Excerpt from the Canadian Ophthalmological Society evidence-based clinical practice guidelines for the management of diabetic retinopathy

Diabetic Disease of the Eye in Canada: Consensus Statements from a Retina Specialist Working Group

Despite advances in systemic care, diabetic disease of the eye (DDE) remains the leading cause of blindness worldwide. There is a critical gap of up-to-date, evidence-based guidance for ophthalmologists in Canada that includes evidence from recent randomized controlled trials. Previous guidance has not always given special consideration to applying treatments and managing DDE in the context of the healthcare system. This consensus statement aims to assist practitioners in the field by providing a spectrum of acceptable opinions on DDE treatment and management from recognized experts in the field. In compiling evidence and generating consensus, a working group of retinal specialists in Canada addressed clinical questions surrounding the four themes of disease, patient, management, and collaboration. The working group reviewed literature representing the highest level of evidence on DDE and shared their opinions on topics surrounding the epidemiology and pathophysiology of diabetic retinopathy and diabetic macular edema; diagnosis and monitoring; considerations around diabetes medication use; strategic considerations for management given systemic comorbidities, ocular comorbidities, and pregnancy; treatment goals and modalities for diabetic macular edema, non-proliferative and proliferative diabetic retinopathy, and retinal detachment; and interdisciplinary collaboration. Ultimately, this work highlighted that the retinal examination in DDE not only informs the treating ophthalmologist but can serve as a global index for disease progression across many tissues of the body. It highlighted further that DDE can be treated regardless of diabetic control, that a systemic approach to patient care will result in the best health outcomes, and prevention of visual complications requires a multidisciplinary management approach. Ophthalmologists must tailor their clinical approach to the needs and circumstances of individual patients and work within the realities of their healthcare setting.

Effectiveness and safety of traditional Chinese medicine for diabetic retinopathy: A systematic review and network meta-analysis of randomized clinical trials

BACKGROUND

Diabetic retinopathy (DR) is currently recognized as one of the most serious diabetic microangiopathies and a major cause of adult blindness. Commonly used clinical approaches include etiological control, microvascular improvement, and surgical intervention, but they are ineffective and have many side effects. Oral Chinese medicine (OCM) has been used for thousands of years to treat DR and is still widely used today, but it is unclear which OCM is more effective for DR.

AIM

To estimate relative effectiveness and safety profiles for different classes of OCMs for DR, and provide rankings of the available OCMs.

METHODS

The search time frame was from the creation of the database to January 2023. RevMan 5.3 and Stata 14.0 software were used to perform the systematic review and Network meta-analyses (NMA).

RESULTS

A total of 107 studies and 9710 patients were included, including 4767 cases in the test group and 4973 cases in the control group. Based on previous studies and clinical reports, and combined with the recommendations of Chinese guidelines for the prevention and treatment of DR, 9 OCMs were finally included in this study, namely Compound Xueshuantong Capsules, Qiming Granules, Compound Danshen Dripping Pills, Hexue Mingmu Tablets (HXMM), Qiju Dihuang Pills (QJDH), Shuangdan Mingmu Capsules (SDMM), Danggui Buxue Decoction (DGBX), Xuefu Zhuyu Decoction and Buyang Huanwu Decoction. When these nine OCMs were analyzed in combination with conventional western medicine treatment (CT) compared with CT alone, the NMA results showed that HXMM + CT has better intervention effect on the overall efficacy of DR patients, HXMM + CT has better effect on improving patients' visual acuity, SDMM + CT has better effect on inhibiting vascular endothelial growth factor, DGBX + CT has better effect on reducing fundus hemorrhage area, HXMM + CT has better effect on reducing fasting blood glucose, and QJDH + CT has better effect on reducing glycated hemoglobin. When there are not enough clinical indicators for reference, SDMM + CT or HXMM + CT treatments can be chosen because they are effective for more indicators and demonstrate multidimensional efficacy.

CONCLUSION

This study provides evidence that combining OCMs with CT leads to better outcomes in all aspects of DR compared to using CT alone. Based on the findings, we highly recommend the use of SDMM or HXMM for the treatment of DR. These two OCMs have demonstrated outstanding efficacy across multiple indicators.

Assessing the feasibility, acceptability, and fidelity of a tele-retinopathy-based intervention to encourage greater attendance to diabetic retinopathy screening in immigrants living with diabetes from China and African-Caribbean countries in Ottawa, Canada: a protocol

BACKGROUND

Diabetic retinopathy is a leading cause of preventable blindness in Canada. Clinical guidelines recommend annual diabetic retinopathy screening for people living with diabetes to reduce the risk and progression of vision loss. However, many Canadians with diabetes do not attend screening. Screening rates are even lower in immigrants to Canada including people from China, Africa, and the Caribbean, and these groups are also at higher risk of developing diabetes complications. We aim to assess the feasibility, acceptability, and fidelity of a co-developed, linguistically and culturally tailored tele-retinopathy screening intervention for Mandarin-speaking immigrants from China and French-speaking immigrants from African-Caribbean countries living with diabetes in Ottawa, Canada, and identify how many from each population group attend screening during the pilot period.

METHODS

We will work with our health system and patient partners to conduct a 6-month feasibility pilot of a tele-retinopathy screening intervention in a Community Health Centre in Ottawa. We anticipate recruiting 50-150 patients and 5-10 health care providers involved in delivering the intervention for the pilot. Acceptability will be assessed via a Theoretical Framework of Acceptability-informed survey with patients and health care providers. To assess feasibility, we will use a Theoretical Domains Framework-informed interview guide and to assess fidelity, and we will use a survey informed by the National Institutes of Health framework from the perspective of health care providers. We will also collect patient demographics (i.e., age, gender, ethnicity, health insurance status, and immigration information), screening outcomes (i.e., patients with retinopathy identified, patients requiring specialist care), patient costs, and other intervention-related variables such as preferred language. Survey data will be descriptively analyzed and qualitative data will undergo content analysis.

DISCUSSION

This feasibility pilot study will capture how many people living with diabetes from each group attend the diabetic retinopathy screening, costs, and implementation processes for the tele-retinopathy screening intervention. The study will indicate the practicability and suitability of the intervention in increasing screening attendance in the target population groups. The study results will inform a patient-randomized trial, provide evidence to conduct an economic evaluation of the intervention, and optimize the community-based intervention.

Effectiveness of Nonmydriatic Ultra-Widefield Retinal Imaging to Screen for Diabetic Eye Disease: A Randomized Controlled Trial (Clearsight)

OBJECTIVE

Suboptimal diabetic eye disease screening is a major cause of preventable vision loss. Screening barriers include mydriasis and the need for dedicated screening appointments. The Clearsight trial assessed whether nonmydriatic ultra-widefield (NM UWF) screening on the day of a diabetes clinic visit improved detection of clinically important eye disease versus usual screening.

RESEARCH DESIGN AND METHODS

This single-center, randomized, parallel-group controlled trial was conducted at St. Joseph's Health Care, London, Ontario, Canada. Adults with diabetes due for screening were randomized to same-day, on-site screening (NM UWF imaging) on the day of a scheduled diabetes clinic visit or usual screening (encouraged to arrange optometrist screening). The primary outcome was detection of actionable eye disease (AED), defined as the need for an ophthalmology referral or increased ocular surveillance. The primary analysis (modified intention-to-screen) compared the proportions of AED between groups within 1 year of enrollment.

RESULTS

Of 740 participants randomized between 7 March 2016 and 17 April 2019, 335 on-site screening and 323 usual screening participants met criteria for the primary analysis. More AED was detected in the on-site screening group than in the usual screening group (50 of 335 [14.9%] vs. 22 of 323 [6.8%]; adjusted odds ratio 2.51; 95% CI 1.49-4.36). The number needed to screen by on-site screening in order to detect 1 additional patient with AED was 13 (95% CI 8-29).

CONCLUSIONS

Same-day, on-site screening by NM UWF imaging increased the detection of clinically important diabetic eye disease versus usual screening. Integration of NM UWF imaging into routine diabetes clinic visits improved screening adherence and has the potential to prevent vision loss.

Mailed Letter Versus Phone Call to Increase Diabetic-Related Retinopathy Screening Engagement by Patients in a Team-Based Primary Care Practice: Prospective, Single-Masked, Randomized Trial

BACKGROUND

Vision loss from diabetic-related retinopathy (DR) is preventable through regular screening.

OBJECTIVE

The purpose of this study was to test different patient engagement approaches to expand a teleophthalmology program at a primary care clinic in the city of Toronto, Canada.

METHODS

A teleophthalmology program was set up in a large, urban, academic, team-based primary care practice. Patients older than 18 years with type 1 or type 2 diabetes were randomized to one of the following 4 engagement strategies: phone call, mail, mail plus phone call, or usual care. Outreach was conducted by administrative staff within the clinic. The primary outcome was booking an appointment for DR screening.

RESULTS

A total of 23 patients in the phone, 28 in the mail, 32 in the mail plus phone call, and 27 in the control (usual care) group were included in the analysis. After the intervention and after excluding patients who said they were screened, 88% (15/17) of patients in the phone, 11% (2/18) in the mail, and 100% (21/21) in the mail and phone group booked an appointment with the teleophthalmology program compared to 0% (0/12) in the control group. Phoning patients positively predicted patients booking a teleophthalmology appointment (P<.001), whereas mailing a letter had no effect.

CONCLUSIONS

Patient engagement to book DR screening via teleophthalmology in an urban, academic, team-based primary care practice using telephone calls was much more effective than patient engagement using letters or usual care. Practices that have access to a local DR screening program and have resources for such engagement strategies should consider using them as a means to improve their DR screening rates.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03927859; https://clinicaltrials.gov/ct2/show/NCT03927859.

Perceptions of a Teleophthalmology Screening Program for Diabetic Retinopathy in Adults With Type 1 and Type 2 Diabetes in Urban Primary Care Settings

OBJECTIVES

Teleophthalmology has improved diabetic retinopathy screening, and should be expanded in urban areas, where most unscreened individuals reside. In this study we explored facilitators and barriers of teleophthalmology in primary care settings in Toronto, Canada.

METHODS

Semistructured interviews were conducted with 7 health-care providers and 7 individuals with diabetes to explore their perspectives of teleophthalmology in urban primary care settings. Interview data were analyzed using interpretive thematic analysis to generate themes.

RESULTS

Six themes were identified. Facilitators included patient-centred implementation, access to teleophthalmology at primary care sites and patients' trust in their providers' recommendations. Barriers included patients' lack of understanding of diabetic retinopathy and the health-care system, providers' lack of interest and the need to streamline administrative processes.

CONCLUSIONS

Although teleophthalmology was well-received by patients, there was limited interest from primary care providers. Strategies for increasing uptake include increasing primary care providers' awareness of teleophthalmology's value in urban centres, improving administrative processes and centralizing patient recruitment.

Diabetic Retinopathy Screening: A Systematic Review of Qualitative Literature

OBJECTIVES

Diabetic retinopathy is a common microvascular complication that leads to vision loss. Despite national and international organizations developing guidelines for diabetic retinopathy screening, patients with diabetes remain unscreened. Our aim was to understand facilitators and barriers influencing diabetic retinopathy screening attendance and to examine factors that promote program success.

METHODS

MEDLINE, Embase, PsycINFO and CINAHL from inception until September 23, 2019 were used for data collection. Studies were included if they were original qualitative research articles, included adults >18 years of age and assessed diabetic retinopathy screening programs or retinopathy screening as a component of a general diabetes care program. A "best-fit" framework synthesis methodology was used for this analysis.

RESULTS

Twenty-nine articles involving 1,433 participants were identified. Six themes of barriers to, and facilitators of, diabetic retinopathy screening were identified, including access to screening, knowledge and information sharing, training and skills competency, service delivery, cultural competency and psychological factors. Cost and competing interests were common barriers to access; lack of knowledge about screening services was also a frequently reported barrier. Both patients and providers identified the need for improved service delivery, especially the referral and follow-up process. Providers recognized the need for additional training, patients enumerated several psychological barriers to screening uptake and cultural considerations were believed to be important, particularly among indigenous communities.

CONCLUSIONS

To improve screening uptake, the identified challenges must be addressed while also reinforcing the facilitators. Furthermore, program administrators could model new and unsuccessful screening programs after the successful ones while also considering local peculiarities.

Reporting of financial conflicts of interest by Canadian clinical practice guideline producers: a descriptive study

BACKGROUND

The producers of clinical practice guidelines (CPGs) may not disclose industry funding in their CPGs. We reviewed Canadian national CPGs to examine the existence and disclosure of industry-related organizational funding in the CPGs, financial conflicts of interest of committee members and organizational procedures for managing financial conflicts of interest.

METHODS

For this descriptive study, we searched the asset map of the Strategy for Patient-Oriented Research Evidence Alliance and the CPG Infobase for CPGs published between Jan. 1, 2016, and Nov. 30, 2018. Eligible guidelines had to have a national focus and either a first-line drug recommendation or a screening recommendation leading to drug treatment. One investigator reviewed all CPG titles to exclude those that were clearly ineligible. Two reviewers independently reviewed all remaining guidelines and extracted data. We analyzed the data descriptively.

RESULTS

We included 21 CPGs: 3 from government-sponsored organizations, 9 from disease or condition interest groups and 9 from medical professional societies. None of the 3 government-sponsored organizations reported industry funding, and none of their committee members disclosed financial conflicts of interest. Among the 18 disease or condition interest groups and medical professional societies, 14 (93%) of the 15 that disclosed funding sources on websites (3 did not disclose) reported organizational funding from industry, but none disclosed this information in the CPGs; 12 (86%) of the 14 with conflict-of-interest disclosure statements in the CPG (4 did not include disclosures) had at least 1 committee member with a financial conflict (mean proportion of committee members with a conflict 56%); and for all 8 CPGs with identifiable chairs or cochairs (chairs or cochairs not reported for 10) at least 1 of these people had a financial conflict of interest. None of the guidelines described a plan to manage organizational financial conflicts of interest.

INTERPRETATION

Canadian CPGs are vulnerable to industry influence through funding of producers of guidelines and through the financial conflicts of interest of committee members. The CPG producers that receive industry funding should disclose organizational financial conflicts in the CPGs, should engage independent oversight committees and should restrict voting on recommendations to guideline panelists who have no financial conflicts.

Identifying gaps in patient access to diabetic screening eye examinations in Ontario: a provincially representative cross-sectional study

OBJECTIVE

Diabetes is the leading cause of acquired blindness in Canadians under the age of 50 years, and diabetic retinopathy affects an estimated 500 000 Canadians. Early identification of retinopathy with screening eye examinations allows for secondary prevention. To understand the need for resource allotment in diabetic screening, we undertook a cross-sectional study of key demographics and geographics of screened and unscreened patients in Ontario.

METHODS

Ontario Health Insurance Plan (OHIP) records were derived from physician and optometry billing, matched with patients aged >19 years with prevalent diabetes between 2011 and 2013. Data were cross-correlated with demographic covariates, including age, sex, income quintile, immigrant status, as well as geographic covariates such as rurality and patient Local Health Integration Network (LHIN).

RESULTS

Of almost 1 146 000 patients included in the analysis, approximately 406 000 were unscreened. Of note, this included 234 000 adults aged 40-64 years. Approximately 818 000 patients with diabetes lived in large cities, and 301 000 (37%) were unscreened. When the City of Toronto was analyzed as an urban area with the highest density of unscreened prevalence, autocorrelation between the percentage of eye examinations among patients with diabetes aged >40 years and low-income revealed that large areas of Toronto Central correlated for low examination rates and low income. The majority (13/22) of Community Health Centres are present in these areas.

CONCLUSIONS

Large cross-sectional population statistics for diabetes prevalence and ophthalmic examinations provides a geographic and socioeconomic profile for populations of middle-aged adults in large urban areas at risk for developing diabetic retinopathy and who might benefit from interventions to improve the rates of screening eye examinations.

An evidence map of clinical practice guideline recommendations and quality on diabetic retinopathy

To present an evidence map for explicating research trends and gaps, we systematically review clinical practice guidelines (CPGs) on diabetic retinopathy (DR) and assess the quality of CPGs and consistency of recommendations. A literature search was performed in PubMed, Embase, Web of Science, CPG databases, and website of diabetes society to include the CPGs. The basic information, methodological quality, and reporting quality of CPGs, recommendations for DR were exacted by the Excel 2013. Methodological and reporting quality of DR CPGs were evaluated by AGREE II instrument and RIGHT checklist. The bubble plot format of evidence map was made by Excel 2013. Nineteen CPGs proved eligible, which included eight DR CPGs and 11 comprehensive diabetic CPGs. The identified CPGs were of mixed quality and they scored poorly in the rigor of development, applicability domains by AGREE II. Field two (background) had the highest reporting rate (86.31%) and field five (review and quality assurance) obtained the lowest reporting rate (31.58%) among the seven domains of RIGHT checklist. According to the recommendations of CPGs, there were three inconsistencies in the screening of DR, and CPGs recommendations for treatment were consistent on the whole. At the same time, recommendations for laser therapy were not accurate. Some recommendations were not specific and clear in some DR CPGs. This evidence map could collect and evaluate the characteristics of published CPGs, add to our knowledge and promote the development of trustworthy CPGs for DR.