Diabetes mellitus (DM) is an increasingly common metabolic disorder in the US and developed nations, and is affecting younger patients, effectively increasing the role of the ophthalmologist in the care of such patients as longer duration of diabetes increases the risk of diabetic eye disease [1]. According to the WHO there are more than 346 million persons worldwide who are living with DM-over 90% of which have type 2 diabetes mellitus (DM2) [2]. Diabetic retinopathy (DR) and diabetic macular edema (DME) are responsible for considerable morbidity in patients with DM, and is currently a serious public health problem as DM increases [3-5]. Diabetes education is a key component in management of DM and its many complications (a PubMed search for ‘“patient education” and diabetes’ yielded almost 9000 unique titles) yet many patients still do not understand their disease, its management, complications, or treatments, despite current clinical patient education paradigms. The American Academy of Ophthalmology and the American Diabetes Association, among many medical associations, highly advocates patient education through educational handouts, webpages, teaching, etc. and many of these resources are invaluable to patients.

Much has been written on education of patients with DM in general, but what is the outcome of education on patients with established disease? The medical literature has a plethora of information on the effects of DM and the treatment of diabetic eye disease (DED), as well as the paucity of information on the outcomes of all that education [5-10]. This leads to a gap in knowing what areas of patient education need more attention, and particularly which patients are at risk of complications from DM due to lack of understanding of their disease.

Despite all the education, many patients do not seem to understand their disease or treatment regime. Patients being treated for retinopathy are an excellent cohort to examine as their diabetes has had to have been established long enough and with poor enough control to exhibit the end organ damage. They are patients living with chronic disease, being treated in an ongoing care setting. The purpose of this study was to review patients at a large retinal practice in Los Angeles, using three separate sites and patients from 8 retinal surgeons, on their understanding of DM and their treatment regime. Issues examined included basic demographic information, understanding of DM, understanding of risk factors, awareness of one’s own disease and the treatments currently undertaken at the retinal clinic.

This prospective study had obtained an IRB approval through Quorum IRB.

Standard clinical practice in this setting has all patients receiving a handout from the physician from the AAO on diabetes and diabetic eye disease (DED), and it is routine at each visit to inquire about fasting blood sugars, blood pressure, and hemoglobin A1C, which is transcribed into the patient’s chart for documentation. Patients are counseled by the physician on glucose and blood pressure control, and correspondence is sent back to the primary care physician regarding the diagnosis and treatments undertaken after the visit.

Consecutive patients who had at least 5 previous visits to the retinal clinic (to establish a history of care in the practice), and have a diagnosis of DR were asked to participate in a 15 question survey, administered by ophthalmic technical staff in the office. Patients were instructed that the survey was entirely optional and they were free to withdraw at any time should they agree to participate. The ophthalmic staffs were instructed to read the survey questions in either English or Spanish to the patient, and not to prompt the patient. Answers requiring verification were verified against the information contained in the patient’s chart by the technician at the time of the questionnaire completion. At times where patients were asked to provide a list of symptoms/signs (eg what complications can diabetes cause to your eyes?) if the technician felt the answer was close (eg. Diabetic Macular Edema, or swelling of the retina) the answer was scored as correct; if unsure the technician was to record the answer verbatim, and the answers we reviewed by the author for appropriate scoring. The technician and physician were looking for an approximate understanding from the patient, not exact medical terminology.

Patients were informed that their treating physicians were not aware of who was taking the survey and were free to decline or withdraw at any point. A selected technical staff at each office participating (three in total) were assigned to collect the data during normal clinic screening time, and only that technician conducted and filled out the survey at each site to ensure consistency. An ethics approval from Quorum Review IRB was obtained prior to starting the study.

100 surveys were conducted at three different sites, with approximately equal distribution of surveyed patients taken from each site. When asked if “you feel you understand diabetes”, 97% of patients answered “yes”.

Demographics

61% of patients were 61 years of age or older (Table 1), and half of the patients had done some post-secondary educational training. Twenty-seven percent were of Caucasian descent, and 38% were of Hispanic origin.

Table 1: Patient Demographic.

Forty-five percent of patients have had DM for over 20 years. With 8% having had it for more than 40 years. (Table 2).

Table 2: Duration of DM.

Knowledge of DM and Treatment

Regarding knowledge of their DM, 80% identified as having type 2 DM, and 10% as having type 1 DM, and 10% were unsure as to which type they had. 83% were correct in their identification of which type they had, and 14% (including the 10% of all patients who did not know) were incorrect. For 3% of patients it was not determinable by the chart which type of DM they had.When asked how their DM is controlled, 64% identified oral medication, 54% identified insulin, 40% identified diet control, and 12% identified exercise. However when asked for ways to control DM, only 67% indicated diet and 26% identified exercise as helpful (Tables 3 and 4).

Table 3: How patients control their DM.

Table 4: What patients feel they can do to control their DM.

95% of patients correctly identified that blood pressure control is important to monitor. However 39% were unable to identify what their blood pressure readings usually are, and 31% identified their systolic blood pressure as being over 130mmHg regularly (7% described it as usually great than 150 mmHg).

Day of survey fasting blood glucose (FBG) reading was known in 89% of patients. Only 35% of patients had a FBG of less than 130 mg/dl. (Table 5) When asked what the range of their blood sugars usually are, 6% did not know what their FBG usually was, 17% described their FBG as greater than, or a range that included values greater than, 160 mg/dl.

Table 5: Current Blood Sugar Reading.

Half, 50% of patients knew what a hemoglobin A1C (HbA1C) is, and of those, 56% (28/50) identified that it was an indication of long-term control of blood glucose. When asked about the current numerical value of their HbA1C, of all patients, 59% did not know, 7% had a value of less than 6, 10% had a value of 6.0-6.9, and 2% had a value of greater than 11% (Table 6).

Table 6: Known Hemoglobin A1C values.

Regarding DR status, 91% of patients did not know if they had proliferative or non-proliferative DR (of those who could identify their DR status, 3% identified non-proliferative, and 6% identified proliferative DR). According to the patient charts, 36% of patients had non-proliferative, and 61% had proliferative DR. There was no diabetic retinopathy documented in the remaining 3% of charts.

Patients were asked to identify which treatments they had received for their diabetic eye disease. They were asked if they had received laser, injections, vitrectomy surgery, or just surveillance. 56% named all correct treatments they received, with an additional 31% getting most treatments correct but forgetting one (for example: 14% had forgotten that they had laser treatment). 13% could not identify how their diabetic eye disease was being treated (Table 7).

Table 7: Patient knowledge of treatment.

Knowledge of Diabetic Complications

Patients were asked about their understanding of complications from diabetes: as all were currently being treated for DED. Bleeding of the eye was identified by 23%, although swelling, or macular edema, was only identified by 7%. A large majority, 73%, did identify blindness or visual loss, as a complication (Table 8).

Table 8: Patient awareness of visual complications from DM.

Patients were also asked to describe systemic complications from DM. Peripheral neuropathy was identified by 45%, and 34% identified renal damage. Amputations were identified by 5%, and stroke was identified by 6%. However, 9% were unsure of other complications from diabetes that they may be experiencing (Table 9).

Table 9: Additional complications identified by patients.

Understanding Based on Age of Patient

When the data was broken down based on patient age, there was not an equal distribution across ages. There was one patient younger than 30. There were no patients 31-40. Older patients were approximately equally distributed (age 41-50: 13 patients; age 51-60: 25 patients; age 61-70: 30 patients; and age >70: 31 patients). As patient age increased, the ability to correctly identifying current treatments, and knowledge of what HbA1C was, decreased (Figure 1).

Figure 1: Percentage of patients correctly identifying Treatment and HbA1C compared to age.

Understanding based on educational level of the patient

When the data was broken down based on maximal attainment in education: 15 patients had 8th grade or less; 33 had obtained high school; 33 had some college education; and 19 had professional/graduate school education. Across all levels, identifying which treatments they had undergone was similar. Ability to correctly identify what HbA1C is increased with increasing education. Only 2/15 patients with 8th grade or less of education knew what HbA1C was but both had a current HbA1C of less than 8% (Figure 2).

Figure 2: Percentage of patients correctly identifying Treatments, HbA1C, and having an A1C of less than 8.

Complications of DM are well known in the medical literature, and much literature exists about patient education. While there are many factors involved in patient understanding of disease, it is very important for patient understanding for improved outcomes [3-6,11].

Our study looks at patients already diagnosed and being treated for advanced complications from DM. Five percent of participants had previously had amputations. All patients were currently being treated (and having been seen on at least 5 prior occasions) at a retinal practice for DED. Forty-five percent of patients had had DM for over 20 years. In accordance with current practice at the offices, all patients had been educated by physicians in the practice regarding their eye disease, treatments, and regarding risk factors (including hypertension, glucose controls, and HbA1C).

Despite the current educational practices employed by the practice, as well as at their primary or diabetologist offices, 74% of patients with established DM did not identify exercise as a means of controlling DM and 33% did not identify dietary habit. Four percent did not know what to do to control their DM, despite being currently treated for DM. Diet and exercise are cornerstones in DM care, and can decrease insulin and oral medication use, and yet that message does not seem to be well understood by many complicated DM patients.

Of these patients with advanced diabetic complications, 11% did not currently know their FBG, and 4% had a FBG of greater than 200 that day. Poor control, and lack of understanding of the important measures in diabetic control may contribute to why these patients were being treated for DED and had a high self-reported rate of additional complications related to DM. HbA1C was largely unknown (59%) despite patients being asked at all 5 prior appointments what their HbA1C was (as well as being instructed to communicate what the HbA1C with the office at all appointments). Of the remaining 41%, 12% had a HbA1C of greater than 8%. Again this high HbA1C correlates with the high FBG, poor diabetic control, and high complication rate in these patients. When this was broken down based on age, the more elderly the patient, the less likely they were to know what HbA1C was (for patients over 70 years, only 42% were able to correctly identify what HbA1C was). As education levels increased, knowledge of HbA1C also increased, although in this age group, knowledge of HbA1C did not correlate with lower levels of glycosylated hemoglobin (Chart 2).

Over 85% of patients were able to correctly identify their treatments to some degree, with 56% knowing the exact treatments they had received. When this was broken down based on age, the more elderly the patient, the less likely they were to know which treatments they had had (for patients over 70 years, only 65% were able to correctly identify their treatments). It seems that across all levels of education, patients were able to identify most treatments they had had (85-95%). Patient understanding of disease treatments is especially important in the setting of multiple medical issues, for communicating between patient’s different doctors, and in cases of changes to providers mid-course of therapy. Most patients seemed to have a reasonable understanding of their course of therapy, despite not having a good understanding of how to achieve, and what constitutes, good glycemic control.

This study was not powered to prove differences between any sub-groups of patients. This study was a survey method, done on consecutive patients at three different offices from a large retinal practice in Los Angeles, with the surveys being divided roughly equally between all offices. Voluntary surveys have an inherent risk of selecting persons who are willing to volunteer their ideas, and the study methods does bias towards patients who are more comfortable and confident in their answers (as the survey was done in front of a technician, and therefore not completely anonymously). This study, however, does give us a glimpse in the niche of patient education and understanding for patients with advanced DM and DED.

This survey does demonstrate some trends towards patient misunderstanding on how DM is treated, what the risk factors are, how monitoring should be done. Emphasis still needs to be made on diet modification and exercise in controlling DM and its end-organ changes. Certain patients may be at risk for not understanding DM care and treatment, based on current commonly practiced educational methods (those with lower educational achievement, or more elderly patients). Additional resources may need to be developed for these sub-sets of patients to provide better understanding of treatments and therapies.

No author has any potential conflict of interests related to the subject of this manuscript.