From JAMA Armstrong, Tan, Boulton, and Bus, JAMA. 2023;330(1):62-75. doi:10.1001/jama.2023.10578
In diabetic foot disease, tissue loss,
ischemia, and infection frequently
overlap. However, one is frequently
more dominant than the other at
different times in the life cycle of an
acute-on-chronic event. Here, the
amount of tissue loss, ischemia, and
foot infection can be ordinally graded
to help predict outcome and assist in
communicating a plan of action.
a A higher score on the WIfI scale38 is
associated with lower extremity
amputation and morbidity and can
be used to determine the need for
revascularization. WIfI scores of 1, 2,
3, and 4 were associated with 1-year
amputation rates of 0%, 8%, 11%,
and 38%, respectively.39 See also
Figure 3.
Flowchart for patients with a diabetic foot ulcer based on assessment and
treatment of the wound, of ischemia,35,49 and of foot infection.7 Additional
detail on off-loading wounds,51 wound management,52 treatment of infection,7
and management of chronic limb threatening ischemia may be found in the
International Working Group on the Diabetic Foot guidelines35 and Global
Vascular Guidelines.49
a Grading based on the Wound, Ischemia, and Foot Infection (WIfI) classification
system. See also Figure 2.
b See also Tables 3, 4, and 5.
c See also Table 6.
Importance Approximately 18.6 million people worldwide are affected by a diabetic foot ulcer each year, including 1.6 million people in the United States. These ulcers precede 80% of lower extremity amputations among people diagnosed with diabetes and are associated with an increased risk of death.
Observations Neurological, vascular, and biomechanical factors contribute to diabetic foot ulceration. Approximately 50% to 60% of ulcers become infected, and about 20% of moderate to severe infections lead to lower extremity amputations. The 5-year mortality rate for individuals with a diabetic foot ulcer is approximately 30%, exceeding 70% for those with a major amputation. The mortality rate for people with diabetic foot ulcers is 231 deaths per 1000 person-years, compared with 182 deaths per 1000 person-years in people with diabetes without foot ulcers. People who are Black, Hispanic, or Native American and people with low socioeconomic status have higher rates of diabetic foot ulcer and subsequent amputation compared with White people. Classifying ulcers based on the degree of tissue loss, ischemia, and infection can help identify risk of limb-threatening disease. Several interventions reduce risk of ulcers compared with usual care, such as pressure-relieving footwear (13.3% vs 25.4%; relative risk, 0.49; 95% CI, 0.28-0.84), foot skin measurements with off-loading when hot spots (ie, greater than 2 °C difference between the affected foot and the unaffected foot) are found (18.7% vs 30.8%; relative risk, 0.51; 95% CI, 0.31-0.84), and treatment of preulcer signs. Surgical debridement, reducing pressure from weight bearing on the ulcer, and treating lower extremity ischemia and foot infection are first-line therapies for diabetic foot ulcers. Randomized clinical trials support treatments to accelerate wound healing and culture-directed oral antibiotics for localized osteomyelitis. Multidisciplinary care, typically consisting of podiatrists, infectious disease specialists, and vascular surgeons, in close collaboration with primary care clinicians, is associated with lower major amputation rates relative to usual care (3.2% vs 4.4%; odds ratio, 0.40; 95% CI, 0.32-0.51). Approximately 30% to 40% of diabetic foot ulcers heal at 12 weeks, and recurrence after healing is estimated to be 42% at 1 year and 65% at 5 years.
Conclusions and Relevance Diabetic foot ulcers affect approximately 18.6 million people worldwide each year and are associated with increased rates of amputation and death. Surgical debridement, reducing pressure from weight bearing, treating lower extremity ischemia and foot infection, and early referral for multidisciplinary care are first-line therapies for diabetic foot ulcers.
