Cascade screening for glaucoma in high-risk family members of African-Caribbean glaucoma patients in an urban population in London

Modern Family: An Ethical Justification for System-Led Contact of Relatives Eligible for Cascade Screening in the United States

BACKGROUND

Though genomic science has rapidly advanced, efforts to demonstrate the population-level utility of genomics have been slow to follow. It has long been argued that the family is an important unit of significance in genomics, yet it has been challenging to address this in clinical care. This is apparent in how hospital administrators and clinicians in the United States typically approach cascade screening, the process of notifying and offering genetic testing to at-risk relatives of a patient with a hereditary condition. The most common notification approach is proband-led contact, in which the index patient is responsible for communicating a health risk to their relatives. This model has been associated with suboptimal outcomes. In contrast, recent research has shown that system-led contact, in which healthcare or public health institutions initiate communication to relatives with the proband's consent, has been associated with increased clinical utility and acceptability.

SUMMARY

With the needs of hospital administrators and clinicians in mind, we revisit normative questions about the appropriate way to notify relatives about their potentially elevated risk of developing an actionable disease. We review evidence demonstrating that system-led direct contact of relatives is feasible and acceptable. We further argue that system-led contact of relatives eligible for cascade screening is ethically justified if these programs are designed with public input, have an opt-out provision, and are implemented for conditions that meet specific criteria which we propose in this article.

KEY MESSAGES

In this article, we emphasize the usefulness of public health ethics frameworks to inform the design of system-led contact programs. Beyond this, we make the case that such programs are necessary to realize the population utility of genomic medicine equitably.

Integrating Genetics in Glaucoma Screening

PRCIS

As additional glaucoma genes are identified and classified, polygenic risk scores will be refined, facilitating early diagnosis and treatment. Ensuring genetic research is equitable to prevent glaucoma blindness worldwide is crucial.

PURPOSE

To review the progress in glaucoma genetics over the past 25 years, including the identification of genes with varying contributions to the disease and the development of polygenic risk scores.

METHODS/RESULTS

Over the last 2 and a half decades, glaucoma genetics has evolved from identifying genes with Mendelian inheritance patterns, such as myocilin and CYP1B1, to the discovery of hundreds of genes associated with the disease. Polygenic risk scores have been developed, primarily based on research in Northern European populations, and efforts to refine these scores are ongoing. However, there is a question regarding their applicability to other ethnic groups, especially those at higher risk of primary open angle glaucoma, like individuals of African ancestry. Glaucoma is highly heritable and family history can be used for cascade clinical screening programs, but these will not be feasible in all populations. Thus, cascade genetic testing using well-established genes such as myocilin may help improve glaucoma diagnosis. In addition, ongoing investigations seek to identify pathogenic genetic variants within genes like myocilin.

CONCLUSIONS

The expanding availability of genetic testing for various diseases and early access to genetic risk information necessitates further research to determine when and how to act on specific genetic results. Polygenic risk scores involving multiple genes with subtle effects will require continuous refinement to improve clinical utility. This is crucial for effectively interpreting an individual's risk of developing glaucoma and preventing blindness.

The Significance of Screening Family Members in Glaucoma: Opportunities and Challenges

PRECIS

This article delves into the imperative of screening family members of patients with glaucoma due to the disease's hereditary nature. It discusses the significant risks faced by first-degree relatives, approaches for identification, and challenges in implementing effective screening strategies. Emphasizing education, targeted campaigns, community involvement, and collaborative healthcare approaches, the article highlights the potential for mitigating undiagnosed glaucoma cases through strategic interventions targeting high-risk individuals.

PURPOSE

This article underscores the importance of screening family members of glaucoma patients, emphasizing the hereditary nature of the disease and the potential for screening to allow for early intervention to help prevent unnecessary vision loss.

METHODS/RESULTS

Glaucoma, affecting over 111.8 million by 2040, is relatively asymptomatic until late in the disease. Genetics predispose to glaucoma, with up to 70% heritability. High-risk individuals, particularly first-degree relatives, exhibit substantially elevated glaucoma risks-up to 22% compared with 2.3% in controls. Family history also correlates with greater disease severity. Identifying high-risk family members through cascade screenings for causative genes or direct examinations during proband visits emerges as efficient strategies. Challenges persist, including slow progression, healthcare accessibility, and ethical dilemmas in implementing family member screening. Challenges extend to the healthcare system, socioeconomic barriers, and familial communication issues. Efforts to educate probands and the public on the hereditary nature of glaucoma are pivotal. Tailored education campaigns, leveraging clinic visits, and community screenings, complemented by optometrist collaboration, form essential strategies.

CONCLUSIONS

Although challenges hinder family member screening, educating probands, targeted patient education, collaborative healthcare approaches, and community involvement offer promising avenues to combat undiagnosed glaucoma cases.

The Assessment of Radial Peripapillary Capillary Vessel Density in Adult Children of Patients With Primary Open Angle Glaucoma

PRCIS

The observed decrease in radial peripapillary capillary vessel density among adult children of individuals with primary open angle glaucoma, in comparison to controls, suggests the possibility of early microvascular alterations in the eyes of these at-risk individuals.

PURPOSE

To compare the radial peripapillary capillary vessel density (RPCVD) and peripapillary retinal nerve fiber layer (RNFL) thickness values of eyes between healthy adults with a maternal or paternal history of primary open angle glaucoma (POAG) and age-matched healthy controls without a family history of POAG.

MATERIALS AND METHODS

RPCVD values and RNFL thicknesses in the peripapillary region and 4 quadrants (superior, inferior, nasal, and temporal) were evaluated using optical coherence tomography angiography among 30 adult children of patients with POAG and 30 age-matched healthy controls without a family history of POAG.

RESULTS

The mean whole image RPCVD (51.6±1.7% vs. 49.8±1.7%, P =0.0006) and average RPCVD (54.7±1.7% vs. 53.2±2.1%, P =0.006) values were significantly lower in the adult children of patients with POAG compared with age-matched healthy controls without a family history of POAG. There was no difference in terms of RNFL thickness values in any region.

CONCLUSION

Despite having similar RNFL thickness values to the control group, the observation of lower RPCVD in the eyes of adult children of POAG patients may indicate potential early vascular alterations. The result of the present study encourages further longitudinal studies to determine the potential importance of the underlying vascular alterations in these high-risk individuals.

Comparative Analysis of Glaucoma Screening Uptake Among First-Degree Relatives After Community-Based and Hospital-Based Approaches

Purpose

Glaucoma is the second leading cause of irreversible blindness globally. Primary open-angle glaucoma (POAG) can be genetically transmitted among first-degree relatives (FDRs). Therefore, screening for glaucoma in FDRs can significantly increase the chances of early detection. This study aimed to evaluate the differences in glaucoma screening uptake among FDRs in community and hospital-based settings and the underlying factors, as well as the prevalence of glaucoma in FDRs.

Patients and Methods

Probands and FDRs who underwent screening were classified into two: community-based (group 1) and hospital-based (group 2). They were invited for screening by Village Health Volunteers and ophthalmic nurses, respectively, using information brochures. The FDRs underwent eye examinations, and those with suspected glaucoma underwent further testing for confirmation.

Results

The response rates of probands were 261 (38.2%) for group 1 and 196 (48.8%) for group 2. The uptake screening of FDRs was 30.1% and 64.5%, respectively. Multivariate analysis identified that female FDRs {odds ratio [OR]=1.64; 95% CI 1.14-2.38} and those aged above 45 years (OR=2.06; 95% CI 1.32-3.21) were more likely to participate. FDRs residing outside Chanthaburi Province were less likely to attend than those within Chanthaburi (OR=0.36;95% CI 0.22-0.58). FDRs related to probands with blindness were more likely to participate (OR=1.69; 95% CI 1.13-2.54), as were FDRs with secondary school education or higher (OR=2.49;95% CI 1.48-4.18). Those receiving both medical and surgical treatment were more likely to participate (OR=2.22;95% CI 1.51-3.25). The prevalence of glaucoma was 8.3%, and 19.2% of screened FDRs were glaucoma suspects.

Conclusion

Group 1 showed a significantly lower screening uptake than Group 2. The factors influencing the uptake of screening by FDRs are gender, age, geographic location, visual acuity of the worse eye in probands, education status of FDRs, and treatment modalities of probands.

Empowering Family Glaucoma Risk Communication Using QR-Code-Mediated Online Intervention

PURPOSE

Attempts at engaging relatives of glaucoma patients in education and screening have had limited success. This study explores the feasibility of an electronic intervention to facilitate direct yet reliable glaucoma risk communication between open-angle glaucoma patients (probands) and their first-degree relatives (FDRs).

DESIGN

Prospective survey and assessment of intervention.

PARTICIPANTS

Fifty adult probands, engaging 140 FDRs.

METHODS

Phase I was an iterative process involving creating a customized website and Quick Response (QR)-code-based intervention designed with input from probands, FDRs of patients, community members, and researchers. In phase II, the intervention was deployed in a clinical setting; this involved recruiting probands who had a smartphone and were willing to use the QR-code to message their FDRs a standard message, including a website link about glaucoma risk in FDRs and the importance of getting examined. Follow-up interviews were conducted with probands 1 to 2 weeks after their clinic visit to assess the impact of the intervention. Demographic data, website analytics, and participant feedback were collected and analyzed.

MAIN OUTCOME MEASURES

Increased awareness of glaucoma risk among FDRs and enhanced discussions.

RESULTS

At the time of the first interview, probands reported that 70% of the FDRs were aware of the probands' glaucoma diagnosis, but only 26% had undergone glaucoma screening. Ninety percent of probands had no issues using the QR-codes. Website analytics recorded 73 visits from 51 distinct internet protocol addresses (IPs). After receiving the standard message, 95% of FDRs followed up with the probands, actively discussing glaucoma. Of the probands, 84% completed the follow-up interview 1 to 2 weeks after enrollment. Fifty-nine percent of the FDRs were reported to have scheduled screening appointments. The collected feedback revealed that 96% of probands found the intervention helpful, fostering glaucoma discussions with their FDRs and improving probands' comfort level in discussing health issues with FDRs from baseline (very comfortable: 88%, comfortable: 8%, neutral: 2%, and very uncomfortable: 2%) to the follow-up interview (very comfortable: 98% and comfortable: 2%).

CONCLUSIONS

This innovative online method of communicating the risk of glaucoma to FDRs of probands prompted and increased the comfort level of familial discussions of glaucoma. More than half of FDRs reported making an appointment to get screened for glaucoma.

FINANCIAL DISCLOSURE(S)

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