Keeping Your Eyes and Lower Limbs Healthy
By Andrew Briskin
High blood glucose levels from diabetes can cause damage to your eyes, arms, legs, and feet. Experts recently shared several ways you can prevent or treat these complications.
Diabetes can cause a range of complications, from eye diseases and impaired kidney function to nerve damage and a reduced ability for the heart to pump blood to the brain and extremities (arms, legs, and feet.)
As many with diabetes might know, the condition is among the leading causes of blindness and limb amputation worldwide. The good news is that these outcomes – and the complications that lead to them, such as diabetic eye diseases and peripheral artery disease (PAD) — may be prevented with careful management of blood sugar levels and overall vigilance of the disease.
In diaTribe’s latest Musings panel “Addressing Complications: Keeping Your Eyes and Extremities Healthy,” four leaders in diabetes care discussed how people with diabetes can look out for the symptoms of eye disease and PAD, and how those conditions can be treated. You can watch the full panel below.
Dr. Manuel Amador, retina specialist and medical director in Ophthalmology Medical Affairs at Genentech
Dr. Richard Browne, clinical cardiologist and senior medical executive, Health Systems Strategy at Janssen Pharmaceutical Cardiovascular and Metabolism
Dr. Diana Isaacs, endocrinology clinical pharmacist and certified diabetes care and education specialist, Cleveland Clinic Endocrinology and Metabolism Institute
Dr. Paolo Silva, co-chief telemedicine at Beetham Eye Institute of Joslin Diabetes Center and associate professor of ophthalmology at Harvard Medical School
What is peripheral artery disease (PAD)?
The cardiologist on the panel, Browne opened the discussion by explaining the process that leads to PAD.
He said that the two types of blood vessels in the body are veins, which take blood from the body back to the heart, and arteries, which take blood from the heart to the body. The arteries in the arms and legs that deliver blood are known as the peripheral arteries.
“Peripheral artery disease starts with a plaque forming and attaching itself to the inner lining of the artery,” said Browne. “Platelets, the sticky substances in your blood, can then attach to the plaque, which can cause a clot to form. This leads to blockages in the artery and reduced blood flow in the blood vessel. If this process occurs in the arteries going to your arms or legs, you can develop the signs and symptoms of peripheral artery disease, with the worst complication being an amputation.”
Browne said that high glucose levels can accelerate this process of blockages in the arteries, which is why people with diabetes have more than four times the risk of developing PAD compared to those without.
Symptoms of peripheral artery disease
Symptoms of peripheral artery disease include:
Cramping in the back of legs, or pain in the back of calves when walking
Numbness or weakness in feet
Frequently cold feet; this may be a sign that feet and toes aren’t getting enough blood
Burning sensation in legs or feet
Foot sores that aren’t healing
“The best treatment for PAD is early detection. That significantly reduces your risk for a heart attack, stroke, or an amputation,” Browne said, highlighting that all people with diabetes should look out for the symptoms of PAD.
Browne said that roughly 40% of people with diabetes and PAD do not feel any symptoms, so everyone with diabetes should get evaluated for PAD annually.
“There is a very simple, non-invasive test called the ABI [ankle brachial index] that basically takes the blood pressure in your arm and the blood pressure in your leg, and compares the values,” he said. “When the ABI falls below 0.9, that is an indication of potential peripheral artery disease.”
Prevention and Treatment of PAD
Experts agreed that prevention and early detection are the best treatments for PAD. Browne mentioned a few actions that people with diabetes can take, which include:
Regular exercise, which could be a routine walking program
Stopping smoking – Browne said that smoking quadruples the risk for PAD
Getting screened for kidney disease (kidney disease can elevate the risk for PAD)
Foot health: Take off your shoes and socks at doctor’s visit and make sure your feet are examined
There are also medications that can help prevent PAD, as well as procedures to treat the symptoms of the condition if it has progressed.
Statins, which lower cholesterol, and ACE inhibitors, which lower blood pressure, are two of the most common.
“Guidelines suggest that anyone with diabetes over the age of 40 benefits from being on a statin, possibly at lower ages depending on risk factors,” said Isaacs, a diabetes care and education specialist. “Many of these medications have been shown to have benefits, even after getting your numbers to goal.” She said that both statins and ACE inhibitors are widely available at low cost.
Two types of diabetes medications, GLP-1 receptor agonists and SGLT-2 inhibitors, lower glucose levels and also might benefit people with PAD.
“These drugs lower glucose levels and increase time in range, but irrespective of that, they have been shown to improve cardiovascular outcomes [like PAD] in type 2 diabetes,” said Isaacs.
For those who have developed a blockage in the artery, several procedures called revascularization may restore blood flow, as a doctor goes through the skin and uses a balloon to push away the plaque, or a surgeon bypasses the blockage with an operation.
What are the different types of diabetic eye diseases?
On the panel, two ophthalmologists (eye specialists) explained the different types of eye diseases and why people with diabetes are at a greater risk.
Amador started with the most common eye complication of diabetes, retinopathy. “Diabetic retinopathy involves the smaller blood vessels that are in the retina, the layer of the eye that allows us to see. Retinopathy specifically affects a crucial area of the retina, called the macula,” he said.
“Once the macula is affected, we start seeing problems with vision and the symptoms of retinopathy. The last step of this disease can be complete vision loss because this problem can continue progressing without treatment,” he added.
Silva added, “Patients with diabetes are at higher risk for developing age-related cataracts and glaucoma. With the retina, we mainly see diabetic retinopathy and diabetic macular edema (DME). This is when you have swelling of the macula, which is responsible for central, and clear, crisp vision. When we have DME, vision is substantially affected.”
Symptoms of diabetic eye diseases
The earliest signs of retinopathy or DME include:
Blurred or fluctuating vision
Empty areas of your vision
Spots floating in your vision
Both Silva and Amador agreed that people with diabetes should get screened regularly by an eye specialist, and as soon as possible if they are experiencing any of these symptoms.
“Sometimes retinopathy can start in one eye and not the other, and sometimes our brain doesn’t even realize this and compensates with the other eye,” said Amador. “Screening should happen once a year, maybe more often depending on the severity. Have a regular checkup with your retina specialist. They can even take a picture [of the retina] and better understand what’s going on and compare [pictures] over time.”
Silva said that these checkups are easy and convenient and can be done without an eye specialist.
“There are screening programs located in primary care offices or endocrinology clinics that rely on pictures of the retina [taken by special cameras],” he said. “These photos are taken without eye drops and are easy, fast, and convenient in under 15 minutes. These cameras can diagnose the presence and severity of retinal disease in the eye. Most federal programs like the VA and Indian Health Service, for instance, have access to these cameras.”
Treatments for retinopathy and macular edema
The treatments for eye complications include a type of injectable eye medication and laser treatment.
“Common treatments for diabetic eye disease include injections to the eye, which can cause a lot of anxiety among patients, but it’s not as bad as you might think,” said Amador. “The needle is very thin and small, and many patients say they don’t even feel the injection. Some medications require an injection monthly, but newer therapies available today allow even more time between injections.”
Silva said that these drugs have led to the best outcomes for people with retinopathy or DME, and that the monthly treatment interval can be extended over time.
Some of these medications, known as anti-VEGF drugs, include Eylea (aflibercept), Lucentis (ranibizumab), and Beovu (brolucizumab-dbll).
Another medication, Vabysmo (faricimab-svoa), a newer drug approved in 2022, affects an additional disease pathway in the eye, along with the pathway of the anti-VEGF drugs above, and gives users the option to go up to four months between injections.
Laser treatments offer an alternative for those who want to avoid the injections. Silva explained that while a laser treatment is usually done only once or twice in a decade, these procedures may also shrink a person’s overall field of vision.
“Laser treatment provides long-term stability; however, injections provide better outcomes in terms of the visual field,” Silva said. “Any treatment for diabetic eye disease is a very personal decision, and anybody who needs treatment should work with their eye care provider to get the appropriate treatment for their situation.”
The panelists agreed that to prevent vision loss or amputations, the best thing people with diabetes can do is get screened.
“Blindness from diabetic eye disease is largely preventable,” Silva said. “Medical management of eye complications is more effective when people have early retinopathy. Managing diabetes and its associated conditions, with appropriate eye care, can reduce the risk for visual loss by over 96%.”
Isaacs encouraged those in the audience to advocate for these screenings and treatments, and said that nobody should feel shame or blame for experiencing one of these complications.
“Managing diabetes is hard work. We all know there are some people that do everything perfectly and still end up with complications, and vice versa, so there is an element outside of our control,” she said. “You, as the person with diabetes, are your best advocate. Attending programs like these, trying to stay up to date, and learning what’s out there – you can bring that back to your healthcare team.”