The clinical utility of a glaucoma polygenic risk score in four population-based European-ancestry cohorts.

OBJECTIVE: We used a polygenic risk score (PRS) to identify high-risk groups for primary open-angle glaucoma (POAG) within population-based cohorts. DESIGN: Secondary analysis of four prospective population-based studies. PARTICIPANTS: We included four European-ancestry cohorts: the United States (US) based Nurses' Health Study (NHS), NHS2, and the Health Professionals Follow-up Study, and the Rotterdam Study (RS) in the Netherlands. The US cohorts included female nurses and male health professionals aged 55+ years. The RS included residents aged 45 years or older living in Rotterdam, the Netherlands. METHODS: PRS weights were estimated by applying the Lassosum method on imputed genotype and phenotype data from the UK-Biobank. This resulted in 144,020 variants, single nucleotide polymorphism (SNPs) and indels, with non-zero betas that we used to calculate a PRS in the target populations. Using multivariable Cox proportional hazard models, we estimated the relationship between the standardized PRS and relative risk for POAG. Additionally, POAG prediction was tested by calculating these models' concordance (Harrell's C-statistic). Finally, we assessed the association between PRS tertiles and glaucoma-related traits. MAIN OUTCOME MEASURES: The relative risk for POAG and Harrell's C-statistic (the equivalent of an area-under-the-curve for longitudinal models). RESULTS: Among 1,046 cases and 38,809‬ controls, the relative risk (95% confidence interval) for POAG for participants in the highest PRS quintile was 3.99 (3.08, 5.18) in the US cohorts, and 4.89 (2.93, 8.17) in the Rotterdam Study, compared with participants with median genetic risk (3rd quintile). In restricted cubic spline analyses, the relation between continuous PRS and POAG risk increased exponentially in the US and Rotterdam cohorts (Pspline<0.05). Combining age, sex, intraocular pressure >25 mmHg, and family history resulted in a meta-analyzed concordance of 0.75 (0.73, 0.75). Adding the PRS to this model improved the concordance to 0.82 (0.80, 0.84). In a meta-analysis of all cohorts, cases in the highest tertile had a larger cup-disc ratio at diagnosis, by 0.11 (0.07, 0.15), and a 2.07-fold increased risk of requiring glaucoma surgery (1.19, 3.60). CONCLUSIONS: Incorporating a PRS into a POAG predictive model improves identification concordance from 0.75 up to 0.82, supporting its potential for guiding more cost-effective screening strategies.

Transformer-Based Deep Learning Prediction of 10-Degree Humphrey Visual Field Tests From 24-Degree Data.

Purpose: To predict 10-2 Humphrey visual fields (VFs) from 24-2 VFs and associated non-total deviation features using deep learning. Methods: We included 5189 reliable 24-2 and 10-2 VF pairs from 2236 patients, and 28,409 reliable pairs of macular OCT scans and 24-2 VF from 19,527 eyes of 11,560 patients. We developed a transformer-based deep learning model using 52 total deviation values and nine VF test features to predict 68 10-2 total deviation values. The mean absolute error, root mean square error, and the R2 were evaluation metrics. We further evaluated whether the predicted 10-2 VFs can improve the structure-function relationship between macular thinning and paracentral VF loss in glaucoma. Results: The average mean absolute error and R2 for 68 10-2 VF test points were 3.30 ± 0.52 dB and 0.70 ± 0.11, respectively. The accuracy was lower in the inferior temporal region. The model placed greater emphasis on 24-2 VF points near the central fixation point when predicting the 10-2 VFs. The inclusion of nine VF test features improved the mean absolute error and R2 up to 0.17 ± 0.06 dB and 0.01 ± 0.01, respectively. Age was the most important 24-2 VF test parameter for 10-2 VF prediction. The predicted 10-2 VFs achieved an improved structure-function relationship between macular thinning and paracentral VF loss, with the R2 at the central 4, 12, and 16 locations of 24-2 VFs increased by 0.04, 0.05 and 0.05, respectively (P < 0.001). Conclusions: The 10-2 VFs may be predicted from 24-2 data. Translational Relevance: The predicted 10-2 VF has the potential to improve glaucoma diagnosis.

Impact of Demographics on Regional Visual Field Loss and Deterioration in Glaucoma.

Purpose: To elucidate the impact of demographics, including gender, race, ethnicity, and preferred language, on regional visual field (VF) loss and progression in glaucoma. Methods: Multivariable linear mixed regressions were performed to determine the impact of race, ethnicity, and preferred language on regional VF loss with adjustment for age and gender. Regional VF loss was defined by pointwise total deviation values and VF loss patterns quantified by an unsupervised machine learning method termed archetypal analysis. All cross-sectional and longitudinal analyses were performed both without and with adjustment for VF mean deviation, which represented overall VF loss severity. P values were corrected for multiple comparisons. Results: All results mentioned had corrected P values less than 0.05. Asian and Black patients showed worse pointwise VF loss than White patients with superior hemifield more affected. Patients with a preferred language other than English demonstrated worse pointwise VF loss than patients with English as their preferred language. Longitudinal analyses revealed Black patients showed worse VF loss/year compared to White patients. Patients with a preferred language other than English demonstrated worse VF loss/year compared to patients preferring English. Conclusions: Blacks and non-English speakers have more severe VF loss, with superior hemifield being more affected and faster VF worsening. Translational Relevance: This study furthered our understanding of racial, ethnic, and socioeconomic disparities in glaucoma outcomes. Understanding the VF loss burden in different racial, ethnic, and socioeconomic groups may guide more effective glaucoma screening and community outreach efforts. This research could help reduce vision loss and improve quality of life in disproportionately affected populations by guiding public health efforts to promote glaucoma awareness and access to care.

Implementation and Consensus.

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Cross-sectional study of cognitive impairment and visual impairment among the elderly population in residential care in India: the Hyderabad Ocular Morbidity in Elderly Study (HOMES).

OBJECTIVE: To report the relationship between visual impairment (VI) and cognitive impairment (CI) among the older population living in residential care homes in Hyderabad, India. STUDY DESIGN: Cross-sectional study. SETTING: 41 homes for the aged centres in the Hyderabad region. PARTICIPANTS: 965 participants aged ≥60 years from homes for the aged centres. PRIMARY OUTCOME MEASURES: Visual impairment and cognitive impairment. METHODS: The Hindi mini-Mental Status Examination (HMSE) questionnaire was used to assess the cognitive function. The final HMSE score was calculated after excluding vision-dependent tasks (HMSE-VI). A detailed eye examination was conducted, including visual acuity (VA) measurement for distance and near vision, using a standard logarithm of the minimum angle of resolution chart under good illumination. CI was defined as having a HMSE-VI score of ≤17. VI was defined as presenting VA worse than 6/12 in the better-seeing eye. Near VI (NVI) was defined as binocular presenting near vision worse than N8 and distance VA of 6/18 or better in the better-seeing eye. Multiple logistic regression was done to assess the association between VI and CI. RESULTS: The mean age (±SD) was 74.3 (±8.3) years (range: 60-97 years). There were 612 (63.4%) women, and 593 (61.5%) had a school education. In total, 260 (26.9%; 95% confidence intervals: 24.2 to 29.9) participants had CI. The prevalence of CI among those with VI was 40.5% compared with 14.6% among those without VI (p<0.01). The logistic regression analysis showed that the participants with VI for distance vision had three times higher odds of having CI (OR 3.09; 95% confidence intervals: 2.13 to 4.47; p<0.01). Similarly, participants with NVI had two times higher odds of having CI (OR 2.11; 95% confidence intervals: 1.36 to 3.29; p<0.01) after adjusting for other covariates. CONCLUSIONS: CI was highly prevalent among those with distance and near VI. VI was independently and positively associated with CI after adjusting for potential confounders. Interventions can be planned to address VI in this vulnerable population which could have a ripple effect in preventing cognitive decline.

Derangement in Nicotinamide Adenine Dinucleotide Metabolism is Observed During Acute Kidney Injury Among Male Agricultural Workers at Risk for Mesoamerican Nephropathy.

Introduction: Mesoamerican nephropathy (MeN) is a chronic kidney disease (CKD) which may be caused by recurrent acute kidney injury (AKI). We investigated urinary quinolinate-to-tryptophan ratio (Q/T), a validated marker of nicotinamide adenine dinucleotide (NAD+) biosynthesis that is elevated during ischemic and inflammatory AKI, in a sugarcane worker population in Nicaragua with high rates of MeN. Methods: Among 693 male sugarcane workers studied, we identified 45 who developed AKI during the harvest season. We matched them 1:1 based on age and job category with 2 comparison groups: (i) "no kidney injury," active sugarcane workers with serum creatinine (sCr) <1.1 mg/dl; and (ii) "CKD," individuals no longer working in sugarcane due to their CKD, who had additional 1:1 matching for sCr. We measured urine metabolites using liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) and compared Q/T and other metabolic features between the AKI and comparison groups. Results: Urine Q/T was significantly higher in workers with AKI than in those with no kidney injury (median interquartile Range [IQR]: 0.104 [0.074-0.167] vs. 0.060 [0.045-0.091], P < 0.0001) and marginally higher than in workers with CKD (0.086 [0.063-0.142], P = 0.059). Urine levels of the NAD+ precursor nicotinamide were lower in the AKI group than in comparison groups. Conclusion: Workers at risk for MeN who develop AKI demonstrate features of impaired NAD+ biosynthesis, thereby providing new insights into the metabolic mechanisms of injury in this population. Therapeutic use of oral nicotinamide, which may ameliorate NAD+ biosynthetic derangement and fortify against kidney injury, should be investigated to prevent AKI in this setting.

Stabilization of ß-Catenin Directs HEB to Limit Thymic Selection.

Activation of ß-catenin in CD4+CD8+ double-positive (DP) thymocytes halts development before the thymic selection stage and predisposes to transformation. Leukemogenesis, but not the developmental block, depends on TCF-1, ß-catenin's DNA-binding partner. In this study, we show that ß-catenin activation directs the DNA-binding protein HEB to block DP thymocyte development. Conditional loss of HEB in DP thymocytes with stabilized ß-catenin restores the frequencies of postselection TCRßhi/CCR7+ and TCRßhi/CD69+ DPs and their cell-cycle profile. This recovery is associated with significant reversal of ß-catenin-induced expression changes, particularly those related to the CD69+ DP cell signature and to cell-cycle pathways. Stabilizing ß-catenin in DP thymocytes directs HEB binding to ≈11,000 novel DNA sites throughout the genome. Novel HEB sites mark most CD69+ DP cell signature genes that change expression upon activation of ß-catenin and then revert after loss of HEB. Moreover, many of the novel HEB sites occupy promoter regions of genes enriched in mitotic cell cycle pathways. HEB binding to those regions correlates with downregulation of the associated genes, and HEB inactivation restores expression to physiologic levels. These findings highlight a molecular interplay between HEB and ß-catenin that can impair thymic development.

Use of Diagnostic Codes for Primary Open-Angle Glaucoma Polygenic Risk Score Construction in Electronic Health Record-Linked Biobanks.

PURPOSE: Polygenic risk scores (PRSs) likely predict risk and prognosis of glaucoma. We compared the PRS performance for primary open-angle glaucoma (POAG), defined using International Classification of Diseases (ICD) codes vs manual medical record review. DESIGN: Retrospective cohort study. METHODS: We identified POAG cases in the Mount Sinai BioMe and Mass General Brigham (MGB) biobanks using ICD codes. We confirmed POAG based on optical coherence tomograms and visual fields. In a separate 5% sample, the absence of POAG was confirmed with intraocular pressure and cup-disc ratio criteria. We used genotype data and either self-reported glaucoma diagnoses or ICD-10 codes for glaucoma diagnoses from the UK Biobank and the lassosum method to compute a genome-wide POAG PRS. We compared the area under the curve (AUC) for POAG prediction based on ICD codes vs medical records. RESULTS: We reviewed 804 of 996 BioMe and 367 of 1006 MGB ICD-identified cases. In BioMe and MGB, respectively, positive predictive value was 53% and 55%; negative predictive value was 96% and 97%; sensitivity was 97% and 97%; and specificity was 44% and 53%. Adjusted PRS AUCs for POAG using ICD codes vs manual record review in BioMe were not statistically different (P ≥.21) by ancestry: 0.77 vs 0.75 for African, 0.80 vs 0.80 for Hispanic, and 0.81 vs 0.81 for European. Results were similar in MGB (P ≥.18): 0.72 vs 0.80 for African, 0.83 vs 0.86 for Hispanic, and 0.74 vs 0.73 for European. CONCLUSIONS: A POAG PRS performed similarly using either manual review or ICD codes in 2 electronic health record-linked biobanks; manual assessment of glaucoma status might not be necessary for some PRS studies. However, caution should be exercised when using ICD codes for glaucoma diagnosis given their low specificity (44%-53%) for manually confirmed cases of glaucoma.

Evaluation of a Novel Ablative 1940 nm Pulsed Laser for Skin Rejuvenation.

BACKGROUND: Skin rejuvenation is a widely sought-after goal, prompting advancements in laser technology for noninvasive and effective treatments. Ablative lasers, in particular, have evolved to address diverse skin concerns, with fractional ablative lasers offering better-tolerated outcomes. The introduction of a novel ablative Thulium pulsed laser, based on Thulium-doped Yttrium aluminum Perovskite (Tm:YAP) crystal, delivers precise and controlled skin rejuvenation by allowing customization of ablative microcolumns. METHODS: A pilot in vivo study was conducted on the abdominal skin of a live female pig. Using the Laser Team Medical (LTM) prototype laser, treatments were administered with varying coagulation settings (minimal and maximum) and energies (32, 80, 120, and 160 mJ per microcolumn). Biopsies were harvested, fixed, and stained for subsequent analysis. The penetration depth and width of the microcolumns were evaluated. RESULTS: Low coagulation settings produced ablative microcolumns with thermal affected zones of 160 µm width, while high coagulation settings resulted in wider zones of 400-530 µm. The ablation cavities' width was estimated to be less than 100 µm in both settings. The novel 1940 nm pulsed laser demonstrated superior microcolumn properties, offering potential advantages such as shorter downtime and increased efficacy compared to existing fractional ablative lasers. CONCLUSION: This study presents encouraging preliminary results regarding the efficacy and safety of the first ablative 1940 nm pulsed laser. The results show ablative microcolumns thinner than the counterpart devices, showing the device safety and potential higher efficacy along with short downtime. The LTM novel ablative 1940 nm pulsed laser holds immense potential for enhancing skin rejuvenation treatments due to its superior microcolumns properties. The versatility of this laser can open new treatment procedures and may extend to different areas of dermatology.

Fluorescence tracking demonstrates T cell recirculation is transiently impaired by radiation therapy to the tumor.

T cells recirculate through tissues and lymphatic organs to scan for their cognate antigen. Radiation therapy provides site-specific cytotoxicity to kill cancer cells but also has the potential to eliminate the tumor-specific T cells in field. To dynamically study the effect of radiation on CD8 T cell recirculation, we used the Kaede mouse model to photoconvert tumor-infiltrating cells and monitor their movement out of the field of radiation. We demonstrate that radiation results in loss of CD8 T cell recirculation from the tumor to the lymph node and to distant sites. Using scRNASeq, we see decreased proliferating CD8 T cells in the tumor following radiation therapy resulting in a proportional enrichment in exhausted phenotypes. By contrast, 5 days following radiation increased recirculation of T cells from the tumor to the tumor draining lymph node corresponds with increased immunosurveillance of the treated tumor. These data demonstrate that tumor radiation therapy transiently impairs systemic T cell recirculation from the treatment site to the draining lymph node and distant untreated tumors. This may inform timing therapies to improve systemic T cell-mediated tumor immunity.

Cross-sectional study of prevalence and correlates of fear of falling in the older people in residential care in India: the Hyderabad Ocular Morbidity in Elderly Study (HOMES).

OBJECTIVE: To report the prevalence and risk factors for the fear of falling (FOF) among older individuals living in residential care facilities in India. DESIGN: Cross-sectional study. SETTING: Homes for the aged centres in Hyderabad, India. PARTICIPANTS: The study included individuals aged ≥60 years from homes for the aged centres. The participants underwent a comprehensive eye examination in make-shift clinics setup in homes. Trained investigators collected the personal and demographic information of the participants and administered the Patient Health Questionnaire-9 and Hearing Handicap Inventory for Elderly questionnaire in the vernacular language. FOF was assessed using the Short Falls Efficacy Scale. The presence of hearing and visual impairment in the same individual was considered dual sensory impairment (DSI). A multiple logistic regression analysis was done to assess the factors associated with FOF. PRIMARY OUTCOME MEASURE: FOF. RESULTS: In total, 867 participants were included from 41 homes for the aged centres in the analyses. The mean (±SD) age of the participants was 74.2 (±8.3) years (range 60-96 years). The prevalence of FOF was 56.1% (95% CI 52.7% to 59.4%; n=486). The multivariate analysis showed that those with DSI had eleven times higher odds of reporting FOF than those with no impairment (OR 11.14; 95% CI 3.15 to 41.4.) Similarly, those with moderate depression had seven times higher odds (OR 6.85; 95% CI 3.70 to 12.70), and those with severe depression had eight times higher odds (OR 8.13; 95% CI 3.50 to 18.90) of reporting FOF. A history of falls in the last year was also associated with increased odds for FOF (OR 1.52; 95% CI 1.03 to 2.26). CONCLUSION: FOF is common among older individuals in residential care in India. Depression, falling in the previous year and DSI were strongly associated with FOF. A cross-disciplinary approach may be required to address FOF among the older people in residential care in India.

Meeting the transfusion needs of a patient with anti-Ena requires an international effort.

This extraordinary case showcases the identification of a rare anti-Ena specificity that was assisted by DNA-based red blood cell antigen typing and collaboration between the hospital blood bank in the United States, the home blood center in Qatar, the blood center Immunohematology Reference Laboratory, as well as the American Rare Donor Program (ARDP) and the International Society for Blood Transfusion (ISBT) International Rare Donor Panel. Ena is a high-prevalence antigen, and blood samples from over 200 individuals of the extended family in Qatar were crossmatched against the patient's plasma with one compatible En(a-) individual identified. The ISBT International Rare Donor Panel identified an additional donor in Canada, resulting in a total of two En(a-) individuals available to donate blood for the patient.

Manhattan Vision Screening and Follow-up Study (NYC-SIGHT): a nested cross-sectional assessment of falls risk within a cluster randomised trial.

BACKGROUND: To investigate the feasibility of using the Stopping Elderly Accidents, Deaths and Injuries (STEADI) Falls Risk Tool Kit during community-based eye health screenings to assess falls risk of participants enrolled in the Manhattan Vision Screening and Follow-Up Study (NYC-SIGHT). METHODS: Cross-sectional analysis of data from a 5-year prospective, cluster-randomised clinical trial conducted in affordable housing developments in New York City in adults age 40 years and older. Prescreening questions determined whether participants were at risk of falling. STEADI tests classified participants at low, moderate or high risk of falling. Multivariate logistic regression determined odds of falls risk of all enrolled participants. RESULTS: 708 participants completed the eye health screening; 351 (49.6%) performed STEADI tests; mean age: 71.0 years (SD±11.3); 72.1% female; 53.6% Black, non-Hispanic, 37.6% Hispanic/Latino. Level of falls risk: 32 (9.1%) low, 188 (53.6%) moderate and 131 (37.3%) high. Individuals age >80 (OR 5.921, 95% CI (2.383 to 14.708), p=0.000), had blurry vision (OR 1.978, 95% CI (1.186 to 3.300), p=0.009), high blood pressure (OR 2.131, 95% CI (1.252 to 3.628), p=0.005), arthritis (OR 2.29876, 95% CI (1.362 to 3.875), p=0.002) or foot problems (OR 5.239, 95% CI (2.947 to 9.314), p=0.000) had significantly higher odds of falling, emergency department visits or hospitalisation due to falling. CONCLUSION: This study detected a significant amount of falls risk in an underserved population. The STEADI Falls Risk screening questions were easy for eye care providers to ask, were highly predictive of falls risk and may be adequate for referral to occupational health and/or physical therapy.

Natural History and Risk Factors for Glaucoma Progression in Chinese Patients With Normal-Tension Glaucoma.

Purpose: To characterize the natural history of normal-tension glaucoma (NTG) in Chinese patients. Methods: The prospective observational cohort study included patients with untreated NTG with a minimum follow-up of 2 years. Functional progression was defined by visual field (VF) deterioration, while structural progression was characterized by thinning of the retinal nerve fiber layer (RNFL) or ganglion cell inner plexiform layer (GCIPL). Results: Among 84 participants (mean age, 60.5 years; mean deviation, -5.01 decibels [dB]) with newly diagnosed NTG followed for an average of 69.7 months, 63.1% progressed during the observation period. Specifically, 29.8% progressed by VF, and 48.8% progressed by either RNFL or GCIPL. In Cox proportional hazards analysis, disc hemorrhage (hazard ratio [HR], 2.82; 95% confidence interval [CI], 1.48-5.35), female gender (HR, 1.98; 95% CI, 1.08-3.62), and mean IOP during the follow-up period (HR, 1.14 per mm Hg; 95% CI, 1.00-1.31) were significant predictors of glaucomatous progression. Additionally, longer axial length (AL; HR, 0.57 per millimeter; 95% CI, 0.35-0.94) was protective against VF progression faster than -0.50 dB/y, and higher minimum diastolic blood pressure (DBP; HR, 0.96 per mm Hg; 95% CI, 0.92-1.00) was protective against structural progression. Conclusions: Nearly two-thirds of untreated Chinese patients with NTG progressed over an average follow-up of 70 months by VF, RNFL, or GCIPL. Disc hemorrhage, female gender, higher mean IOP, shorter AL, and lower minimum DBP were significant predictors for disease progression.

Visual Impairment and Real-World Home Physical Activity With Home Environment in an Older Population.

Importance: Physical activity levels are lower in visual impairment. However, additional factors, such as home environmental features, which can modify physical activity in this group, are unknown. Objective: To investigate the association between home environment features and home physical activity in patients with visual impairment. Design, Setting, and Participants: This cross-sectional study of clinical patients included participants with glaucoma suspect and primary glaucoma who were 60 years or older with varying degrees of visual field damage. Study participants were recruited from the Johns Hopkins Wilmer Eye Institute Glaucoma Clinic, Baltimore, Maryland, from September 2013 through March 2015. Data were analyzed from December 19, 2022, through December 25, 2022. Main Outcomes and Measures: Total in-home steps taken per day was the primary outcome measure; time in daily home physical activity and nonsedentary activity were secondary outcomes. Results: A total of 153 participants were included in analyses with mean age of 71 (SD, 7.8) years and 71 were female (46%). Sixty percent had more than 1 comorbid illness, about one-third took 5 or more prescription drugs, and median daily home steps were 1137. Median integrated visual field sensitivity was 28 dB. Better-eye median visual acuity in logMAR was 0.05 (20/22 Snellen equivalent). For every 0.1-log unit increment in average measured home lighting, participants took 5% more daily steps (rate ratio [RR], 1.05; 95% CI, 1.00-1.10; P = .04) and had a 3% faster average daily peak cadence (RR, 1.03; 95% CI, 1.01-1.05; P = .01). The average number of nonsedentary activity minutes (RR, 1.04; 95% CI, 1.00-1.07; P = .06), average bout duration (ß = 0.03; 95% CI, 0.00-.07; P = .06), and activity fragmentation (ß = -0.06; 95% CI, -0.13 to 0.00; P = .06) showed associations with home lighting. The number of hazards was not associated with any activity metric (steps: RR, 1.14; 95% CI, 0.96-1.34; P = .13; peak cadence: RR, 1.00; 95% CI, 0.93-1.08; P = .98; and nonsedentary time: RR, 1.11; 95% CI, 0.98-1.26; P = .11), nor was the frequency of hazards. Conclusions and Relevance: In this study, results demonstrated that home environment features, particularly lighting, may influence home activity metrics in older adults with visual impairment. Further prospective studies would be needed to confirm if home modifications can improve at-home activity.

RH genotypes and red cell alloimmunization rates in chronically transfused patients with sickle cell disease: A multisite study in the USA.

BACKGROUND: Red cell alloimmunization remains a challenge for individuals with sickle cell disease (SCD) and contributes to increased risk of hemolytic transfusion reactions and associated comorbidities. Despite prophylactic serological matching for ABO, Rh, and K, red cell alloimmunization persists, in part, due to a high frequency of variant RH alleles in patients with SCD and Black blood donors. STUDY DESIGN AND METHODS: We compared RH genotypes and rates of alloimmunization in 342 pediatric and young adult patients with SCD on chronic transfusion therapy exposed to >90,000 red cell units at five sites across the USA. Genotyping was performed with RHD and RHCE BeadChip arrays and targeted assays. RESULTS: Prevalence of overall and Rh-specific alloimmunization varied among institutions, ranging from 5% to 41% (p = .0035) and 5%-33% (p = .0002), respectively. RH genotyping demonstrated that 33% RHD and 57% RHCE alleles were variant in this cohort. Patients with RHCE alleles encoding partial e antigens had higher rates of anti-e identified than those encoding at least one conventional e antigen (p = .0007). There was no difference in anti-D, anti-C, or anti-E formation among patients with predicted partial or altered antigen expression compared to those with conventional antigens, suggesting that variant Rh on donor cells may also stimulate alloimmunization to these antigens. DISCUSSION: These results highlight variability in alloimmunization rates and suggest that a molecular approach to Rh antigen matching may be necessary for optimal prevention of alloimmunization given the high prevalence of variant RH alleles among both patients and Black donors.