It seems rather odd for a Jerusalem team to devise a test based on artificial intelligence (AI) that studied 1,124 Latin American and African American in the Bronx to accurately predict who is at risk for developing proliferative diabetic retinopathy (PDR), a disease that can result in blindness. After all, these two ethnic groups have different genetic makeups than Israeli Jews and Arabs, and the findings could be irrelevant to them. Why bother except to help American patients?
In fact, there is a method in this seeming madness. Their findings that a simple blood or urine test based on relevant factors to predict risk proved a technique that can be adapted to other ethnic groups – a boon provided by personalized medicine.
Dr. Ayelet Goldstein, a lecturer in the computer science department of Hadassah Academic College in the center of Jerusalem, teamed up with Dr. Jonathan Levine of the college’s optometry department, who, before his aliyah in 2015, worked in the BronxCare Health System in New York City. He has retained contacts with former colleagues and, therefore, had access to their data.
They have just published their study in the international journal Ophthalmic Physiology and Physiological Optics under the title “Prediction of Proliferative Diabetic Retinopathy using Machine Learning in Latino and Non-Hispanic Blacks Cohorts with Routine Blood and Urine Testing.”
In an interview with The Jerusalem Post, Levine pointed out that while the rate of type 2 diabetes is high in Israel, it is much higher in the Bronx, which is one of the poorest places in the US and whose residents are at high risk of diabetes and PDR. Because of the high level of community medicine from Israel’s public health funds, vision complications from years or decades of type 2 diabetes are uncommon. Still, he said, there could be some 5,000 Israelis at risk for PDR whose disease could be headed off by the new technology. This would mean that the eyesight of hundreds of Israelis could be saved.
“The goal of our research was not to find an alternative to an eye exam but to help doctors identify those who urgently need an exam. The study results show the revolutionary potential of a AI in patient health,” added Levine, whose father is an Israeli kidney specialist.
“The blood and urine tests we customized included standard ones, levels of HbA1C, kidney-function, creatinine, albumin, low-density lipoprotein cholesterol, and more. AI found what is most predictive. Many patients have been diagnosed with diabetes, but they usually don’t visit an eye doctor every year, and they come too late. If we can identify those at risk, we can diagnose them faster. This invests medical resources in a smarter way.”
Now that the team members in Jerusalem have a relevant, customized formula of tests, they are very eager to conduct a study on Israeli diabetics. “The study demonstrated a proof of concept for the technique. Now that it has been published in a respected journal, we can apply for a grant and conduct research relevant to the Israeli population and our ethnicity and gender – Jews and Arabs, Ashkenazi and Sephardi, men and women.”
Levine works for Clalit Healthcare Services and Maccabi Healthcare Services – the country’s two largest health funds – in Gush Etzion. “Patients are well cared for. Relevant patients in the area with eye problems are referred to me by family physicians. I see a lot of healthy eyes – but if I worked in a tertiary hospital’s ophthalmology department, I would surely see more pathology.”
Type 1 Diabetes
UNCONTROLLED TYPE 1 diabetes, which is an autoimmune disease and often begins in childhood, can also lead to PDR, which is the advanced stage in which abnormal new blood vessels grow on the surface of the retina of the eye. These vessels may break and bleed into the vitreous – the clear watery gel that fills the eye – and cause severe vision loss. This stage of diabetic retinopathy always requires urgent treatment.
The condition has two stages – non-proliferative retinopathy is the early stage of the disease in which blood vessels swell and leak. In some cases, this can cause macular edema (swelling of the retina), which may result in mild vision loss but can be treated. In the early stages, you may have no symptoms at all, and your vision may not change until the disease gets worse. There may also be early changes to the nerve cells in the retina that may affect vision, partly due to loss of an adequate blood supply, Levine explained.
While diabetic retinopathy often cannot be completely prevented, one can reduce the risk of having it develop or progress. Controlling your blood sugar slows the start of retinopathy and prevents it from getting worse. It also lessens the need for laser surgery or other procedures that treat severe retinopathy.
Anyone with chronic high blood sugar levels due to diabetes is at risk for PDR. The longer one has diabetes, the more likely you are to get it. The risk rises if you have diabetes and also smoke, have high blood pressure, or are pregnant.
When the disease progresses, you may have blurry or double vision, blank spots or rings in your field vision, dark or floating spots, pain or pressure in one or both eyes or flashing lights.
A condition called macular edema may result from PDR. This occurs when the macula – the central part of the retina – swells from the leaking fluid and causes blurred vision. When new vessels grow on the retina’s surface, they can bleed into the eye and decrease vision as well.
ORDINARILY, diabetics don’t go to an eye doctor regularly, so they don’t know of their PDR risk, Levine continued. “Your eye doctor may do the following tests, as well as a complete health history and eye exam, to diagnose the condition.
One’s kidneys filter the blood by removing waste and extra water to make urine. The glomerular filtration rate (GFR) shows how well the kidneys are filtering. An estimated 37 million American adults have chronic kidney disease (CKD), but nearly 90% are unaware of their condition. When found early, people can take important steps to protect their kidneys.
Getting an accurate GFR level is challenging because measured GFR (mGFR) is a complicated and lengthy process. This makes it impractical for both clinicians and patients. It is for this reason that healthcare professionals use a formula to estimate GFR. Often, CKD doesn’t involve any symptoms until the later stages of the disease. This is the reason why reliable estimates of GFR are so important for identifying CKD as early as possible.
The standard way to estimate GFR is with a simple blood test that measures your creatinine levels. Creatinine is a waste product that comes from the digestion of dietary protein and the normal breakdown of muscle tissue. Aside from CKD, creatinine levels can be affected by other factors, including diet, the weight of your muscles, malnutrition, and other chronic illnesses.
Goldstein explained that “we saw that the cutoff values of the various indices as well as the degree of their influence vary between the sexes and among the different ethnic groups. For example, in the eGFR index, we found considerable differences in the cutoff value of the different ethnic groups – African-American women with values of eGFR lower than 51.1 had a high chance of getting sick compared to eGFR lower than 70.7 for Latin American women.
GOLDSTEIN, who holds a bachelor of science degree and MBA from the Hebrew University of Jerusalem and a Ph.D. from the Ben-Gurion University of the Negev in Beersheba, is especially interested in temporal reasoning, natural language generation, summarization, and knowledge-based systems. She teaches undergraduate and graduate programs in the computer science department.
She noted that their model determined with 85% accuracy who had PDR or was at risk. With the new technique, the Bronx patients can undergo customized urine and blood tests and be given them priority.
Treatment for PDR will depend on one’s symptoms, general health, and age as well as how severe the condition is. Even patients with advanced retinopathy have a good chance of keeping their vision if they are treated before the retina becomes severely damaged.
Treatment may include one or a combination of the following: laser surgery to shrink the abnormal blood vessels or seal the leaking ones.
Vitrectomy involves removing the jelly-like vitreous that fills the eye’s center and replacing it with a balanced saline (salty water) solution. Certain medications can be injected into the eye to slow the growth of the abnormal vessels of the retina and to treat macular edema.
Diabetics should go for a yearly eye exam. Women with diabetes should have an eye exam before pregnancy or in the first trimester. They should continue to be monitored every trimester and for one year after birth, depending on the severity of the retinopathy.
Among patients aged 25 to 74, PDR is a leading cause of vision loss worldwide – and by 2030, an estimated 191.0 million people globally will have diabetic retinopathy. Over 56 million are expected to contract vision-threatening PDR.