How Diabetes Can Sabotage Circulation

Diabetes is a disease involving body-wide vulnerability. By disrupting circulation, diabetes causes insidious damage to blood vessels that feed the limbs, heart, kidneys, brain and eyes. With reduced blood flow over time, worst-case scenarios include foot and leg amputation, kidney failure, heart disease and blindness.

Fortunately, if you're diagnosed with Type 2 diabetes, there's a lot you can do to help preserve circulation and stay as healthy as possible. Below, a vascular surgeon talks about procedures to restore circulation while a diabetes specialist encourages early prevention to keep surgery at bay.

[See: Got Diabetes? Why You Must Protect Your Feet.]

Diabetes Damage

Severely reduced blood flow to the legs and feet is the most common circulatory effect of diabetes seen by Dr. Gregory Moneta, a professor and chief of vascular surgery at Oregon Health and Science University Knight Cardiovascular Institute. His team's goal is to restore vein function and avoid the need for amputation of toes, feet and lower or sometimes even upper legs.

Using healthy veins to replace diabetes-damaged leg veins is a way to restore circulation, with procedures known as revascularization. "We try to use the patient's own vein -- the same vein you use for heart bypass," Moneta says. "Or we try to open native arteries in their legs with catheters and balloons -- whichever is most appropriate for the individual patient." It's basically about "plumbing," he says, although the plumbing can be complicated.

Unfortunately, lower limbs can't always be saved. Sometimes more invasive surgery is needed, with amputation as a last resort. Amputation rates among people with diabetes are declining. In 1996, the age-adjusted rate was nine cases for every 1,000 people with diabetes, according to the Centers for Disease Control and Prevention. By 2009, that figure had dropped to 3.2 cases.

"It's still a very significant number," Moneta says. "Most are them are below the knee, but some are above the knee." The point where salvage is no longer possible is when there's too much tissue loss or ischemia -- too little blood flow, he says. A gangrene infection of the foot can be too advanced for antibiotics to work.

An insignificant-seeming foot sore can provide an opening for bacteria. "Once bacteria get in there, they just start growing rapidly and cause destruction of the foot," Moneta says. "It's almost like an iceberg. What you see on the surface is a small amount compared to what's going on underneath."

Several diabetes hallmarks conspire to wreak havoc from bunions, ulcers and cracked skin in the feet and legs. Poor blood circulation reduces the body's wound-healing power. Nerve damage from diabetes reduces sensations of pain or irritation that could have signaled a problem earlier. Vision loss from poor circulation means people don't always see well enough to inspect their feet for skin fissures.

Diabetes also affects the major arteries, like the carotid arteries that supply blood to the brain. "That's another procedure we do with these patients -- clean out their carotid arteries to prevent stroke," Moneta says. Coronary arteries of the heart, also affected by diabetes, may require the services of heart surgeons. Small arteries of the kidneys can be compromised, too. "Some patients lose their kidney function and end up on dialysis," he says. That's when his team puts grafts in patients' arms to allow dialysis access.

[See: The 12 Best Diets for Your Heart.]

Embracing Early Prevention

To safeguard circulation, it's important to motivate patients to monitor and manage blood sugar, blood pressure and cholesterol, says Dr. Kevin Pantalone, an endocrinologist with the endocrinology, diabetes and metabolism department at Cleveland Clinic. "We need to empower patients early, as soon as they're diagnosed, to understand why we're making such a big deal" of these areas, he says.

"When you're diagnosed with Type 2 diabetes, studies have suggested you've already lost 50 to 80 percent of your body's ability to produce insulin," Pantalone explains. "So at the time of diagnosis, you are already behind the eight ball." Patients can counter threats to circulation by staying on top of their health care regimen and embracing a healthier lifestyle as follows:

Start right away. Making changes while you still have that remaining ability to control blood sugar is essential, Pantalone says. By waiting years to lose weight, for instance, even dropping 50 pounds won't allow patients to get off medication or make much of a difference, he says, "because they simply don't have the insulin-producing power left."

Stop smoking, stat. "Smoking and diabetes is a horrible combination," Moneta says. "It's a bit of an exaggeration, but you might as well just shoot the blood vessel -- you're going to kill it by smoking." It's challenging to quit smoking, so don't hesitate to get help from your doctor, cessation aids, "quit lines" and counseling.

Check feet. "We pay very close attention to the feet when patients come in for office visits," Pantalone says. "Checking their circulation; making sure there are no ulcers or cuts." Diabetic shoes are one way to help reduce pressure points and the risk of injuries. Between visits, it's up to patients and caregivers to routinely check feet from top to bottom. "Things can get out of control in a matter of days to weeks from a lesion they have on their foot if they don't notice it," he says.

Keep up with eye exams. "The small blood vessels of the eyes [when damaged] can cause retinopathy and blindness," Pantalone says. "That's why we do dilated eye exams on patients every year. Because their vision may be OK, but the eye doctor can see that the diabetes is starting to affect the small blood vessels of the retina, and they can do something to treat it to prevent things from getting worse."

Control blood sugar, blood pressure and cholesterol. The longer you have diabetes, the more even small elevations in these levels can add up to harm circulation. For each, medication is part of the program when lifestyle changes aren't enough.

Don't skip lab tests. You may feel fine, but your urine can pinpoint hidden problems like spilling protein. When your sample shows increased albumin, Pantalone says, that's a signal that health providers may need to treat and manage diabetes and blood pressure more aggressively.

[See: What Color Should My Pee Be?]

Eat right and exercise. Of course, that advice applies to everyone and even more so for people with diabetes. Maintaining good nutrition and a healthy weight, keeping a handle on portion sizes, cutting calories, avoiding sugary sodas and exercising at least 30 minutes a day, five days a week, can keep circulation humming and make all the difference between disability and a fully active life.

Lisa Esposito is a Patient Advice reporter at U.S. News. She covers health conditions, drawing on experience as an RN in oncology and other areas and as a research coordinator at the National Institutes of Health. Esposito previously reported on health care with Gannett, and she received her journalism master's degree at Georgetown University. You can follow her on Twitter, connect with her on LinkedIn or email her at lesposito@usnews.com.