRSS) with intravitreal anti-VEGF injections as reported for aflibercept in two randomized control trials.

DESIGN

Cost-effectiveness analysis modeling based on published data SUBJECTS: None METHODS: Results from PANORAMA and the Diabetic Retinopathy Clinical Research Network (DRCR.net) Protocol W were analyzed. Parameters collected included DRSS score, risk reduction of PDR, risk reduction of CI-DME, and number of treatments required. Costs were modeled based on 2020 Medicare reimbursement data practice settings of hospital-based facility and non-facility.

MAIN OUTCOME MEASURE

Cost to prevent case of PDR and CI-DME, and to improve DRSS stage RESULTS: Over 2 years in Protocol W, the cost required to prevent 1 case of PDR was $83,000 ($72,400) in the facility (non-facility) setting; in PANORAMA, the corresponding 2 year costs were $89,400 ($75,000) for the 2Q16 arm, and $91,200 ($89,900) for the 2Q8PRN arm. To prevent 1 case of CI-DME with vision loss in Protocol W, the cost was $154,000 ($133,000). For all CI-DME, with and without vision loss; in PANORAMA, the costs to prevent a case were $70,900 ($59,500) for the 2Q16 arm, and $90,000 ($88,800) for the 2Q8PRN arm. In Protocol W, the overall accumulated total for cost /DRSS unit change at the 2 year point for facility (non-facility) setting was $2700 ($2400)/DRSS. In the first year alone, it was $2100 ($1800)/DRSS and in the second year alone, $6100 ($5300)/DRSS.

CONCLUSION

There is a considerable cost associated with the prevention of PDR and CI-DME with intravitreal aflibercept injections. A price per unit of change in diabetic retinopathy severity score is a new parameter which might serve as a benchmark in future utility analyses that could be used to bring perspective to cost-utility considerations.

Intravitreal anti-vascular endothelial growth factors, panretinal photocoagulation and combined treatment for proliferative diabetic retinopathy: a systematic review and network meta-analysis

PURPOSE

To conduct a systematic review with network meta-analysis (NMA) of randomized clinical trials (RCTs) comparing panretinal photocoagulation (PRP) versus anti-vascular endothelial growth factor (VEGF) treatment alone or in combination with PRP, for proliferative diabetic retinopathy (PDR).

METHODS

PubMed, Medline and Embase databases were searched for RCTs comparing PRP versus intravitreal anti-VEGF therapy and/or combined PRP and intravitreal anti-VEGF for PDR. The primary outcome measures were the mean best corrected visual acuity (BCVA) change and the regression of neovascularization. Mean change of central macular thickness (CMT), the subgroup analyses of patients without diabetic macular oedema (DME) and the rate of vitreous haemorrhage and vitrectomy were secondary outcomes. Frequentist NMAs were performed.

RESULTS

Twelve RCTs were included. For the 12-month mean BCVA change, NMA showed a better visual outcome in both the anti-VEGF group and combined group compared to PRP [anti-VEGF vs PRP, mean difference (MD) = 3.42; standard error (SE) = 1.5; combined vs PRP, MD = 3.92; SE = 1.65], with no difference between combined group and anti-VEGF (MD = -0.50; SE = 1.87). No difference in neovascularization regression was found between PRP and anti-VEGF alone or in combination with PRP, but there was significant inconsistency (p = 0.016). Subgroup analyses in patients without DME yielded no difference for the 12-month visual outcome between the three interventions, but with significant inconsistency (p = 0.005).

CONCLUSION

This NMA showed limited evidence of comparable efficacy in terms of neovascularization regression between PRP and anti-VEGF therapy alone or in combination with PRP, but better visual outcomes were associated with anti-VEGF use. Intravitreal anti-VEGF therapy could be a valid therapeutic option in association with PRP.

The Use of Decision Analytic Modeling in the Evaluation of Surgical Innovations: A Scoping Review

OBJECTIVES

The main objective of this review was to map how decision analytic models are used in surgical innovation (in which research phase, with what aim) and to understand how challenges related to the assessment of surgical interventions are incorporated.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library for studies published in 2018. We included original articles using a decision analytic model to compare surgical strategies. We included modeling studies of surgical innovations. General, innovation, and modeling characteristics were extracted, as were outcomes, recommendations, and handling of challenges related to the assessment of surgical interventions (learning curve, incremental innovation, dynamic pricing, quality variation, organizational impact).

RESULTS

We included 46 studies. The number of studies increased with each research phase, from 4% (n = 2) in the preclinical phase to 40% (n = 20) in phase 3 studies. Eighty-one studies were excluded because they investigated established surgical procedures, indicating that modeling is predominantly applied after the innovation process. Regardless of the research stage, the aim to determine cost-effectiveness was most frequently identified (n = 40, 87%), whereas exploratory aims (eg, exploring when a strategy becomes cost-effective) were less common (n = 9, 20%). Most challenges related to the assessment of surgical interventions were rarely incorporated in models (eg, learning curve [n = 1, 2%], organizational impact [n = 2, 4%], and incremental innovation [n = 1, 2%]), except for dynamic pricing (n = 10, 22%) and quality variation (n = 6, 13%).

CONCLUSIONS

In surgical innovation, modeling is predominantly used in later research stages to assess cost-effectiveness. The exploratory use of modeling seems still largely overlooked in surgery; therefore, the opportunity to inform research and development may not be optimally used.

Early pars plana vitrectomy for proliferative diabetic retinopathy: update and review of current literature

PURPOSE OF REVIEW

Diabetic retinopathy (DR) is one of the leading causes of preventable vision loss in the world and its prevalence continues to increase worldwide. One of the ultimate and visually impairing complications of DR is proliferative diabetic retinopathy (PDR) and subsequent tractional retinal detachment. Treatment modalities, surgical techniques, and a better understanding of the pathophysiology of DR and PDR continue to change the way we approach the disease. The goal of this review is to provide an update on recent treatment modalities and outcomes of proliferative diabetic retinopathy and its complications including tractional retinal detachment.

RECENT FINDINGS

Panretinal photocoagulation (PRP), anti-vascular endothelial growth factor (anti-VEGF), and pars plana vitrectomy are the mainstay of PDR treatment. However, PRP and anti-VEGF are associated with significant treatment burden and multiple subsequent treatments. Early vitrectomy is associated with vision preservation, less treatment burden, and less subsequent treatments than therapy with PRP and anti-VEGF.

SUMMARY

Concerning costs, high rates of noncompliance in the diabetic population and significant rates of subsequent treatments with initial PRP and anti-VEGF, early vitrectomy for diabetic retinopathy in patients at risk of PDR is a cost-effective long-term stabilizing treatment for diabetics with advanced disease.

Aqueous humor monocyte chemoattractant protein-1 predicted long-term visual outcome of proliferative diabetic retinopathy undergone intravitreal injection of bevacizumab and vitrectomy

PURPOSE

We aim to investigate the risk factors associated with the prognosis of proliferative diabetic retinopathy (PDR) after a sequential treatment of intravitreal injection of bevacizumab (IVB) and pars plana vitrectomy (PPV).

METHODS

In this cohort study, 63 eyes from 55 patients (21 females) diagnosed with PDR, who needed PPV for non-clearing vitreous hemorrhage or fibrovascular membrane proliferation were enrolled. All the eyes underwent IVB followed by PPV. Anterior chamber tap was performed at the beginning of both procedures to evaluate the concentration of vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-8, and monocyte chemoattractant protein (MCP)-1.

RESULTS

Forty-seven patients (54 eyes) were followed over six months, averaging 12±5 (6-19) months. The concentration of VEGF significantly decreased after IVB (P<0.001), while other cytokines did not change significantly. The aqueous humor level of IL-8 after IVB (R = 0.378, P = 0.033), MCP-1 before (R = 0.368, P = 0.021) and after (R = 0.368, P = 0.038) IVB, and combined phacoemulsification (R = 0.293, P = 0.032) was correlated with the logMAR visual acuity at the last follow-up. Multivariate analysis showed that MCP-1 was the predictor for a worse visual outcome (B = 0.108, 95% CI 0.013-0.202; P = 0.027).

CONCLUSIONS

MCP-1 was a predictor for the unfavorable visual outcome of PDR after IVB pretreatment and PPV.

Effectiveness and Safety of Coadministration of Intravitreal Dexamethasone Implant and Silicone Oil Endotamponade for Proliferative Diabetic Retinopathy with Tractional Diabetic Macular Edema

Purpose: To investigate the efficacy and safety of coadministered intravitreal dexamethasone (IVD) implant and silicone oil endotamponade during pars plana vitrectomy (PPV) for the treatment of proliferative diabetic retinopathy (PDR) with tractional diabetic macular edema (DME). Methods: In this prospective, controlled, and randomized clinical study, the eyes with PDR and vitreomacular traction syndrome that underwent PPV with silicone oil endotamponade were divided into 2 groups. Group 1 was defined as the control group, and no other procedures were performed. IVD was implanted to the eyes in Group 2. In both groups, panretinal photocoagulation was completed to the missed areas during PPV. All cases followed for 6 months, postoperatively. Retinal findings were followed with optical coherence tomography and fluorescein fundus angiography. Results: A total of 52 eyes of 52 patients were included in the study. Twenty-six eyes of 23 patients were included in both groups. The improvement in best corrected visual acuity was statistically significantly higher in Group 2 (P > 0.05). In the postoperative period, the DME development rate and intravitreal ranibizumab (IVR) injection requirement were significantly higher in Group 1 (P > 0.05). There was no statistically significant difference in the proliferative vitroretinopathy development rate between the groups (P < 0.05). Conclusion: Coadministration of IVD implant and silicone oil endotamponade to the eyes with PDR during vitrectomy seems to be safe and effective application and may decrease the rate of DME and the requirement of IVR injection.

Cost-Utility of Anti-Vascular Endothelial Growth Factor Treatment for Macular Edema Secondary to Central Retinal Vein Occlusion

PURPOSE

To evaluate the cost-utility of treatment for macular edema in central retinal vein occlusion (CRVO) using intravitreal injections of the anti-vascular endothelial growth factor (VEGF) agents bevacizumab, ranibizumab, and aflibercept.

DESIGN

Decision analysis model of cost-utility.

PARTICIPANTS

Data from study participants in the Lucentis, Eylea, Avastin in Vein Occlusion (LEAVO) study.

METHODS

A decision analysis of a disease simulation model was used to calculate comparative cost-utility of intravitreal bevacizumab (IVB), intravitreal ranibizumab (IVR), and intravitreal aflibercept (IVA) for the treatment of macular edema associated with CRVO based on data from the LEAVO study. Center for Medicare and Medicaid Services data were used to calculate associated modeled costs in a hospital- or facility-based and nonfacility setting from a third-party payer perspective, and societal costs also were calculated. Cost utility was calculated based on the preserved visual utility during the 2 years of the study and also by estimating utility for the expected lifetime.

MAIN OUTCOME MEASURES

Cost of treatment, cost per quality-adjusted life-year (QALY), and incremental cost-effectiveness ratio (ICER).

RESULTS

From the third-party payer perspective, the estimated lifetime costs per QALY in the facility and nonfacility settings were $39 325 and $17 944, respectively, for IVB; $114 095 and $92 653, respectively, for IVR; and $78 935 and $63 270, respectively, for IVA. From the societal perspective, the estimated lifetime costs per QALY in the facility setting were $52 754 for IVB, $128 242 for IVR, and $86 262 for IVA. The ICER of IVA compared with that of IVB was $153 633/QALY from the third-party facility setting and $152 992/QALY from the societal perspective. The use of IVB compared with IVR and IVA compared with IVR were cost-saving interventions (ICER, <0) regardless of the perspective or setting.

CONCLUSIONS

In the treatment of macular edema in CRVO, IVB yields the best cost utility among the 3 anti-VEGF agents modeled. Intravitreal aflibercept maintains acceptable lifetime cost per QALY while having a favorable cost utility compared with IVR.

Anti-Vascular Endothelial Growth Factor Therapy as an Alternative or Adjunct to Pan-Retinal Photocoagulation in Treating Proliferative Diabetic Retinopathy: Meta-Analysis of Randomized Trials

Aim

To compare anti-vascular growth factor (anti-VEGF) pharmacotherapy with pan-retinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR).

Method

PubMed, Embase, Medline, the ClinicalTrials.gov and the Cochrane Central Register of Controlled Trials were reviewed systemically. Randomized controlled trials (RCT) on anti-VEGF therapy versus PRP or anti-VEGF agent combined with PRP versus PRP for PDR are eligible to be included. Outcome measures were regression and recurrence of neovascularization, change in best corrected vision acuity, development of vitreous hemorrhage, and need for vitrectomy. A meta-analysis was conducted using RevMan (Cochrane Collaboration, Oxford, United Kingdom).

Results

Twelve RCTs with a total of 1026 eyes were identified. The meta-analysis results showed that regression of neovascularization did not vary significantly among different treatment regimens (P=0.06), whereas the recurrence of new vessels was significantly lower in PRP monotherapy (P < 0.00001). The best corrected visual acuity was significantly improved with anti-VEGF monotherapy or in the combined group than in the PRP groups (P < 0.00001, P=0.04, respectively). Odds ratio for post-treatment vitreous hemorrhage and vitrectomy rate between anti-VEGF therapy and PRP were 0.65 (95% confidence interval, 0.45–0.95; P = 0.03), and 0.24 (95% confidence interval, 0.12–0.48; P < 0.0001).

Conclusion

Our meta-analysis indicates that anti-VEGF pharmacotherapy is associated with superior visual acuity outcomes and less PDR-related complications. However, there is insufficient evidence to suggest anti-VEGF therapy as an alternative to PRP.

Intravitreal bevacizumab improves the clearance of vitreous haemorrhage and visual outcomes in patients with proliferative diabetic retinopathy

Objective

To evaluate the occurrence of vitreous haemorrhage (VH) secondary to proliferative diabetic retinopathy (PDR) and the efficacy of intravitreal bevacizumab (IVB) for VH in 5-year real-life data.

Methods and analysis

850 adult patients with type 1 (T1D) or type 2 diabetes (T2D) with PDR were screened for VH. The effect of IVB was evaluated by the clearage of VH and the change in best corrected visual acuity (BCVA). The rates of VHs, reinjections, macular oedema, complications, additional treatments and outcomes of spontaneous resorption, panretinal photocoagulation or pars plana vitrectomy (PPV) for VH were also investigated.

Results

VH occurred in 16% of patients with T1D and 9% of patients with T2D with PDR. 336 VHs in 140 eyes of 103 patients were documented. VH was cleared in 92% of cases in less than 3 months by the initial IVB. IVB was superior to other treatment methods in shortening the time for clearance of VH (Kaplan-Meier, p<0.0001). The average rate of IVB reinjections was 1.7±1.1 and the reinjection interval was 7.2±3.9 weeks. BCVA increased 0.73±0.04 logarithm of the minimum angle of resolution units after IVB (generalised estimating equations, p=0.0004). In 5 years, the patients had 2.2±2.7 recurrence of VHs. A simultaneous 72% decrease in the rate of PPVs was documented (p<0.0001).

Conclusion

VH occurs mostly in patients with T1D. The therapeutic effect of IVB for VH was significant and led to improved clearance of VH and visual outcome. Moreover, IVB prevented persistent and recurrent VHs and decreased the need for costly PPV.

Cost Effectiveness of Treatments for Diabetic Retinopathy: A Systematic Literature Review

BACKGROUND

Diabetic retinopathy (DR) affects approximately one-third of people diagnosed with diabetes, can be sight-threatening, and generates significant human and economic burden. Over the last 2 decades, newer therapies have emerged, offering significant clinical benefits, however at a cost. Given the scarcity of available budgets, the cost effectiveness of these newer treatments is of vital importance to policy makers.

METHODS

A systematic review was conducted in the PubMed, EMBASE, Cochrane, HEED and CRD databases to find and evaluate economic evaluations assessing the cost effectiveness of alterative DR treatments. Studies were assessed for their eligibility, findings and quality, and are presented in this systematic review.

RESULTS

Of the 5254 studies retrieved from the literature search, 17 were included in this review. For patients with proliferative DR, when early pars plana vitrectomy was compared with pan-retinal laser photocoagulation, similar cost per quality-adjusted life-year (QALY) was observed between the two. Treatment with either intravitreal ranibizumab (IVR) or intravitreal bevacizumab (IVB) falls within acceptable cost-effectiveness thresholds in the diabetic macular oedema (DMO) population; however, in the non-DMO population, the marginal benefit of IVR or IVB in relation to the marginal cost relative to laser does not justify their use. Among the anti-vascular endothelial growth factor (VEGF) therapies, IVB appears more attractive from an economic point of view due to its lower cost. For patients with DMO, studies indicate that a combination therapy of IVR or IVB with laser and, to a lesser degree, as monotherapy, are cost effective relative to laser monotherapy; IVR plus laser is cost effective relative to laser plus triamcinolone; and laser combined with triamcinolone injections is reportedly more cost effective over IVR for pseudophakic eyes only. Moreover, fluocinolone implants appear cost effective compared with sham implants, or when treating refractory DMO. IVR administered either pro re nata (PRN) or as 'treat and extend' dominated intravitreal aflibercept (IVA) in a few studies. On the other hand, IVR monotherapy or with laser (as well as IVA) does not compare favourably relative to IVB monotherapy or with laser.

CONCLUSIONS

Interpretation of cost-effectiveness data should be treated with caution in this case; details of the therapeutic regimen, such as dosage and frequency, and clinical efficacy of the treatments should be considered in relation to policy-making decisions. Given the scarcity of resources, the ever-increasing significance of health technology assessment, and the substantial differences in the methodologies of the studies presented in this review, there is a pressing need for more advanced and standardised approaches to assessing the effectiveness and cost effectiveness of the emerging anti-VEGF pharmacotherapies for the treatment of DMO.

Vitrectomy for macular edema due to retinal vein occlusion

Purpose: To determine the long-term outcomes of vitrectomy for the macular edema associated with a retinal vein occlusion (RVO).

Methods: This was a retrospective, consecutive, interventional case series. The intraoperative procedures included internal limiting membrane peeling, arteriovenous sheathotomy, radial optic neurotomy, and intravitreal triamcinolone acetonide injection at the end of the surgery. The main outcome was the best-corrected visual acuity (BCVA).

Results: Eight hundred and fifty-four eyes of 854 patients were studied. The eyes consisted of 602 with branch RVO (BRVO), 74 with hemi-central RVO (hemi-CRVO), 87 with nonischemic central retinal vein occlusion (CRVO), and 91 with ischemic CRVO. The mean follow-up period was 68.6 months with a range of 12 to 262 months. The mean BCVA was significantly improved at the final visit (P<0.0001 to 0.0016). The final BCVA improved in 74.4% of the BRVO eyes, in 58.1% of the hemi-CRVO eyes, in 57.4% of the nonischemic CRVO eyes, and in 51.6% of the ischemic CRVO eyes. Multiple regression analysis showed there was no significant relationship between the intraoperative combined procedures and the final BCVA.

Conclusions: The results indicate that the type of RVO is significantly associated with the final BCVA, and vitrectomy is a treatment option to improve and maintain BCVA for a long term.

Cost Analysis of Pneumatic Retinopexy versus Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment

PURPOSE

To perform a cost-utility analysis and comparison between pneumatic retinopexy (PR) and pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD) repair.

DESIGN

A cost-utility analysis using decision analysis.

PARTICIPANTS

There were no participants.

METHODS

A decision analysis model was constructed based on results from the Pneumatic Retinopexy versus Vitrectomy for the Management of Primary Rhegmatogenous Retinal Detachment Outcomes Randomized Trial to calculate the costs, lifetime usefulness, and lifetime cost per quality-adjusted life year (QALY) for the treatment of RRD with PR or PPV. Data from the Centers for Medicare and Medicaid Services were used to calculate the associated adjusted costs in facility and nonfacility practice settings.

MAIN OUTCOME MEASURES

Cost of intervention, utility gain over natural history, QALY gained, and cost per QALY.

RESULTS

The total imputed costs (all in 2019 United States dollars) for primary repair of RRD in facility and nonfacility settings were $4451 and $2456, respectively, in the PR group and $7108 and $4514, respectively, in the PPV group. The estimated lifetime QALYs gained were 5.9 and 5.4 in the PR and PPV groups, respectively. The cost per QALY for facility and nonfacility settings was $751 and $414, respectively, in the PR group and $1312 and $833, respectively, in the PPV group.

CONCLUSIONS

Cost-utility analysis of both PR and PPV demonstrated excellent results for both methods for RRD repair, with the metrics for PR somewhat more favorable independent of the practice settings (facility or nonfacility based).

Long-term outcomes of intravitreous bevacizumab or tissue plasminogen activator or vitrectomy for macular edema due to branch retinal vein occlusion

Purpose

The purpose of this study was to determine the long-term outcomes of intravitreal bevacizumab (IVB) or intravitreal tissue plasminogen activator (tPA) or vitrectomy for macular edema associated with a branch retinal vein occlusion (BRVO).

Methods

This was a retrospective, interventional case series. Forty-one patients received a single 1.25 mg of IVB injection and followed by pro re nata protocol, 71 patients received a single intravitreal tPA, and 116 patients underwent phacovitrectomy with intraocular lens implantation.

Results

The baseline characteristics and follow-up periods were not significantly different among the three groups. The mean follow-up period was 55.5 months with a range of 12-160 months. Sixteen patients (39.0%) in the IVB group, 24 patients (33.8%) in the tPA group, and two patients (1.7%) in the vitrectomy group underwent additional surgeries during the follow-up period. The best-corrected visual acuity (BCVA) significantly improved in all groups at 1 year after the initial treatment (all, P<0.0001) and at the final visit (all, P<0.0001). The differences in the BCVA between the three groups were not significant at all times after the initial treatment.

Conclusion

The three groups led to similar long-term good visual outcomes. However, additional surgeries were performed in more than 30% of patients in the IVB and tPA groups.

Decision Making in Proliferative Diabetic Retinopathy Treatment

Purpose of Review

The goal of this paper is to provide a comprehensive review of the recent advances in the management options for proliferative diabetic retinopathy.

Recent Findings

For many years cases of proliferative diabetic retinopathy (PDR) have been managed by pan retinal photocoagulation (PRP). The advent of anti-vascular endothelial growth factor (anti-VEGF) agents has changed the future of PDR management and has provided an alternative to PRP.

Summary

Management of PDR requires the identification of high risk characteristics for PDR and the decision regarding the most appropriate treatment modality. The risk to benefit ratio for each treatment modality must be considered in determining the appropriate choice between surgical intervention (PRP) versus medical intervention with anti-VEGF.