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To identify optical coherence tomography (OCT) biomarkers, including thin and thick double-layer sign (DLS) for the progression from intermediate AMD (iAMD) to exudative macular neovascularization (MNV) over 24 months.Retrospective cohort study.Setting: Retina consultants of Texas.458 eyes of 458 subjects with iAMD in at least 1 eye with 24 months of follow-up data.The following biomarkers were assessed at baseline: high central drusen volume (≥0.03 mmDuring follow-up, 18.1% (83 of 458) of eyes with iAMD progressed to exudative MNV. Thick DLS, IHRF, and fellow eye exudative MNV were found to be independent predictors for the development of exudative MNV within 2 years. The baseline frequencies, odds ratios, 95% confidence intervals, and P values for these biomarkers were as follows: thick DLS (9.6%, 4.339, 2.178-8.644; P.001), IHRF (36.0%, 2.340, 1.396-3.922; P = 0.001), and fellow eye exudative MNV (35.8%, 1.694, 1.012-2.837; P = .045).Thick DLS, IHRF, and fellow eye exudative MNV were associated with an increased risk of progression from iAMD to exudative MNV. These biomarkers, which are readily identified by the review of OCT volume scans, may aid in risk prognostication for patients and for identifying patients for early intervention trials.

Retinal nonperfusion (RNP) is an important biomarker for diabetic retinopathy (DR). Data suggest that consistent anti-VEGF pharmacotherapy can slow RNP development. The RECOVERY trial evaluated the impact of aflibercept (Eylea, Regeneron) on RNP among eyes with proliferative DR (PDR).Prospective, randomized clinical trial with treatment crossover in the second year.Eyes with PDR and RNP.At baseline, the subjects were randomized 1:1 to monthly (arm 1) or quarterly (arm 2) intravitreal 2 mg aflibercept. At the beginning of year 2, the treatment arms were crossed over so that the monthly-dosed subjects subsequently received quarterly dosing and the quarterly-dosed subjects subsequently received monthly dosing.Change in total RNP area (mmAmong all subjects, from baseline to year 2, the mean RNP increased from 235 mmThrough year 2 of the RECOVERY trial, both treatment arms experienced significant increases in RNP. Despite the expansion of the RNP area in nearly all subjects, 82% of subjects demonstrated an improvement in DRSS levels from baseline, with no subjects experiencing worsening in DRSS scores.

To assess outcomes among eyes undergoing surgery for recurrent rhegmatogenous retinal detachment (RRD) and investigate variables that correlate with visual and anatomic outcomes.Retrospective, consecutive case series.Eyes in which initial RRD repair failed that underwent ≥2 surgeries for RRD repair between January 1, 2016, and December 31, 2020.A retrospective analysis of eyes that underwent ≥2 RRD repairs. Eyes with etiologies of retinal detachment other than RRD, previous vitreoretinal surgery, and proliferative diabetic retinopathy were excluded. One-way analysis of variance with Tukey honestly significant difference testing and multivariate regression analyses were used to assess statistical significance.Anatomic success rate and habitual best recorded visual acuity (VA) at postoperative time intervals and at final follow-up.The single-operation success rate (SOSR) among eyes that underwent primary RRD repair over a 5-year period was 92.4% (2021 of 2187 eyes). The remaining 166 eyes (164 patients) in which primary RRD repair failed were included in this study. Although the anatomic success rates after the second and third RRD repairs were lower than the SOSR (71.7% and 68.1%, respectively), the final anatomic success rates did not significantly differ between eyes that underwent ≥2 RRD repairs (range, 90.6%-100%) (P0.05), and final anatomic success was achieved in 95.8% of the eyes. The average VA at both postoperative time intervals and final follow-up decreased with an increased total number of RRD repairs. Eyes that received silicone oil endotamponade during the second RRD repair were 20.3% (P = 0.03) and 38.4% (P = 0.04) less likely to require a third RRD repair compared with eyes that received octafluoropropane and sulfur hexafluoride gases, respectively. Eyes that developed a third RRD due to proliferative vitreoretinopathy (PVR) (n = 43) were 110% more likely to require a fourth RRD repair than eyes that developed a third RRD due to a new tear or failure to reattach (n = 4) (P = 0.04).In this series, the rates of anatomic success appeared consistent after each surgery when multiple reoperations were required for RRD. The VA decreased with an increased total number of RRD repairs, and the endotamponade choice might have affected the risk of additional reoperations. Proliferative vitreoretinopathy was a significant prognostic factor for RRD recurrence.

Purpose: The efficacy and safety of scleral buckling (SB) versus combination SB and pars plana vitrectomy (SB + PPV) for rhegmatogenous retinal detachment (RRD) repair remains unclear. Methods: A systematic review and meta-analysis was conducted to identify comparative studies published from Jan 2000–Jun 2021 that reported on the efficacy and/or safety following SB and SB + PPV for RRD repair. Final best-corrected visual acuity (BCVA) represented the primary endpoint, while reattachment rates and ocular adverse events were secondary endpoints. A random-effects meta-analysis was performed, and 95% confidence intervals were calculated. Results: Across 18 studies, 3912 SB and 3300 SB + PPV eyes were included. Final BCVA was nonsignificantly different between SB and SB + PPV (20/38 vs. 20/66 Snellen; WMD = −0.11 LogMAR; 95% CI: [–0.29, 0.07]; p = 0.23). Primary reattachment rate was similar between procedures (p = 0.74); however, SB alone achieved a significantly higher final reattachment rate (97.40% vs. 93.86%; RR = 1.03; 95% CI: [1.00, 1.06]; p = 0.04). Compared to SB + PPV, SB alone had a significantly lower risk of postoperative macular edema (RR = 0.69; 95% CI: [0.47, 1.00]; p = 0.05) and cataract formation (RR = 0.34; 95% CI: [0.12, 0.96]; p = 0.04). The incidence of macular hole, epiretinal membrane, residual subretinal fluid, proliferative vitreoretinopathy, elevated intraocular pressure, and extraocular muscle dysfunction were similar between SB and SB + PPV. Conclusions: There was no significant difference in final BCVA between SB + PPV and SB alone in RRD. SB alone offers a slightly higher final reattachment rate along with a reduced risk of macular edema and cataract. Primary reattachment rate and the incidence of other complications were similar between the two procedures.

To assess the efficacy of a treat-and-extend strategy with intravitreal ranibizumab for radiation-related macular edema. Forty eyes with radiation-induced macular edema and decreased visual acuity were enrolled in the phase IIb, prospective clinical trial and randomized into 3 cohorts: (A) monthly ranibizumab, (B) monthly ranibizumab with targeted retinal photocoagulation (TRP), or (C) as-needed ranibizumab and TRP. In year 2, all subjects entered a treat-and-extend protocol for ranibizumab. The primary outcome measure was mean change in early treatment diabetic retinopathy study (ETDRS) best-corrected visual acuity (BCVA) from baseline. Through year 1, the mean change in ETDRS BCVA was significantly different between the three cohorts (p

BackgroundThis study investigates the association of intraocular cytokine expression and ultrawide-field fluorescein angiography (UWFA) quantitative imaging biomarkers and their association with angiographical feature response after antivascular endothelial growth factor (VEGF) therapy in diabetic macular oedema (DME).MethodsThe IMAGINE DME study is a post hoc imaging biomarker and intraocular cytokine assessment from the DAVE study, a prospective DME clinical trial that included aqueous humour sampling and UWFA imaging. Fifty-four cytokines associated with inflammation and angiogenesis were evaluated through multiplex arrays. UWFA parameters were assessed using an automated feature analysis platform to determine ischaemic and leakage indices and microaneurysm (MA) count. Eyes were classified into UWFA responder or non-responder groups based on longitudinal quantitative UWFA parameter improvement. Cytokine expression was correlated with UWFA metrics and evaluated in the context of therapeutic response.ResultsTwenty-one eyes were included with a mean age of 55±10 years. Increased panretinal leakage index correlated with VEGF (r=0.70, p=0.0005), angiopoietin-like 4 (r=0.77, p=4.6E-5) and interleukin (IL)-6 (r=0.64, p=0.002). Panretinal ischaemic index was associated with tissue inhibitor of metalloproteinases 1 (TIMP-1, r=0.49, p=0.03) and peripheral ischaemia correlated with VEGF (r=0.45, p=0.05). MA count correlated with increased monocyte chemotactic protein-4 (MCP-4, r=0.60, p=0.004) and platelet and endothelial cell adhesion molecule 1 (PECAM-1, r=0.58, p=0.005). Longitudinal MA reduction was associated with decreased baseline VEGF and urokinase receptor (uPAR) (pConclusionsBaseline and longitudinal quantitative UWFA imaging parameters correlated with multiple aqueous humour cytokine concentrations, including VEGF and IL-6. Further research is needed to assess the possible implications of using these findings for evaluating treatment response.

To assess the safety and efficacy of as-needed (PRN) intravitreal aflibercept injections (IAI) in managing diabetic retinopathy (DR) guided by the real-time DR severity scale (DRSS) level or panretinal leakage index (PLI) assessment among eyes without diabetic macular edema (DME).Prospective, randomized phase 2 trial (PRIME).A total of 40 eyes with nonproliferative (NPDR) or proliferative DR (PDR) received monthly IAIs until a DRSS improvement of ≥2 steps was achieved and eyes were randomized (1:1) to DRSS-guided or PLI-guided management strategies graded by a central reading center. Main outcome measurements included safety and changes in DRSS and PLI.Through week 52, 95% of eyes achieved a DRSS improvement of ≥2 steps. Following DRSS improvement, 97% of eyes required at least 1 PRN IAI. In eyes requiring PRN IAI and completing week 52, 100% and 59% experienced DRSS worsening (P = .01) in the DRSS- and PLI-guided arms, respectively. Through week 52, mean PLI decreased 18.2% (P = .49) and 54.6% (P.0001), respectively, in the DRSS- and PLI-guided arms. NPDR versus PDR eyes at baseline achieved a DRSS improvement of ≥2 steps after a mean 4.9 and 3.6 IAIs (P = .03). Two eyes developed a PDR event at week 52 following 5 months of quiescence.The randomized PRIME study analyzed 2 imaging-based biomarkers to guide PRN management with IAI of DR without DME: DRSS level and PLI. Within the context of this study with limitations, most patients required IAI re-treatment every 3-4 months, and deterioration of PLI appeared to precede DRSS level worsening. Finally, these findings reaffirm the fact that close clinical follow-up is important even among eyes that achieve substantial DRSS improvements with apparently quiescent disease.

To evaluate the effect of intravitreal aflibercept on diabetic retinopathy (DR) severity and visual function in patients with proliferative DR (PDR) without diabetic macular edema (DME).Prospective, longitudinal, multicenter clinical trial.Forty eyes of 40 patients with PDR and no DME were enrolled in this study. Patients were randomized into monthly and quarterly 2-mg aflibercept injection cohorts and were treated over a period of 12 months.All patients underwent ultra-widefield fundus imaging including pseudocolor and fluorescein angiography using an Optos 200Tx device.Severity of DR at baseline, month 6, and month 12 was evaluated using the DR severity scale (DRSS). The DRSS scores were correlated with the 25-item Visual Function Questionnaire (VFQ-25) and 39-item Visual Function Questionnaire (VFQ-39) scores at baseline and month 12.Mean age of the patients was 48.2 years (range, 25-75 years), mean duration of diabetes mellitus was 16.1 years (range, 2-36 years), and median glycated hemoglobin level was 8.8% (IQR, 7.4%-10%). Both monthly and quarterly groups demonstrated a statistically significant regression in DRSS from baseline to month 12 (P0.001). The monthly group demonstrated a statistically significant greater regression of DRSS score at the month 6 visit compared with the quarterly group (P = 0.019). However, the difference between the two groups became statistically insignificant at month 12 visit (P = 0.309). Also no difference was found in mean VFQ-25 and VFQ-39 composite scores between the monthly and quarterly groups at month 12 (P = 0.947 and P = 0.921, respectively). The improvement in mean VFQ-25 and VFQ-39 composite scores at month 12 was correlated significantly with improvement in DRSS score (r = 0.384 and P = 0.039, and r = 0.361 and P = 0.046, respectively).In this study of eyes with PDR without DME, both monthly and quarterly aflibercept injection groups showed significant improvement in DR severity at month 12 compared with baseline. The improvement in DRSS score was associated with an improvement in VFQ-25 and VFQ-39 composite score.

Geographic atrophy (GA) is an advanced form of age-related macular degeneration, a late-onset, complex, genetic degenerative disease of the retina. Multiple environmental and genetic factors have been implicated in the development of GA, a pathology ultimately defined by loss of photoreceptors and the underlying retinal pigment epithelium and choriocapillaris. The personal burden of GA has been documented to have a substantial negative impact on quality of life, with progressive and cumulative loss of visual function each year. Currently, there are no treatments to prevent or slow the development or progression of GA. Multiple genetic and histopathologic studies have implicated dysregulation of the complement cascade in GA pathogenesis, leading to the development of several investigational pharmaceuticals targeting key factors in this inflammatory pathway. Several other biochemical pathways have also been implicated in GA development and progression, such as mitochondrial components, mediators of apoptosis and molecules involved in extracellular matrix remodeling, many of which are also being investigated for their potential value as therapeutic targets for GA treatment. Recent advancements in our understanding of GA pathogenesis and the progression of multiple potential therapeutics into later-stage human clinical trials hold great promise for a clinically effective therapeutic for patients with GA to emerge within the near future.

Purpose To evaluate the real-world utility of the ForeseeHome monitoring device (Notal Vision, Ltd., Tel Aviv, Israel) for the detection of conversion from intermediate age-related macular degeneration (iAMD) to neovascular AMD (nAMD) and to compare with results published by the Home Monitoring of the Eye (HOME) study. Design Retrospective analysis of electronic health records. Participants Eyes prescribed use of the ForeseeHome device across 4 retinal practices in the United States. Methods Usage information was collected from the online ForeseeHome portal for all eyes prescribed the device. For a predetermined subset of eyes, additional clinical information was collected through chart review and analyzed for clinical utility. Main Outcome Measures Frequency and length of use, number of eyes that used the device, number of eyes that established a baseline measurement, number of eyes that converted to nAMD, and number of alerts. Results Seven hundred seventy-five eyes of 448 patients were prescribed use of the ForeseeHome device. Six hundred forty-nine eyes (83.7%) used the device at least once; among this population, 478 (73.7%) established a baseline measurement. Patients who established a baseline measurement were significantly younger than those who did not (P Conclusions Compared with the prospective HOME study, the utility of the ForeseeHome device in the current analysis of clinical practice application was limited. A meaningful proportion of eyes never used the device or could not establish a baseline measurement. Overall frequency of use was low, and continuous use of the device decreased over time. A need exists for improvement in home monitoring technology for eyes with iAMD at risk of conversion to nAMD.

Purpose To identify biomarkers for predicting response to anti−vascular endothelial growth factor (VEGF) therapy in diabetic macular edema (DME) and evaluate any links between cytokine expression and optical coherence tomography (OCT) phenotype. Design The IMAGINE is a post hoc image analysis and cytokine expression assessment of the Efficacy & Safety Trial of Intravitreal Injections Combined With PRP for CSME Secondary to Diabetes Mellitus (DAVE) randomized clinical trial. Methods Subjects were categorized as anatomical responders or nonresponders, and within the responder group as rebounders and non-rebounders based on quantitative, longitudinal OCT criteria. Retinal layer and fluid features were extracted using an OCT machine-learning augmented segmentation platform. Responders were further sub-classified by rapidity of response. Aqueous concentrations of 54 cytokines were measured at multiple timepoints. Expression was compared between responder groups and correlated with OCT imaging biomarkers. Results Of the 24 eyes studied, 79% were anatomical responders with 38% super responders, 17% early responders, and 25% slow responders. Twenty-one percent were nonresponders. Super responders had increased baseline vascular endothelial growth factor (VEGF) (880.0 pg/mL vs 245.4 pg/mL; P = .012) and decreased monocyte chemotactic protein-1 (MCP-1) (513.3 pg/mL vs 809.5 pg/mL; P = .0.042) concentrations compared with nonresponders. Interleukin-6 (−24.9 pg/mL vs 442.8 pg/mL; P = .032) concentrations increased among nonresponders during therapy. VEGF concentrations correlated with central subfield thickness (r = 0.49; P = .01). Panmacular retinal volume correlated with increased interleuckin-6 (r = 0.47; P = .02) and decreased MCP-1 (r = −0.45; P = .03). Matrix metallopeptidase-1 correlated with subretinal fluid volume (r = 0.50; P = .01). Conclusions OCT imaging biomarkers correlated with both intraocular cytokines and responsiveness to anti-VEGF therapy, which indicated a possible link to underlying pathways and their relevance to DME prognosis. Baseline concentrations of VEGF and MCP-1 are associated with anatomic response to anti-VEGF therapy.

It is unclear whether there are differences in safety and efficacy between pars plana vitrectomy (PPV) alone and PPV with a supplemental scleral buckle (SB; PPV-SB) for the treatment of rhegmatogenous retinal detachment.This meta-analysis aimed to compare the safety and efficacy of these surgical procedures.In this meta-analysis, Ovid MEDLINE, Embase, and Cochrane Library were systematically searched (January 2000-June 2021). The primary outcome was the final best corrected visual acuity (BCVA), whereas the secondary outcomes were reattachment rates and complications. The risk of bias was assessed using the Cochrane risk-of-bias tool for randomized controlled trials (RCTs) and the risk of bias in nonrandomized studies of interventions tool for nonrandomized studies.This study included 15 661 eyes from 38 studies (32 observational studies and 6 RCTs). The median follow-up duration was 6 months. The final BCVA was similar between PPV and PPV-SB (weighted mean difference [WMD], -0.03 logarithm of the minimum angle of resolution [-0.14 to 0.07]; P = 0.55). There was a significant difference in the single-operation success rate (SOSR) (88.2% versus 86.3%; relative risk [RR], 0.97 [0.95-1.00]; P = 0.03), favoring PPV-SB; however, there was no significant difference in the final reattachment rate (RR, 1.00 [0.99-1.01]; P = 0.56). Pars plana vitrectomy required a significantly higher number of operations to achieve final anatomical reattachment (WMD, 0.13 [0.02-0.24]; P = 0.02). In terms of complications, PPV was significantly less likely to be associated with macular edema (RR, 0.47 [0.25-0.88]; P = 0.02) and epiretinal membrane formation (RR, 0.70 [0.52-0.94]; P = 0.02), but these differences were no longer significant in studies published after 2010 or in RCTs. Significant proliferative vitreoretinopathy, lens status, and macular attachment status did not mediate differences in these effects.There were no significant differences in the final visual acuity outcomes between PPV and PPV-SB. Pars plana vitrectomy with supplemental SB was associated with a greater SOSR than standalone PPV, although the magnitude of the effect was small, with a high number needed to treat. The final reattachment rate was similar. In recent studies and in RCTs, the risk of complications was similar between the procedures.

The prospective PRIME trial applied real-time, objective imaging biomarkers to determine individualized retreatment needs with intravitreal aflibercept injections (IAI) among eyes with diabetic retinopathy (DR). 40 eyes with nonproliferative or proliferative DR without diabetic macular edema received monthly IAI until a DR severity scale (DRSS) level improvement of ≥2 steps was achieved. Eyes were randomized 1:1 to DRSS- or PLI- guided management. At the final 2-year visit, DRSS level was stable or improved compared to baseline in all eyes, and mean PLI decreased by 11% (p = 0.73) and 23.6% (p = 0.25) in the DRSS- and PLI-guided arms. In both arms, the percent of pro re nata (PRN) visits requiring IAI was significantly higher in year 2 versus 1 (p &lt, 0.0001). The percent of PRN visits receiving IAI during year 1 was significantly correlated with the percent of PRN visits with IAI during year 2 (p &lt, 0.0001). Through week 104, 77.4% of instances of DRSS level worsening in the DRSS-guided arm were preceded by or occurred alongside an increase of PLI. Overall, consistent IAI re-treatment interval requirements were observed longitudinally among individual patients. Additionally, PLI increases appeared to precede DRSS level worsening, highlighting PLI as a valuable biomarker in the management of DR.

Purpose Explore the spectrum of clinical manifestations of pentosan polysulfate sodium (PPS) maculopathy observed across a range of practice settings. Design Multi-institutional retrospective study. Participants Patients exhibiting findings suggestive of PPS maculopathy identified from April 30, 2019, to December 4, 2020. Methods Members of the Macula Society submitted cases of presumed PPS maculopathy for consideration in this series. Diagnosis was confirmed by masked review of fundus imaging. Clinical characteristics of confirmed cases were summarized with descriptive statistics. Main Outcome Measures Pentosan polysulfate exposure characteristics and fundus imaging features. Results There were 74 patients with PPS maculopathy included in the current study. Median (interquartile range) age at diagnosis was 62.0 years (56.0–65.8). The median duration of exposure to PPS was 14.0 years (10.2–18.9), with a median cumulative exposure of 1.5 kg (0.9–2.4). The most common presenting symptom was decreased or blurry vision (66.2%), followed by prolonged dark adaption or nyctalopia (32.4%). The most common referral diagnosis was age-related macular degeneration (54.1%); 16.2% of patients were referred for suspected PPS maculopathy. Novel imaging findings emerged, including highly asymmetric disease in 2 patients and a prominent vitelliform maculopathy in 2 patients. Conclusions Most patients with PPS maculopathy exhibit characteristic findings on multimodal fundus imaging in the setting of high cumulative exposure to the oral drug. Some patients in the current study manifested novel imaging findings, expanding our understanding of the phenotypic spectrum of this condition. We recommend considering standardized ophthalmic screening of patients treated with PPS.

To assess the efficacy of a treat-and-extend strategy with intravitreal ranibizumab for radiation-related macular edema.Forty eyes with radiation-induced macular edema and decreased visual acuity were enrolled in the phase IIb, prospective clinical trial and randomized into 3 cohorts: (A) monthly ranibizumab, (B) monthly ranibizumab with targeted retinal photocoagulation (TRP), or (C) as-needed ranibizumab and TRP. In year 2, all subjects entered a treat-and-extend protocol for ranibizumab. The primary outcome measure was mean change in early treatment diabetic retinopathy study (ETDRS) best-corrected visual acuity (BCVA) from baseline.Through year 1, the mean change in ETDRS BCVA was significantly different between the three cohorts (p 0.001); cohort A saw the largest gain with + 4.0 letters. Significant anatomic improvements were also seen in all cohorts. Comparatively, through year 2, cohorts A, B, and C had a mean change in ETDRS BCVA of - 1.9, - 3.9, and + 1.3 letters, respectively; additionally, no significant differences were found in absolute ETDRS BCVA across time (ANOVA, p = 0.123). Overall, 90% of eyes maintained VA 20/200 or better and 33.3% of subjects gained at least one line of vision. There were no significant differences in mean central macular thickness for any cohort compared to baseline (p = 0.09). The presence of retinal hemorrhage and intraretinal exudates stayed consistent from year 1 to year 2 for all cohorts.Among eyes with radiation-related macular edema, a treat-and-extend regimen with ranibizumab may not result in as many visual and anatomic improvements as monthly injections. However, treat-and-extend still may prevent serious visual complications compared to historical controls.ClinicalTrials.gov Identifier: NCT02222610.

Since the Collaborative Ocular Melanoma Study (COMS) reported similar mortality rates between enucleation and plaque brachytherapy for patients with medium-sized choroidal melanoma, radiation plaques have become the standard method of treatment for uveal melanoma. However, enucleation remains a valid primary treatment technique in some cases of melanoma with specific surgical indications, risks, and benefits. Today, most physicians evaluate the size and location of the tumor, the presence of extrascleral extensions, feasibility of vision retention, and patient preference when deciding between surgical options, although controversy remains regarding the best treatment course for small- and large-sized tumors. In recent years, genetic profiling has also become an important factor in deciding metastatic risk in uveal melanoma, and fine needle aspiration biopsy is now an important step in assessing melanoma prognosis.

Plaque brachytherapy and other radiation treatments have become an increasingly popular option for primary treatment of uveal melanoma since the publication of results from the Collaborative Ocular Melanoma Study. Radiation therapy, however, can cause direct or indirect damage to important ocular structures outside of the tumor, especially to the lens, retina, and optic nerve. Recent advancements in plaque brachytherapy technology have allowed for the reduction of iatrogenic injury, though some radiation damage is still unavoidable and follow-up treatment options are limited. Before treating with plaque brachytherapy or other radiation options, physicians must evaluate tumor- and patient-level risk factors for extensive radiation damage and discuss the risks and benefits of such a treatment with patients. In the years following radiation therapy for uveal melanoma, patients should also be followed closely by an ophthalmologist to assess for the delayed onset of radiation damage.

Purpose To determine the proportion of patients with proliferative diabetic retinopathy (PDR) who were counted as loss to follow-up (LTFU) patients and to investigate predictive factors. Design Retrospective cohort study. Methods Information was collected for 4,423 patients with PDR between April 30, 2012, and April 30, 2017. Two definitions of LTFU were used. Complete LTFU referred to the population who never returned to care within the study period. Interval LTFU referred to the population who did not adhere to clinical recommendations and missed scheduled appointments, resulting in intervals longer than 6 months or 1 year between 2 appointments. Age, average gross income, and insurance were assessed as potential predictors of interval LTFU. Results Among 4,423 patients with PDR, 2,407 (54.4%) and 2,320 (52.4%) were complete LTFU at 6 months and 1 year, respectively; 782 (17.7%) and 468 (10.6%) patients were interval LTFU for 6 months and 1 year, respectively. Age and average gross income were not found to be significant predictors of interval LTFU. Compared to self-pay, government and private insurance patients were more likely to be interval LTFU at 6 months (government, P = .035; private, P = .005). Private insurance patients were also more likely to be interval LTFU at 1 year (P = .003). Conclusions The identified complete LTFU rates were notably high and warrant further study. More than 1 of 6 patients were interval LTFU for at least 6 months, and 1 of 10 patients was interval LTFU for more than 1 year. Insurance status was significant in determining interval LTFU status. Consistent with other analyses, these results indicate that compliance with clinical appointments among patients with PDR is a substantial clinical challenge.

Recent studies have demonstrated a strong relationship between aging-associated reductions in mitochondrial function, dysregulated intracellular lipid metabolism, and insulin resistance. Given the important role of the AMP-activated protein kinase (AMPK) in the regulation of fat oxidation and mitochondrial biogenesis, we examined AMPK activity in young and old rats and found that acute stimulation of AMPK-alpha(2) activity by 5'-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) and exercise was blunted in skeletal muscle of old rats. Furthermore, mitochondrial biogenesis in response to chronic activation of AMPK with beta-guanidinopropionic acid (beta-GPA) feeding was also diminished in old rats. These results suggest that aging-associated reductions in AMPK activity may be an important contributing factor in the reduced mitochondrial function and dysregulated intracellular lipid metabolism associated with aging.

We previously identified two inbred mouse strains, C57BL/6J and CASA/Rk, with different plasma plant sterol levels. An intercross between these strains revealed a broad plasma plant sterol locus on chromosome 14, which peaked at 17 centimorgan (cM) with a maximum logarithm of the odds score of 9.9. Studies in a chromosome 14 congenic strain, 14KK, with a 4–60 cM CASA/Rk interval on the C57BL/6J background revealed that males, but not females, had decreased plasma plant sterol levels and intestinal cholesterol absorption. In two subcongenic strains, 14PKK and 14DKK, with 4–19.5 and 19.5–60 cM CASA/Rk intervals, respectively, both males and females had decreased plasma plant sterol levels and decreased intestinal cholesterol absorption. Compatible with the decreased plasma plant sterol phenotype, 14PKK mice had increased biliary plant sterol excretion, whereas 14DKK mice did not. Therefore, gender-dependent interactions of genes at the 14PKK and 14DKK intervals are likely to underlie the 14KK interval effect on plasma plant sterol levels and sterol absorption from the intestine. These studies confirm the plasma plant sterol locus on mouse chromosome 14 and provide evidence that there are at least two sets of genes operating: one set affecting intestinal sterol absorption and biliary excretion, and the other set mainly affecting intestinal sterol absorption.

An intercross between C57BL/6J and CASA/Rk mice was used to study the genetics of biliary bile acid composition. In parental strains, male C57BL/6J mice had significantly higher cholic acid (CA; 14%) and lower beta-muricholic acid (betaMC; 27%) than CASA/Rk mice, whereas females did not differ. However, quantitative trait locus analysis of F2 mice revealed no significant chromosome 9 loci in males but loci in females on chromosome 9 for percentage CA (%CA) at 72 centimorgan (cM) [logarithm of the odds (LOD) 5.89] and %betaMC at 54 cM (LOD 4.09). Chromosome 9 congenic and subcongenic strains representing CASA/Rk intervals 38-73 cM (9KK) and 68-73 cM (9DKK) on the C57BL/6J background were made. In 9KK and 9DKK males, %CA was increased and %betaMC was unchanged, whereas in 9KK but not 9DKK females, %CA was increased and %betaMC was decreased. Sterol 12alpha-hydroxylase (Cyp8b1) channels bile acid precursors into CA and maps at chromosome 9 (73 cM). However, there was no significant difference in Cyp8b1 mRNA or enzymatic activity between parental mice, parental-congenic-subcongenic mice, or high-low biliary %CA F2 mice. In summary, two chromosome 9 loci control sexually dimorphic effects on biliary bile acid composition: a distal (68-73 cM) major determinant in males, and a more proximal (38-68 cM) major determinant in females. In this intercross, Cyp8b1, a strong candidate, does not appear to be responsible.

Screening of 932 adults on the Pacific island of Kosrae for plasma plant sterol levels disclosed three subjects, two of them asymptomatic, with phytosterolemia. Sequencing the ATP binding cassette subfamily G member 8 (ABCG8) gene revealed a novel exon 2 mutation that causes a change in codon 24 from glutamine to histidine and a frame shift followed by a premature stop codon, precluding the formation of a functional ABCG8 protein. Genotyping of 1,090 Kosraens revealed 150 as carriers, a 13.8% carrier rate. DNA sequencing of 67 carriers revealed the same mutation as in the probands. In carriers, plasma campesterol and sitosterol levels were 55% and 30% higher, respectively, than in noncarriers. Moreover, compared with noncarriers, carriers showed 21% lower plasma levels of lathosterol, a surrogate marker for cholesterol biosynthesis. There was no difference between the groups in plasma total cholesterol, triglycerides, apolipoprotein B, or apolipoprotein A-I levels. In summary, on the island of Kosrae, a strong founder effect of a mutant ABCG8 allele results in a large number of carriers with increased plasma plant sterol levels and decreased lathosterol levels. The latter finding suggests that heterozygosity for a mutated ABCG8 allele results in a modest increase in dietary cholesterol absorption and a decrease in cholesterol biosynthesis.

Plasma non-HDL and HDL cholesterol levels are predictors of cardiovascular diseases. We carried out a genetic cross between two laboratory inbred mouse strains, C57BL/6J and CASA/Rk, to detect loci that control the plasma levels of non-HDL and HDL cholesterol. With regard to non-HDL cholesterol, chow-fed CASA/Rk males and females had 87% and 25% higher levels, respectively, than did C57BL/6Js. The levels of non-HDL cholesterol in F1s were similar to C57BL/6J. There was no strain difference in HDL cholesterol levels. An intercross between F1s was performed, and plasma non-HDL and HDL cholesterol was measured in 185 male and 184 female mice. In both male and female F2 mice, plasma non-HDL and HDL cholesterol levels were unimodally distributed; however, in both cases the values for females were significantly lower than for males. Therefore, linkage analysis was performed with sex as a covariate. Significant linkage for non-HDL cholesterol was found on chromosome 6 at 49 cM (LOD 5.17), chromosome 4 at 55 cM (LOD 4.22), and chromosome 8 at 7 cM (LOD 3.68). Significant linkage for HDL cholesterol was found on chromosome 9 at 14 cM (LOD 7.52) and chromosome 8 at 76 cM (LOD 4.69). A significant epistatic interaction involving loci on chromosomes 2 and 5 was also observed for non-HDL cholesterol. In summary, linkage analysis in these cross-identified novel loci confirmed previously identified loci in control of plasma non-HDL and HDL cholesterol and disclosed a novel interaction in controlling non-HDL cholesterol levels in the mouse.