Ophthalmic Surgery, Lasers and Imaging Retina

Clinical Science 

Examination Practices and Referral of Patients With Diabetic Retinopathy by Optometrists in Routine Clinical Care

Andrew X. Chen; Jessica Hsueh; Michael M. Han; Thais F. Conti, MD; Felipe F. Conti, MD; Wes K. Immler, OD; Amy S. Babiuch, MD; Rishi P. Singh, MD

Abstract

BACKGROUND AND OBJECTIVE:

To analyze the examination practices and referral of patients with diabetic retinopathy (DR) by optometrists in routine clinical care.

PATIENTS AND METHODS:

Diabetic patient records from 2012 to 2018 were retrospectively reviewed for documentation of dilated fundus exam (DFE), imaging, follow-up appointments, and referrals. Concordance between clinical exam and coding was also analyzed.

RESULTS:

For 97.8% of encounters, DFE was performed, the patient was referred for DFE, or DFE was scheduled for follow-up. When DFE was performed at the initial visit, this resulted in referral of 19.8% of patients to an ophthalmologist. Imaging was obtained occasionally, with fundus photos in 2.6% and optical coherence tomography in 14.5% of encounters. Concordance of DR grading between exam and coding was 78.8%. Recommended follow-up times were incorrect based on DR severity level in 13.8% of encounters.

CONCLUSION:

Although DFE was performed reliably by optometrists, utilization of imaging, DR grading and coding, and appropriate follow-up periods could be improved.

[Ophthalmic Surg Lasers Imaging Retina. 2019;50:608–612.]

Abstract

BACKGROUND AND OBJECTIVE:

To analyze the examination practices and referral of patients with diabetic retinopathy (DR) by optometrists in routine clinical care.

PATIENTS AND METHODS:

Diabetic patient records from 2012 to 2018 were retrospectively reviewed for documentation of dilated fundus exam (DFE), imaging, follow-up appointments, and referrals. Concordance between clinical exam and coding was also analyzed.

RESULTS:

For 97.8% of encounters, DFE was performed, the patient was referred for DFE, or DFE was scheduled for follow-up. When DFE was performed at the initial visit, this resulted in referral of 19.8% of patients to an ophthalmologist. Imaging was obtained occasionally, with fundus photos in 2.6% and optical coherence tomography in 14.5% of encounters. Concordance of DR grading between exam and coding was 78.8%. Recommended follow-up times were incorrect based on DR severity level in 13.8% of encounters.

CONCLUSION:

Although DFE was performed reliably by optometrists, utilization of imaging, DR grading and coding, and appropriate follow-up periods could be improved.

[Ophthalmic Surg Lasers Imaging Retina. 2019;50:608–612.]

Introduction

As of 2017, 23.1 million people in the United States had been diagnosed with diabetes, and it is estimated that 7.2 million people were undiagnosed.1 With the increasing societal burden of diabetes, optometrists can expect an increase in the number of diabetic patients and diabetic retinopathy (DR) in their practice. DR is the most common cause of vision impairment and blindness among working-age adults in the United States.2 It also has a known natural history and an asymptomatic phase, which makes it a suitable disease for screening. Over time, uncontrolled blood sugars lead to increased vascular permeability and retinal ischemia, with resultant proliferative diabetic retinopathy (PDR) and macular edema, known causes of significant visual impairment. If at-risk diabetic patients can be identified, effective treatments can be delivered, and vision loss can be prevented.

Optometrists serve as first-line providers for ocular health and, therefore, in the detection and management of DR. According to the American Optometric Association, “In 2016 alone, doctors of optometry identified diabetes-related manifestations in more than 320,000 patients who were unaware they had diabetes.” As optometrists play an integral part in preventative care, it is imperative that they are aware of diabetic status, perform a comprehensive dilated fundus exam (DFE), and recommend appropriate follow up and referral.3

According to the International Council of Ophthalmology (ICO), diabetic patients should receive comprehensive DFEs every 1 to 2 years, or more frequently if DR is present.4 Efforts have been made to determine the effectiveness of having optometrists at the forefront of screening programs for DR. One report showed that properly trained community optometrists have the potential to evaluate DR with high sensitivity and specificity,5 and another concluded that slit-lamp biomicroscopy performed by optometrists are more effective for screening than fundus photography.6 Knowing when to refer patients with more severe DR to retina specialists is also crucial in managing diabetic patients.

Trends in optometrists' management of patients with diabetes have been described to some extent. However, previous reports have been subject to inherent biases in study design, indicating the need for additional studies. The aim of this study was to retrospectively analyze the examination practices and referral of patients with DR by optometrists in routine clinical care.

Patients and Methods

This study was performed at Cole Eye Institute, Cleveland, Ohio, after receiving approval from the Cleveland Clinic Investigational Review Board. All study-related procedures were performed in accordance with good clinical practice (International Conference on Harmonization of Technical Requirements of Pharmaceuticals for Human Use [ICH] E6), applicable U.S. Food and Drug Administration regulations and the Health Insurance Portability and Accountability Act. This was a retrospective chart review of patients seen by optometrists in a large, multicenter hospital between April 2012 and May 2018. Patients were selected if they were older than 18 years of age and had a documented ICD-9 or ICD-10 code for type 1 or type 2 diabetes mellitus in the medical record. Exclusion criteria included any postoperative encounters. Demographic data about the patients' clinical status were collected. Due to the retrospective nature of the study and minimal patient risk, written informed consent was omitted.

Patient records were evaluated for the presence of a DFE and documented physical exam findings according to the International Clinical Diabetic Retinopathy Disease Severity Scale. If no DFE was performed, records were further assessed for the presence of a DFE conducted within the past year, a documented follow-up DFE, or referral to an ophthalmologist or retina specialist. If none of these actions were performed or documented, DFE was deemed “not completed” and considered an unfavorable outcome.

Patient records were also evaluated to determine average length of documented follow-up time for DR. If patients were referred, it was noted whether referral was to a retina specialist or other practicing ophthalmologist. If documentation did not show that patients were instructed to return or educated on the importance of routine examinations, the lack of follow-up was recorded as an unfavorable outcome. The utilization of imaging modalities during the patient visit, including fundus photography, fluorescein angiography, and optical coherence tomography (OCT), was also recorded. Finally, the documentation of DR was compared between assessment and plan, diagnosis list, and DFE findings, and concordance was calculated.

Dilated Fundus Examinations Conducted

Table 1:

Dilated Fundus Examinations Conducted

All statistical analyses were performed in Excel (Microsoft, Redmond, WA). Categorical variables were described using frequencies and percentages, whereas continuous variables were described using means, standard deviations, and ranges.

Results

A total of 1,300 patient records across 26 optometrists were reviewed. Of the 1,300 patients, 670 (51.5%) were female. The average age was 62.2 years ± 13.8 years (mean ± standard deviation), and 202 (15.5%) patients were on insulin. Lens status of the patients revealed that 9% were not recorded, 27% had a clear lens, 51% had a cataract, 13% were pseudophakic, and less than 1% were aphakic. The average intraocular pressure was 16.6 mm Hg ± 3.9 mm Hg in the right eye and 16.5 mm Hg ± 3.9 mm Hg in the left eye.

Providers conducted DFEs in 1,033 (79.5%) encounters. Of the remaining encounters, 172 (13.2%) patients had a DFE conducted within the last year, satisfying screening requirements. Thirty-eight (2.9%) patients were asked to return at a later date for the fundus examination. Twenty-nine (2.2%) patients were referred to either a retina specialist or a general ophthalmologist, often on the basis of exam other than DFE. Twenty-eight (2.2%) patients did not receive fundus examination or follow-up and were hence considered unfavorable outcomes.

Of the patients who had a DFE, 105 (8.1%) were referred to a retina specialist, 152 (11.7%) were referred to other ophthalmologists, 105 (8.1%) were documented to return within 3 months, and 45 (3.5%) were documented to return within 6 months. A total of 183 (14.1%) did not have instructions for further visits documented in the encounter.

Follow-Up Time

Table 2:

Follow-Up Time

In high-resource settings such as the institution being studied, the ICO recommends follow-up in 1 to 2 years for no DR, 6 to 12 months for mild nonproliferative DR (NPDR), 3–6 months for moderate NPDR, less than 3 months for severe NPDR, and less than 1 month for PDR.4 For our cohort, the distribution of follow-up times and referrals was determined for each patient group categorized by DR severity. The following results reflect practices that are not always adherent to these guidelines. Of the 266 patients who had no DFE, 95 (36.7%) received no follow-up instruction, Of the 899 patients who had no DR pathology on DFE, 81 (9.0%) had no follow-up instructions documented, 58 (6.5%) were recommended to follow-up in 3 months, and 29 (3.2%) were recommended to follow-up in 6 months. Of the 106 patients who had mild-to-moderate NPDR, seven (6.6%) had no follow-up documented. It was not possible to determine if documented follow-up durations for patients with mild-to-moderate DR were exactly according to guidelines because there was consistent lack of documentation to determine between mild and moderate DR, and the ICO recommends differential follow-up for these conditions. Of the six severe NPDR patients, one (16.7%) was recommended to follow-up in 6 months whereas the remaining five (83.33%) were referred accordingly to a general ophthalmologist or a retina specialist. Of the 23 PDR patients, two (8.7%) were asked to follow-up in 6 months and two (8.7%) were asked to follow-up in 12 months. The remaining 19 were referred accordingly. In summary, documented follow-up times were too short for at least 87 (6.7%) patients and too long for at least 93 (7.2%) patients.

Patient referral to either general ophthalmology or retina specialists was grouped by DR severity. Of the 152 (11.7%) patients referred to general ophthalmology, 18 (11.8%) had mild or moderate NPDR, two (1.3%) had severe NPDR, and two (1.3%) had PDR (Table 3). Of the 105 (8.1%) referrals to a retina specialist, 29 (27.6%) had mild or moderate DR, three (2.8%) had severe NPDR, and 17 (16.2%) had PDR (Table 3).

Follow-Up Times by DR Severity as Determined by DFE

Table 3:

Follow-Up Times by DR Severity as Determined by DFE

Fundus photography was obtained in 34 (2.6%) encounters and OCT in 189 (14.5%) encounters. No fluorescein angiogram orders were recorded in the 1,300 encounters reviewed.

The overall concordance between the assessment and plan (A&P), ICD codes, and DFE findings was 78.8%. Concordance between A&P and ICD codes was 95%, between ICD codes and DFE was 80%, and between A&P and DFE was 82%.

Discussion

In a society where the number of diabetics continues to grow, it is inevitable that optometrists will see more diabetic patients in their practices. This study was conducted to assess the examination of DR and the referral patterns of optometrists in routine clinical practice during a 5-year period. Optometrists play a key role as first-line providers of eye care, particularly for detecting signs of retinopathy in patients with diabetes. Previous studies have been performed in an effort to determine trends in the management of DR by optometrists. One such study reviewed a volunteer sample of patient charts from optometrists and found that 85.8% of diabetic patients were dilated during their last comprehensive exam. Patients who were dilated returned to care an average of 0.7 years sooner than those who were not.7 Another study utilized surveys sent to licensed optometrists in New York state and revealed that routine retinal exams were performed by 68% of providers who saw patients with diabetes, and 62% of these providers dilated the pupils. Although 91% recommended annual exams to diabetic patients, only 68% recommended dilated exams specifically.8 These studies demonstrate that optometrists perform DFEs at a less-than-ideal rate. However, conclusions drawn from these findings should be accepted with caution as they may be limited by significant recall and selection bias.

Our findings indicate that for 1,272 (97.8%) of all first-time visits with diabetic patients, a DFE was either performed or had been performed within the past year by another provider, the patient was asked to return for a DFE, or the patient was referred to an ophthalmologist (Table 1). However, 28 (2.2%) first-time visits did not result in a DFE, follow-up instruction, or referral, indicating that this small group of patients did not receive standard of care. Possible causes for this include unawareness by the provider of the patient's diabetic status, inconsistent charting, and lack of electronic medical record prompts to indicate the patient was diabetic.

Guidelines state that diabetic patients should receive routine comprehensive DFEs every 1 to 2 years as standard of care to monitor DR and prevent vision loss. Of patients in this study, 1,117 (85.9%) had the proper follow-up documented on their exam or were referred after their first encounter. However, a considerable 183 patients (14.1%) had no documented follow-up in their medical record (Table 1). Of these patients, seven (7%) had mild or moderate NPDR according to their DFE (Table 3). According to guidelines of the ICO,4 patients with moderate NPDR, severe NPDR, or PDR should be referred to ophthalmology for further evaluation. However, one patient (16.7%) with severe DR and four (22.2%) with PDR either had no follow-up documented or were followed by an optometrist rather than referred. This totals five missed referrals to ophthalmology for the co-management of DR.

Although we expected DR patients to be referred mostly to retina specialists, this was not always the case. We hypothesize that certain NPDR and PDR cases (Table 3) were referred to general ophthalmology instead of a retinal specialist likely because of more acute or comorbid ophthalmological disease that was not retina-related, lack of accessibility to a retina specialist, or lack of education in referral practices. Additionally, 24 retina referrals (22.8%) had no DR, which was likely due to referral for a non-diabetic-related retinal disease.

Fundus photography has proven useful both as an adjunct to DFE and as a replacement for dilated examination in telemedicine programs across the country.9 In addition, fluorescein angiography (FA) is the current gold standard in evaluating retinal vasculature.10 OCT is an imaging technique useful in measuring and managing macular edema in diabetics.11 In our study, 34 (2.6%) fundus photos and 189 (14.5%) OCTs were performed (Table 4). No fluorescein images were obtained for any of the 1,300 patients (Table 4). Although these results may be a limitation of available imaging technology within each optometrist's site, use of fundus photography is the standard of care for diabetic patients and they can help with the detection of DR and classifying its severity, so their use should be encouraged.

Imaging Obtained

Table 4:

Imaging Obtained

Finally, the concordance between A&P, ICD codes, and DFE was analyzed. Overall concordance between all three measures was 79%. Concordance was highest between A&P and ICD codes (95%) likely because the ICD code assigned corresponded to the provider's clinical assessment, or the use of automated functions within the medical record that transfer the ICD code to the A&P. Concordance between ICD codes and DFE was 80%. Similarly, concordance between the A&P and DFE was 82%. This substantial disparity between findings recorded on the physical exam and findings recorded on A&P and ICD codes may indicate either lapses in proper medical documentation or inaccurate classification of DR severity based on examination findings, highlighting areas where further education could prove useful.

Overall, our results indicate that most diabetic patients are appropriately receiving routine eye exams by optometrists and that they are receiving proper follow-up appointments and referrals to receive care. We identified an area of concern in identifying which patients should receive more specialized care to address possible DR. Educational efforts aimed toward optometrists to explain situations where referral may be beneficial could result in more referrals of NPDR and PDR to retina specialists to better co-manage diabetic patients.

In summary, proper detection and treatment of DR are key public health concerns because they can greatly reduce the possibility of vision loss in diabetic patients. Optometrists are positioned in primary care settings that are suited for performing preventative eye care, and they are well-trained in performing dilated eye exams in diabetic patients. Providing optometrists with further educational and imaging tools to better identify patients who require referral to retina specialists may decrease diabetic eye disease burden in the United States.

References

  1. Centers for Disease Control and Prevention. National Diabetes Statistics Report, 2014: Estimates of Diabetes and Its Burden in the United States. https://www.cdc.gov/diabetes/pdfs/data/2014-report-estimates-of-diabetes-and-its-burden-in-the-united-states.pdf. Published 2017.
  2. Kempen JH, O'Colmain BJ, Leske MC, et al. The prevalence of diabetic retinopathy among adults in the United States. Arch Ophthalmol. 2004;122(4):552–563. doi:10.1001/archopht.122.4.552 [CrossRef]15078674
  3. Middleton D. American optometric association survey reveals misconceptions about diagnosing diabetes and its related eye diseases. American Optometric Association website. https://www.aoa.org/newsroom/november-2017-diabetes-awareness-month. Published October 31, 2017.
  4. Wong TY, Sun J, Kawasaki R, Ruamviboonsuk P, et al. Guidelines on Diabetic Eye Care: The International Council of Ophthalmology Recommendations for Screening, Follow-up, Referral, and Treatment Based on Resource Settings. Ophthalmology. 2018;125(10):1608–1622. doi:10.1016/j.ophtha.2018.04.007 [CrossRef]29776671
  5. Prasad S, Kamath GG, Jones K, Clearkin LG, Phillips RP. Effectiveness of optometrist screening for diabetic retinopathy using slit-lamp biomicroscopy. Eye (Lond). 2001;15(Pt 5):595–601. doi:10.1038/eye.2001.192 [CrossRef]
  6. Prasad S, Swindlehurst H, Cleaqrkin LG. National screening programme for diabetic retinopathy. Screening by optometrists is better than screening by fundus photography. BMJ. 2001;323(7319):998–999. doi:10.1136/bmj.323.7319.998 [CrossRef]11700632
  7. Puent BD, Nichols KK, Scarborough R. The frequency of dilated diabetic eye. Optom Vis Sci. 2010;82(11):959–963. doi:10.1097/01.opx.0000187845.74076.9f [CrossRef]
  8. Olsen CL, Gerber TM, Kassoff A. Care of diabetic patients by optometrists in New York State. Diabetes Care. 1991;14(1):34–41. doi:10.2337/diacare.14.1.34 [CrossRef]1991433
  9. Goh JKH, Cheung CY, Sim SS, Tan PC, Tan GSW, Wong TY. Retinal imaging techniques for diabetic retinopathy screening. J Diabetes Sci Technol. 2016;10(2):282–294. doi:10.1177/1932296816629491 [CrossRef]26830491
  10. Or C, Sabrosa AS, Sorour O, Arya M, Waheed N. Use of OCTA, FA, and ultra-widefield imaging in quantifying retinal ischemia: A review. Asia Pac J Ophthalmol (Phila). 2018;7(1):46–51.
  11. Virgili G, Menchini F, Murro V, Peluso E, Rosa F, Casazza G. Optical coherence tomography (OCT) for detection of macular oedema in patients with diabetic retinopathy. Cochrane Database Syst Rev. 2011;(7):CD008081.21735421

Follow-Up Times by DR Severity as Determined by DFE

Follow-Up No DFE Normal Mild/Moderate NPDR Severe NPDR PDR
No follow-up 95 (35.7%) 81 (9%) 7 (6.6%) 0 (0%) 0 (0%)
3 months 36 (13.5%) 58 (6.5%) 11 (10.4%) 0 (0%) 0 (0%)
6 months 2 (0.8%) 29 (3.2%) 11 (10.4%) 1 (16.7%) 2 (8.7%)
12 months 36 (13.5%) 642 (71.4%) 30 (28.3%) 0 (0%) 2 (8.7%)
Referral to general 65 (24.4%) 65 (7.2%) 18 (17%) 2 (33.3%) 2 (8.7%)
Referral to retina 32 (12%) 24 (2.7%) 29 (27.4%) 3 (50%) 17 (73.9%)
Total 266 (100%) 899 (100%) 106 (100%) 6 (100%) 23 (100%)

Dilated Fundus Examinations Conducted

Done in Encounter 1,033 (79.5%)
Of the Remaining 267 (20.5%)
  Done within last year 172 (13.2%)
  Referred 29 (2.2%)
  Told to return 38 (2.9%)
  Not completed 28 (2.2%)

Imaging Obtained

Optical coherence tomography 189 (14.5%)
Fundus photography 34 (2.6%)
Fluorescein angiography 0 (0.0%)

Follow-Up Time

No follow-up 183 (14.1%)
Within 3 months 105 (8.1%)
Within 6 months 45 (3.5%)
Within 12 months 710 (54.6%)
Referral General 152 (11.7%) Retina 105 (8.1%)
Authors

From Case Western Reserve University School of Medicine, Cleveland, Ohio (AXC, JH, MMH, RPS); Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio (TFC, FFC, ASB, RPS); and the Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio (TFC, FFC, WKI, ASB, RPS).

Supported by a continuing medical education grant from Genentech.

Dr. Babiuch has received personal fees from Allergan, MCME Global, and Vindico outside the submitted work. Dr. Singh has received grants and personal fees from Genentech during the conduct of this study, as well as grants and personal fees from Regeneron and Novartis/Alcon and personal fees from Optos, Bausch + Lomb, and Zeiss outside the submitted work. The remaining authors report no relevant financial disclosures.

Dr. Singh did not participate in the editorial review of this manuscript.

Address correspondence to Rishi P. Singh, MD, 9500 Euclid Avenue, Desk i32, Cleveland, OH 44195; email: SINGHR@ccf.org.

Received: August 09, 2018
Accepted: March 11, 2019

10.3928/23258160-20191009-02

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