This study compares outcomes of initial trabeculectomy with mitomycin C in patients of Hispanic descent with those in patients of European descent and attempts to identify prognostic factors for failure.
Key Points
Question
What are the outcomes of initial trabeculectomy with mitomycin C in patients of Hispanic descent compared with those in patients of European descent?
Finding
In this matched cohort study of 222 eyes, success rates of initial trabeculectomy with mitomycin C were lower in patients of Hispanic descent compared with patients of European descent, according to various success criteria used.
Meaning
These findings highlight the need for better strategies to regulate wound healing following trabeculectomy and highlight the importance of conducting prospective studies with larger cohorts to assess glaucoma surgical outcomes in patients of Hispanic descent.
Abstract
Importance
Previous studies suggest that race or ethnicity may influence glaucoma surgical outcomes.
Objective
To compare outcomes of initial trabeculectomy with mitomycin C (MMC) in patients of Hispanic descent with those in patients of European descent and identify prognostic factors for failure.
Design, Setting, and Participants
This retrospective matched-cohort study was conducted at a single-tertiary academic center. The study included 111 eyes from 96 patients of Hispanic descent that were matched to 111 eyes from 108 patients of European descent, based on age (±5 years), surgeon, lens status, and surgery date (±1 year). Ethnicity was self-determined by patients.
Exposure
Initial trabeculectomy with MMC.
Main Outcome Measures
Criteria A, B, and C defined qualified success as final intraocular pressure (IOP) of 18 mm Hg or less, 15 mm Hg or less, and 12 mm Hg or less, respectively, with corresponding IOP reduction of 20% or more, 25% or more, and 30% or more, or a decrease of 2 or more medications. Complete success required meeting the above criteria without medication use. Kaplan-Meier survival curves compared patients of Hispanic descent and patients of European descent success rates with log-rank tests. Cox proportional hazard models estimated the influence of ethnicity on surgical success adjusting for confounders.
Results
The Hispanic descent cohort included 59 females (61.5%) and 37 males (38.5%) with a mean (SD) age of 69.1 (9.9) years. The European descent cohort included 53 females (49.1%) and 55 males (50.9%) with a mean (SD) age of 69.2 (9.4) years. Qualified success rates at 5 years in Hispanic descent and European descent patients were 52% and 68% based on criteria A (difference, 16.7%; 95% CI, 4.0%-29.4%; P < .001), 45% and 61% according to criteria B (difference, 16.2%; 95% CI, 3.2%-29.1%; P = .01), and 31% and 51% based on criteria C (difference, 20.0%; 95% CI, 7.3%-32.6%; P = .002). On multivariable analyses, Hispanic descent was associated with higher failure rates with all complete and qualified success criteria (hazard ratio range, 2.07-3.03; P < .001). Early bleb leaks were more frequent in patients of Hispanic descent (14 eyes vs 6 eyes; P = .10).
Conclusion and Relevance
In this study, Hispanic descent was associated with higher failure rate after initial trabeculectomy with adjunctive MMC compared with European descent. These findings need to be considered when glaucoma surgery is contemplated in patients of Hispanic descent, especially if these findings are confirmed in future studies that address some of the limitations of this single-center retrospective investigation.
Introduction
Glaucoma is a leading cause of irreversible blindness globally and is the primary cause of blindness among the Hispanic and African American populations.1,2,3 Over the past few decades, the prevalence of primary open-angle glaucoma (POAG) among patients of Hispanic descent has been shifting. Early studies from 2001 and 2005 through 2007 reported relatively modest rates of POAG among Hispanic individuals. The Los Angeles Latino Eye Study (LALES) reported especially high POAG prevalence among older adults of Hispanic descent, reaching 16% in those older than 70 years.4,5,6
Earlier studies, such as LALES and Proyecto VER, included populations that were predominantly Mexican American, leaving open the question of whether their findings applied to the broader Hispanic population.7,8,9 More recent studies, such as the Hispanic Community Health Study/Study of Latinos, have expanded their scope to evaluate eye health knowledge and ocular care access in diverse backgrounds in this broad population.10,11,12 Notably, by 2011, Hispanic individuals accounted for approximately 27% of all POAG cases in the US, a figure projected to reach 50% by 2050.13 This trend is primarily driven by demographic factors, such as the growth and aging of this population, along with enhanced disease detection.14,15,16
Numerous studies have explored the racial and ethnic disparities among patients with glaucoma.16,17 Individuals of Hispanic descent are diagnosed with glaucoma at a younger age and the disease is more severe at baseline compared with White patients.16,17 Previous studies have demonstrated that race or ethnicity influences the success rates of trabeculectomy, with individuals of African descent showing a higher susceptibility to surgical failure.18,19,20,21,22 To our knowledge, the outcomes of filtering surgery in Hispanic patients have not been well described in the literature. In this study, we aimed to compare the surgical outcomes of initial trabeculectomy with adjunctive mitomycin C (MMC) in a retrospective cohort of patients of Hispanic descent with glaucoma with a matched cohort of patients of European descent at a tertiary referral center.
Methods
Patient Cohorts
We conducted a retrospective review of the clinical records from the Glaucoma Division at the Stein Eye Institute, University of California Los Angeles (UCLA) between March 1999 and April 2023 to identify all patients of Hispanic descent with glaucoma who underwent initial trabeculectomy with adjunctive MMC with surgery carried out by 1 of 5 attending glaucoma surgeons. The study received approval from the Human Subject Protection Committee and the institutional review board at UCLA. The study was conducted in compliance with the principles of the Declaration of Helsinki and the Health Insurance Portability and Accountability Act, and followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guidelines. Informed consent was not required due to the study’s retrospective design and the minimal risk involved.
Ethnicity was determined through self-identification based on UCLA’s standardized check-in questionnaire. Patients were first asked to identify as either Hispanic/Latino or non-Hispanic, followed by a question on race with options including African American, Asian, White, and other/2 or more. We included only those who self-identified exclusively as Hispanic (Latino) in the Hispanic descent cohort and those self-identified as non-Hispanic White in the European descent cohort, excluding individuals who selected other or more than 1 racial and ethnic category. No patients in our dataset reported multiple racial or ethnic identities. The enrolled patients met the following criteria: self-identified as either of Hispanic or European descent, trabeculectomy as the initial incisional glaucoma surgery with adjunctive MMC, diagnosis of POAG, primary angle-closure glaucoma, pseudoexfoliative glaucoma, pigmentary glaucoma, or normal-tension glaucoma, and a minimum follow-up of 3 months (2 eyes in the Hispanic cohort were excluded due to follow-up less than 3 months). Eyes with a history of prior conjunctival surgery or simultaneous cataract extraction were excluded. A total of 111 eyes of 96 patients of Hispanic descent met the inclusion criteria and were matched based on age (within a 5-year age range), lens status (phakic vs pseudophakic), date of surgery (within 1 year), and surgeon with a cohort of 111 eyes of 108 patients of European descent.
The following data were collected from medical records: demographic characteristics, intraoperative and postoperative findings, baseline ocular features, such as lens status and central corneal thickness, complications until failure, last follow-up, or repeat glaucoma surgery, and visual acuity, intraocular pressure (IOP), number of medications, and clinical findings throughout the follow-up period. The baseline preoperative IOP and number of medications were calculated by averaging the IOP measurements and medication counts from all the visits completed over the 3 months preceding the surgery date. Measurements of the Snellen visual acuity were converted into logMAR equivalent. Bleb leaks were classified as early if they occurred within the first 3 months after surgery and as late if detected 3 or more months after the surgery date.
Surgical Technique
Surgical procedures were performed after either peribulbar or retrobulbar anesthesia. Either a fornix-based or limbus-based conjunctival flap was used, according to the attending physician’s preference. Mitomycin C was applied before or after creation of the scleral flap using multiple sponges soaked in MMC (0.2-0.3 mg/mL). The duration of application (1-3 minutes) was determined by each attending surgeon. The conjunctival flap was closed in a watertight fashion with 9-0 Vicryl sutures.
Success Criteria
Qualified success rate (ie, success rate with or without medications) was the primary outcome measure. The secondary outcome measures were complete success rates (ie, success without the need for medications), IOP, number of medications, postoperative complications, and subsequent glaucoma surgeries. Criteria A, B, and C were used to define success as follows: criteria A, final IOP of 18 mm Hg or less and either 20% or greater reduction in IOP or reduction of at least 2 medications; criteria B, final IOP of 15 mm Hg or less and either 25% or greater reduction in IOP or reduction of at least 2 medications; criteria C, final IOP of 12 mm Hg or less and either 30% or greater reduction in IOP, or reduction of at least 2 medications. The absence of a need for glaucoma medications was required for complete surgical success. Lastly, eyes requiring additional glaucoma surgeries were classified as failures.
Statistical Methods
Continuous variables with Gaussian and non-Gaussian distributions were compared using the unpaired t test and the Wilcoxon signed rank test. The χ2 test was applied to compare categorical variables. The long-term results were compared between the Hispanic descent and European descent cohorts based on the 3 success criteria using the Kaplan-Meier survival analysis and the log-rank test. The precision of the time to failure in a retrospective study somewhat relies on visit intervals, as the intervals between consecutive visits are different. To address this issue, failure was considered to have happened in the middle of the time interval prior to the visit at which the failure was identified. We required confirmation of failure on a subsequent visit except in cases where failure was determined to have occurred at the final visit. We then used Cox proportional hazard regression to identify and adjust for variables predicting surgical failure. The following potential predictors were assessed on univariable analyses: sex, age, ethnicity, family history of glaucoma, history of diabetes or hypertension, baseline IOP, baseline number of medications, central corneal thickness, lens status, baseline visual field mean deviation (MD), fornix-based vs limbus-based conjunctival flap, number of scleral flap sutures, duration of MMC application, and early bleb leaks. Subsequently, multivariable analyses were carried out, including variables clinically shown to impact failure following trabeculectomy or variables with a 2-sided P value less than .20 on univariable analyses. The correlation between the 2 eyes of the same patient was considered using a shared frailty adjustment. After fitting the final multivariate model, smoothed plots of scaled Schoenfeld residuals and log-log plots were reviewed to verify the proportional hazards assumption. All P values were 2-tailed. All statistical analyses were conducted using R version 4.3.2 (R Foundation for Statistical Computing).23
Results
One hundred eleven eyes from 96 patients of Hispanic descent and 111 eyes from 108 patients of European descent were included in the study. Table 1 presents the demographic and clinical characteristics of the 2 cohorts. The mean (SD) age of patients of Hispanic descent was 69.1 (9.9) years compared with 69.2 (9.4) years for patients of European descent. The baseline mean (SD) IOP was 18.7 (7.5) mm Hg in patients of Hispanic descent and 20.0 (7.6) mm Hg in patients of European descent. The mean (SD) number of preoperative glaucoma medications was 3.0 (1.2) and 2.7 (1.0), respectively. The median (IQR) follow-up time was 2.3 (0.83-5.05) years for patients of Hispanic descent and 3.3 (1.8-6.4) years for patients of European descent. The median number of postoperative appointments within the first 3 months was comparable between the 2 cohorts (5 in patients of European descent vs 6 in patients of Hispanic descent; P = .63). Most patients of Hispanic descent (82.9%) and patients of European descent (86.5%) received a 1-minute application of MMC. The baseline visual field mean deviation (MD) was –11.8 (9.1) dB in patients of Hispanic descent and –9.3 (8.5) dB in patients of European descent.
Table 1. Demographic and Clinical Characteristics of the 2 Cohorts of Patients of Hispanic Descent and European Descent .
| Variable | Patients, No. (%) | |
|---|---|---|
| Hispanic descent | European descent | |
| Patient | ||
| No. of patients | 96 | 108 |
| Follow-up time, y, median (IQR) | 2.3 (0.83-5.05) | 3.3 (1.8-6.4) |
| Age, y, mean (SD) | 69.1 (9.9) | 69.2 (9.4) |
| Sex | ||
| Male | 37 (38.5) | 55 (50.9) |
| Female | 59 (61.5) | 53 (49.1) |
| Eye | ||
| No. of eyes | 111 | 111 |
| Eye laterality | ||
| Right | 61 (55.0) | 56 (50.5) |
| Left | 50 (45.0) | 55 (49.5) |
| Glaucoma type | ||
| Primary open-angle | 90 (81.1) | 80 (72.1) |
| Primary angle-closure | 13 (11.7) | 13 (11.7) |
| Pseudoexfoliative | 4 (3.6) | 14 (12.6) |
| Pigmentary | 0 (0) | 1 (0.9) |
| Normal-tension | 2 (1.8) | 3 (2.7) |
| Preoperative lens status | ||
| Phakic | 75 (67.6) | 75 (67.6) |
| Pseudophakic | 36 (32.4) | 36 (32.4) |
| Preoperative IOP, mm Hg, mean (SD) [range] | 18.7 (7.5) [8-46] | 20.0 (7.6) [4-46] |
| No. of preoperative medications, mean (SD) [range] | 3.0 (1.2) [0-6] | 2.7 (1.0) [0-5] |
| Conjunctival flap | ||
| Fornix-based | 89 (80.2) | 98 (88.3) |
| Limbus-based | 22 (19.8) | 13 (11.7) |
| Visual acuity, median (range) | 20/30 (LP-20/20) | 20/30 (HM-20/20) |
| Visual acuity, logMAR, median (range) | 0.2 (3-0) | 0.2 (2-0) |
| Duration of MMC application (0.2-0.3 mg/mL), min | ||
| 1 | 92 (82.9) | 96 (86.5) |
| 2 | 16 (14.4) | 13 (11.7) |
| 3 | 3 (2.7) | 2 (1.8) |
| Baseline VF MD, mean (SD), dB | –11.8 (9.1) | –9.3 (8.5) |
| Family history of glaucoma | 61 (55.0) | 47 (58.0) |
Abbreviations: HM, hand movement; IOP, intraocular pressure; LP, light perception; MD, mean deviation; MMC, mitomycin C; VF, visual field.
Postoperative complications in the 2 cohorts are presented in Table 2. The overall incidence of complications was higher in patients of Hispanic descent compared with patients of European descent (46 eyes [41.4%] vs 29 eyes [26.1%]; P = .02). Early wound leaks were more common than late bleb leaks with 14 eyes of patients of Hispanic descent (12.6%) experiencing early leaks compared with 6 eyes of patients of European descent (5.9%) (P = .10). Late hypotony (IOP less than 6 mm Hg for more than 3 months) was noted in 15 eyes of patients of Hispanic descent (13.5%) and 12 eyes of patients of European descent (13.3%) (P = .68). Other complications, including shallow anterior chambers and bleb encapsulation, occurred more frequently in individuals of Hispanic descent.
Table 2. Complications After Initial Trabeculectomy With Mitomycin C in Patients of Hispanic Descent Compared With Those of European Descent.
| Postoperative complications | Eyes, No. (%) | Difference, % (95% CI) | P value | |
|---|---|---|---|---|
| Hispanic descent (n = 111) | European descent (n = 111) | |||
| All leaks | 17 (15.3) | 9 (8.1) | 7.2 (–1.2 to 15.6) | .14 |
| Early wound leak | 14 (12.6) | 6 (5.4) | 7.2 (–0.2 to 14.6) | .10 |
| Late bleb leak | 6 (5.4) | 3 (2.7) | 2.7 (–2.4 to 7.8) | .49 |
| Fornix-based flap with any leak | 11 (9.9) | 7 (6.3) | 3.6 (–3.5 to 10.7) | .46 |
| Limbus-based flap with any leak | 7 (6.3) | 2 (1.8) | 4.5 (–0.6 to 9.6) | .17 |
| Shallow anterior chamber | 4 (3.6) | 0 (0) | 3.6 (–0.4 to 8.9) | .13 |
| Hypotony (IOP <6 mm Hg for >3 mo) | 15 (13.5) | 12 (10.8) | 2.7 (–5.8 to 11.2) | .68 |
| Encapsulation | 10 (9.1) | 8 (7.2) | 1.8 (–5.3 to 8.9) | .80 |
| Total | 46 (41.4) | 29 (26.1) | 15.3 (3 to 27.5) | .02 |
Abbreviation: IOP, intraocular pressure.
Kaplan-Meier survival curves demonstrate the cumulative probabilities of qualified (Figure 1) and complete (Figure 2) surgical success over the first 5 years of follow-up as the number of remaining eyes in each group became small at that point. Based on criteria A, mean qualified success rates at the first, third, and fifth years of follow-up were 78.7%, 60.6%, and 52.1%, respectively, in patients of Hispanic descent and 82.0%, 71.5%, and 68.8% in patients of European descent (difference at 5 years, 16.7%; 95% CI, 4.0%-29.4%; P < .001) (Figure 1). The mean complete surgical success rates at the first, third, and fifth years of follow-up based on criteria A were 66.3%, 45.6%, and 36.9%, respectively, for patients of Hispanic descent and 76.6%, 56.1%, and 52.3% for patients of European descent (difference at 5 years, 15.4%; 95% CI, 2.4%-28.3%; P = .01) (Figure 2).
Figure 1. Qualified Success.
Kaplan-Meier survival curves display qualified success rates in patients of Hispanic descent and European descent up to 5 years of follow-up.
Figure 2. Complete Success.
Kaplan-Meier survival curves compare complete success rates in patients of Hispanic descent compared with those of European descent up to 5 years of follow-up.
Based on criteria B, mean qualified success rates at the first, third, and fifth years of follow-up were 70.5%, 52.6%, and 45.2%, respectively, for patients of Hispanic descent and 80.7%, 66.1%, and 61.4% for patients of European descent (difference at 5 years, 16.2%; 95% CI, 3.2%-29.1%; P = .01). The mean complete surgical success rates at the first, third, and fifth years of follow-up based on criteria B were 62.7%, 41.4%, and 34.1%, respectively, for patients of Hispanic descent and 75.9%, 56.5%, and 50.9% for patients of European descent (difference at 5 years, 16.8%; 95% CI, 3.9%-26.6%; P = .01).
Based on criteria C, mean (SD) qualified success rates at the first, third, and fifth years of follow-up were 59.7%, 38.1%, and 30.9%, respectively, for Hispanic descent patients and 68.8%, 55.6%, and 50.9% for patients of European descent (difference at 5 years, 20.0%; 95% CI, 7.3%-32.6%; P = .002). The mean (SD) complete surgical success rates at the first, third, and fifth years of follow-up based on criteria C were 54.7%, 30.5%, and 23.1%, respectively, for patients of Hispanic descent and 66.6%, 47.6%, and 42.8% for patients of European descent (difference at 5 years, 19.7%; 95% CI, 7.6%-31.7%; P = .001).
Cox proportional hazards regression analysis was conducted to identify prognostic factors for failure according to various criteria (Table 3). For qualified success, the final multivariable model indicated that Hispanic descent was a risk factor for failure with all 3 criteria. (criteria A: hazard ratio [HR], 1.81; 95% CI, 1.81-5.08, criteria B: HR, 2.68; 95% CI, 1.65-4.33, and criteria C: HR, 2.21; 95% CI, 1.44-3.39). Worse baseline visual field MD was also a risk factor for failure under criteria A (HR, 1.03; 95% CI, 1.01-1.06). Additionally, female sex was found to be a risk factor for failure according to criteria A and B (criteria A: HR, 1.57; 95% CI, 1.02-2.71; criteria B: HR, 1.57; 95% CI, 1.01-2.48; Table 3). For complete surgical success, Hispanic descent was consistently associated with an increased risk of failure across all 3 criteria. The HR for failure for Hispanic descent (compared with being of European descent) was 2.13 (95% CI, 1.39-3.27) for criteria A, 2.16 (95% CI, 1.41-3.31) for criteria B, and 2.07 (95% CI, 1.37-3.13) for criteria C.
Table 3. Multivariable Prognostic Models for Failure After Initial Trabeculectomy With Mitomycin C in 2 Cohorts of Patients of Hispanic Descent and European Descent.
| Prognostic variable | Criteria | |||||
|---|---|---|---|---|---|---|
| A | B | C | ||||
| HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | |
| Qualified success | ||||||
| Hispanic descent (reference: European descent) | 3.03 (1.81-5.08) | <.001 | 2.68 (1.65-4.33) | <.001 | 2.21 (1.44-3.39) | <.001 |
| Sex (reference: male) | 1.66 (1.02-2.7) | .03 | 1.57 (1.00-2.48) | .05 | 1.29 (0.86-1.93) | .21 |
| Baseline visual field MD, /dB | 0.97 (0.94-0.99) | .03 | 0.97 (0.95-1.00) | .10 | 0.98 (0.95-1.00) | .11 |
| Early wound leak | 1.59 (0.71-3.52) | .25 | 1.55 (0.70-3.42) | .27 | 1.39 (0.69-2.79) | .34 |
| Complete success | ||||||
| Hispanic descent (reference: European descent) | 2.12 (1.38-3.26) | <.001 | 2.16 (1.41-3.31) | <.001 | 2.07 (1.37-3.12) | <.001 |
| Sex (reference: male) | 1.42 (0.94-2.14) | .09 | 1.41 (0.94-2.12) | .09 | 1.19 (0.81-1.74) | .37 |
| Baseline visual field MD, /dB | 0.97 (0.95-1.00) | .08 | 0.97 (0.95-1.00) | .09 | 0.98 (0.96-1.00) | .24 |
| Early wound leak | 1.18 (0.56-2.46) | .65 | 1.23 (0.59-2.57) | .57 | 1.20 (0.6-2.39) | .60 |
Abbreviations: HR, hazard ratio; MD, mean deviation.
Discussion
We found that being of Hispanic descent was a strong and consistent predictor of failure of initial trabeculectomy with MMC as compared with being of European descent. Our results demonstrated notable differences in qualified and complete success rates between patients of Hispanic patients and patients of European descent according to all 3 criteria during the 5-year period after surgery. HRs ranged from 2.07 to 3.04, indicating a clinically relevant difference in surgical outcomes between the 2 ethnic groups (2 to 3 times higher failure rates in patients of Hispanic descent). Worse glaucoma damage at the time of surgery consistently predicted higher failure rates across all criteria; a 1 dB decrease in baseline visual field MD (worse MD) was associated with a 2% to 3% increased risk of failure. The total number of complications was higher among patients of Hispanic descent compared with patients of European descent (46 vs 29 eyes; P = .02); this was mostly driven by higher numbers of early leak and bleb encapsulation in patients of Hispanic descent.
The impact of race and ethnicity on trabeculectomy outcomes has been examined in previous studies.24,25 Nguyen et al18 reported that African American patients showed higher failure rates after initial trabeculectomy with MMC compared with patients of European descent. African American individuals were found to have a greater incidence of bleb leaks following initial trabeculectomy with MMC than patients of European descent. Studies assessing trabeculectomy outcomes in Hispanic populations are currently lacking. The 5-year follow-up results from the Fluorouracil Filtering Surgery Study found Hispanic ethnicity to be a risk factor for trabeculectomy failure.19 In another study, Tseng and colleagues26 found that individuals of Hispanic/Latino descent had a higher risk of failure compared with non-Hispanic White individuals (adjusted HR, 1.91, 95% CI, 1.08-3.39) after trabeculectomy performed for neovascular glaucoma. The reasons for the higher failure rates in patients of Hispanic descent are not immediately clear; however, we would speculate that these higher failure rates could be driven by the same factors observed in other patients with darker skin pigmentation. Similar to African American patients, patients of Hispanic descent are at higher risk of keloid formation, which is essentially a manifestation of an exuberant healing response.27,28
Previous studies explored the influence of ethnicity on glaucoma severity at presentation or disease progression. Halawa et al17 found that Hispanic individuals had greater glaucoma severity at presentation compared with White patients. Non-White patients, including patients of Hispanic descent, had worse visual field MD at their initial visit and, despite greater disease severity, underwent fewer visual field tests during follow-up and demonstrated higher rates of disease progression.29 Patients of Hispanic descent have lower utilization rates of medical and surgical treatments for open-angle glaucoma compared with other ethnic groups.30,31 Glaucoma disparities in the Hispanic population are multifaceted. Limited English proficiency is associated with a lower likelihood of medical needs being met.17 Hispanic patients reported lower levels of indirect trust compared with non-Hispanic White populations.32,33,34 Muir and colleagues35 reported that less trust in the eyecare professional was associated with higher rates of glaucoma-related blindness.35
We could not control for certain socioeconomic factors, such as adherence to the follow-up treatment regimen, which could contribute to the disparities observed in surgical outcomes. The follow-up length was somewhat shorter in the patients of Hispanic descent and the Hispanic descent cohort also had mildly worse MD at baseline (–11.8 dB vs –9.3 dB). These findings point to the potential role of social determinants of health in the worse outcomes seen in our study. We speculate that genetic factors might have also played a sizable role in the observed differences.36 The Hispanic descent group also had slightly higher preoperative medication use, which may have led to more inflammation and subsequent early wound leaks, with longer duration of medication use possibly contributing as well.
To our knowledge, our study is the largest to date to specifically address the association of Hispanic ethnicity with lower success rates of trabeculectomy with MMC. Vajaranant et al13 predicted that the population most affected by POAG will shift from non-Hispanic White individuals to patients of Hispanic descent by 2050, with Hispanic or Latino men representing the major US subgroup with POAG by 2035. Moreover, a recent study based on the IRIS Registry showed that patients of Hispanic descent had increased odds of cup-disc ratio progression and poor vision and more frequently needed glaucoma filtering surgery compared with non-Hispanic White patients.37 These findings highlight the growing impact of glaucoma on the Hispanic population, emphasizing the critical need for improving medical and surgical care for this group.
Limitations
Our study has certain limitations. The determination of individuals’ ethnicity relied on self-reported records in hospital charts. Identifying a patient’s race or ethnicity is challenging and most studies addressing race- or ethnicity-related outcomes rely on patient self-identification. The study design was retrospective, inherently subject to selection bias; unknown potential confounding factors may not have been fully accounted for despite matching. The sample size was relatively small and the Hispanic cohort enrolled in this study may not fully represent the diversity within the Hispanic population, as we were unable to identify various subsets within the Hispanic cohort or evaluate outcomes across such subsets. Lastly, Hispanic patients had a higher follow-up loss rate exceeding 50% after the first year.
Conclusions
In conclusion, this study highlights the association of Hispanic ethnicity with lower success rates of initial trabeculectomy with MMC. Our findings demonstrate that patients of Hispanic descent were at a higher risk of surgical failure compared with patients of European descent. Future research ideally should include larger, prospective cohorts to confirm these findings and try to minimize potential biases. Including diverse Hispanic subgroups and assessing socioeconomic factors, such as health care access and follow-up adherence, is crucial for identifying modifiable barriers. Additionally, understanding genetic and biological factors influencing response to filtering surgery in Hispanic patients might lead to more individualized treatment approaches ultimately improving surgical outcomes for this higher-risk group.
eTable 1. Number of eyes that required secondary procedures following initial trabeculectomy with Mitomycin C in patients of Hispanic descent vs. patients of European descent.
eTable 2. Duration and dose of Mitomycin C application for patients of Hispanic descent vs. patients of European descent.
Data sharing statement.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
eTable 1. Number of eyes that required secondary procedures following initial trabeculectomy with Mitomycin C in patients of Hispanic descent vs. patients of European descent.
eTable 2. Duration and dose of Mitomycin C application for patients of Hispanic descent vs. patients of European descent.
Data sharing statement.
