Rosamund James BSc(Hons) MRCPod-Podiatrist
Many people with diabetes say, “I have poor circulation”. They could mean that they have varicose veins/venous insufficiency, or they mean they have reduced blood flow to the feet, known as peripheral arterial disease (PAD). Both of these have an increased incidence in people with diabetes.
Circulating blood flow occurs in arteries, which carry blood from the heart to the whole body, and veins, which carry blood away from tissues back to the heart. PAD means that the tissues of the feet receive less arterial blood flow, and therefore, there is a reduction of all the nutrients that keep the feet healthy.
Adequate blood circulation (perfusion) to the feet allows wounds to heal well and creates well-hydrated skin and nails, which are less likely to be dry and cracked. Signs of reduced arterial perfusion in PAD include changes in skin colour (dark pigmentation is common), cool, shiny, thin skin, slow-healing wounds or pain in the calves when walking.
Podiatrists and other health care professionals may assess the perfusion to your feet in clinic or refer you to a vascular lab. A doppler ultrasound (Picture 1) can be used to determine a value known as the ankle-brachial pressure index (ABPI). This value should be between 0.9 and 1.3. A value below 0.9 and above 1.3 suggests that disease processes are starting in the arteries.
There is an increased risk of PAD if you have one or more of the following:
- Elevated HBA1C (7 % and below is preferable)
- Uncontrolled hypertension
- High cholesterol
- Smoker (nicotine or marijuana)
These risk factors can contribute to the narrowing of the arteries by increased plaque deposition. The narrower the artery, the more the blood struggles to get to where it needs to go. You will appreciate that the feet are far away from the heart and, therefore, very vulnerable to poor perfusion.
It is important to detect PAD at an early stage so the risk factors can be reduced before they can compromise the health of your feet. It should be highlighted that if PAD is diagnosed, there is an increased likelihood of reduced perfusion to other parts of the body, such as the heart or brain. This is why assessment of foot arterial blood flow is an essential part of your yearly diabetic foot screen.
You can maintain the perfusion to your feet to prevent or slow down the progress of PAD by addressing the risk factors:
- Smoking cessation is vital.
- Attending your doctor’s appointments to make sure your blood pressure, blood glucose and cholesterol are within normal limits is equally important.
- Exercise can increase the blood flow to your feet. Thirty minutes or more of walking three to five times every week can actually create more arterial flow to your feet, and this is one of the best treatments for peripheral arterial disease.
If you have been diagnosed with PAD, prevention of injury and infection to your feet is crucial. Podiatry management can help prevent injury when trimming nails and provide early detection and management of foot problems. Your podiatrist will advise on protective footwear for indoors and outdoors, as well as give recommendations on the fit and features of those walking shoes which you will need to maintain healthy arteries!
