Volume 19, Number 25Monday, June 24, 2019JUNE IS FIREWORKS EYE SAFETY & CATARACT AWARENESS MONTH In this issue: (click heading to view article)
Lipid-lowering Meds Associated with Lower Retinopathy Risk in DiabetesResearchers evaluated the impact of lipid-lowering medications on diabetic retinopathy and diabetic complications requiring intervention in the U.S. population, as part of a retrospective cohort analysis. They looked at administrative insurance claims drawn from the Truven MarketScan Commercial Claims and Encounters database. The population included beneficiaries with type 2 diabetes mellitus (T2DM).The main outcome measure was any sign of diabetic retinopathy, as measured by diagnosis codes for non-proliferative diabetic retinopathy, proliferative diabetic retinopathy, diabetic macular edema and procedure codes for retinopathy treatments (anti-VEGF injections, laser therapy and vitrectomy). Researchers analyzed a population of 269,782 individuals diagnosed with T2DM between 2008 and 2015. A total of 99,233 (37 percent) of people were undergoing treatment with lipid-lowering medications. Approximately 6 percent of individuals on lipid-lowering medications had a diagnosis code for NPDR, PDR or DME, or a procedural code for intravitreal injections, PPV or laser in their record following diagnosis with diabetes. This was in comparison with 6.5 percent of people who didn’t take lipid-lowering medications (p<0.01). Researchers found that, in adjusted time-to-event analyses, individuals who took lipid-lowering medications prior to diagnosis with T2DM were less likely to progress to any retinopathy diagnosis (HR 0.60, CI 0.55 to 0.65) and less likely to receive any treatment for retinopathy (HR 0.81, CI 0.78 to 0.84). These findings were significant at the aggregate level, as well as at the level of individual diagnosis (NPDR HR 0.63: CI, 0.57 to 0.69; PDR HR 0.45: CI, 0.37 to 0.54; and DME HR 0.39: CI, 0.33 to 0.45), and at the level of each treatment category (anti-VEGF injection HR 0.81: CI, 0.78 to 0.84; laser HR 0.62: CI, 0.47 to 0.81; and vitrectomy HR 0.71: CI, 0.59 to 0.85). Researchers found consistent evidence that individuals on lipid-lowering medications were less likely to develop NPDR, PDR or DME, and modest evidence that these individuals were less likely to receive intravitreal injections of anti-VEGF medication, laser treatments or vitrectomy. They wrote that the findings validated others found in studies that have used claims databases in East Asia in relatively homogeneous populations to estimate an association between statin use and retinopathy, and replicated them in a U.S. context in a large commercial claims database. SOURCE: Vail D, Callaway NF, Ludwig CA, et al. Lipid-lowering medications are associated with lower risk of retinopathy and ophthalmic interventions among U.S. patients with diabetes. Am J Ophthalmol 2019; Jun 10. [Epub ahead of print].
Schiotz Scleral IOP Readings Predict Goldmann Readings Better Than Rebound TonometryInvestigators studied the agreement between scleral intraocular pressure measurements using the Schiotz, Icare and Icare PRO tonometers vs. the Goldmann applanation tonometer in eyes with nonscarred corneas. This cross-sectional study included 83 eyes of 55 subjects. The order of IOP estimation was the corneal GAT, followed by ICare, ICare Pro and Schiotz on the corneal and temporal sclera.Investigators assessed agreement between the different tonometers and the 95% limits of agreement (LoA) using Bland-Altman plots. They calculated the repeated measures correlation coefficient between GAT IOP and scleral Schiotz IOP, and calculated confidence intervals by the bootstrap method. They used the linear mixed effects model (adjusted for both eyes of subjects) to generate an equation to predict GAT IOP from scleral Schiotz IOP. The prediction model was validated with new data from 60 eyes. Investigators performed statistical analyses using “R” software (version 3.3.2). Here were some of the findings: • For scleral IOP measurements, the mean IOP difference (LoA) was the lowest with Schiotz, underestimating by -1.21 mmHg (7.32, -9.74). • ICare and ICare Pro significantly overestimated GAT IOP: ICare, 24.6 mmHg (53.2, -3.97); and ICare Pro, 21.56 mmHg (52.9, -9.79). • The correlation coefficient between scleral Schiotz and GAT IOP was 0.92 (95% bootstrap CI: 0.89, 98). • The derived predictive equation was predicted GAT IOP=0.32 + (Schiotz IOP × 1.04). • The mean difference between the predicted GAT IOP and the actual GAT IOP was 0.96 mmHg with narrow LoA (+1.79, -3.71), validating the prediction model. Investigators concluded that, among the tonometers tested, the scleral IOP measurements with Schiotz had the best agreement with the GAT although limits of agreement were wide. They added that the predictive equation might have potential to predict GAT IOP from scleral IOP readings in eyes with scarred/prosthetic corneas. SOURCE: Senthil S, Chary RB, Ali MH, et al. Schiotz scleral intraocular pressure readings predict goldmann applanation readings better than rebound tonometry. Cornea 2019; June 13. [Epub ahead of print]. Using OCT to Characterize Clinical Diversity in Macular Corneal DystrophyScientists characterized the corneal deposits of macular corneal dystrophy with high-resolution optical coherence tomography. They evaluated 23 eyes of 15 individuals for clinical features on slit-lamp biomicroscopy, and performed high-resolution OCT to correlate the findings. They characterized the deposits based upon location and level in the corneal layers.The mean age was 31.5 (range: 20 to 67) years. Here were some of the findings: • Stromal deposits were restricted to central 8 mm in nine eyes; in the rest of the 14 eyes, the deposits were seen in both central and peripheral cornea. In one subject, no such distinction could be made due to the diffuse nature of the deposits throughout the cornea, with sparing of 1 to 2 mm of the cornea internal to the limbus. • Central deposits were in the anterior stromal layers, while peripheral deposits were in the deep stromal corneal layers and were non-contiguous with the anterior stromal deposits. • In one 67-year-old subject, peripheral deposits in the deep corneal layers were more prominent than the central anterior stromal deposits and were associated with a significant thickening of Descemet’s membrane. Scientists determined that MCD exhibited a clinically diverse presentation, as revealed on the clinical exam and OCT study. They added that immunophenotype and genotype-phenotype correlation might further help in understanding the various clinical presentations of MCD. SOURCE: Chaurasia S, Ramappa M, Mishra DK. Clinical diversity in macular corneal dystrophy: An optical coherence tomography study. Int Ophthalmol 2019; June 3. [Epub ahead of print]. Effects of Brimonidine & Timolol on Progression of VF Defects in OAGResearchers evaluated and compared the effects of 0.1% brimonidine and 0.5% timolol on progressing visual field defects in open-angle glaucoma. They evaluated one eye each of 68 glaucoma patients treated with at least one prostaglandin analog.Baseline mean deviation slopes were < -0.5 dB/y, based on at least five Humphrey field analyzer measurements within three years. Eligible eyes were randomly assigned to brimonidine or timolol treatment groups, and treatments were administered without a washout period. Clinical exams were performed every four months for two years. Researchers designated the mean deviation slope as the primary endpoint. A total of 56 eyes were included (mean age=65.2 y). It's unclear from the study's abstract the exact number in each group, but they were roughly equivalent. Here were some of the findings: • The dropout rate in the brimonidine group was 27.8 percent vs. 6.3 percent in the timolol group. • Researchers found no significant differences in baseline IOP: 12.7 mmHg for the brimonidine group, 12.9 mmHg for the timolol group (p=0.77) or mean deviation slopes between the brimonidine group (-1.22) and timolol group (-1.08 dB/y)(p=0.43). • IOP decreased significantly in the brimonidine group at four, eight, 12 and 16 months, and in the timolol group at four months, without significant differences between the drugs (p=0.20). • Mean deviation slopes significantly improved in both groups (brimonidine: -0.38 dB/y, p<0.001; timolol: -0.52 dB/y, p=0.04). • No significant difference between groups were found for the primary endpoint (p=0.59). Researchers reported that both brimonidine and timolol treatments improved mean deviation slopes in OAG. SOURCE: Yokoyama Y, Kawasaki R, Takahashi H, et al. Effects of brimonidine and timolol on the progression of visual field defects in open-angle glaucoma: A single-center randomized trial. J Glaucoma 2019; Jun 10. [Epub ahead of print]. BRIEFLY Glaukos Enters Agreement to Acquire DOSE Medical RIBOMIC Announces Topline Results from Phase I/IIA RBM-007 Trial Review of Ophthalmology® Online is published by the Review Group, a Division of Jobson Medical Information LLC (JMI), 11 Campus Boulevard, Newtown Square, PA 19073. |