Among patients with diabetic foot disease, the possibility of losing a foot or leg to amputation can be more frightening than other potential complications of the disease, including heart attack, stroke, dialysis, and even death.
Sadly, fear at the prospect of lower extremity amputation is not unfounded. Despite improvements in the management of some other complications of diabetes, the rate of amputations in the United States has increased in recent years. And there is a glaring disparity in amputations across racial, geographic, and socioeconomic lines.
Background
The prevalence of diabetes in the United States continues to increase. The American Diabetes Association (ADA) estimates that 37.3 million Americans, or 11.3% of the population, have diabetes, with the highest prevalence among American Indians/Alaska Natives (14.5%), people of Hispanic origin (11.8%), and non-Hispanic blacks (12.1%). The prevalence is lowest among Asian Americans and non-Hispanic Whites, at 9.5% and 7.4% respectively.
Uncontrolled, diabetes can impact nearly every organ system. The collective interplay of damages to the circulatory, nervous, and immune systems makes diabetics’ feet especially vulnerable. For the diabetic patient, the smallest of foot injuries—a nick during a pedicure, stepping on a mislaid toy, friction from a poorly fitting shoe—can lead to a life-threatening infection.
Diabetic neuropathy—damage to the peripheral nerves resulting from high glucose levels—can simultaneously affect the biomechanics or positioning of a patient’s foot, prevent a patient from feeling the initial formation of a resulting callus, and reduce natural sweating, making the skin drier and more vulnerable to tear or breakdown from friction.
Diabetes-related peripheral arterial disease can limit blood flow to legs and feet, while high glucose levels can reduce the body’s ability to fight off colonization by pathogens.
Diagnosed before an infection sets in, a diabetic foot ulcer may only require homecare. However, when a simple callus advances to osteomyelitis or gangrene, amputation may be indicated to stop the spread of infection.
Occurrence
According to the Centers for Disease Control and Prevention (CDC), there are annually 5.6 lower extremity amputations for every 1,000 adult diabetics. In a 2018 report, the American Diabetes Association (ADA) observed that, after two decades of decline in diabetes-related amputations, the favorable trend had ended and the rate of amputations was increasing among certain subsets of the diabetic population.
The risk of unhealing foot wounds and—more importantly—the risk of lower extremity amputation is not shared equally among diabetics. There are glaring disparities in the rates of both. In fact, the differences in the use of amputation across races, geographic regions, and economic classes are so extreme that Dean Schillinger, M.D., a professor of medicine at the University of California, San Francisco, has characterized them as a “mega-disparity.”
African American patients with diabetes-related foot ulcers and infections are statistically more likely than White patients to undergo amputations. In a cohort study of 124,487 patients published this year, researchers found that among patients hospitalized with diabetic foot ulcers, those identifying as Black were more likely than those identifying as White to undergo leg amputation or die.
Other researchers have found that Whites are less likely to undergo a lower extremity amputation than either Native Americans or Hispanics and that those living in rural areas or the South are more likely to have amputations than those in metropolitan areas or the Northeast.
Amputation rates are also greater among rural populations and the working poor. A 2014 study of amputations in California found that those living in wealthier ZIP codes were less likely to undergo amputations than those living in poorer neighborhoods
Even when clinically indicated and unavoidable, amputations bring with them an entirely new set of physical, sociological, and economic complications for patients and their families. Amputations are associated with restricted mobility, physical deconditioning, increased social isolation, and a higher rate of mortality. Healthy meal prep, adequate exercise, and keeping medical appointments—all essential elements of diabetes management—become more challenging after the loss of a leg or foot, or even the “minor” loss of a toe.
Political implications
Disparities in amputation rates are more than a medical issue. For many, they are confirmatory evidence of the influence of social determinants of health and the unequal distribution of the country’s healthcare resources.
For some, they have also become a social justice issue. In a May 2020 article entitled, the Black American Amputation Epidemic, the nonprofit ProPublica provided an overlay of maps showing the close alignment of the average rate of amputations for peripheral artery disease per 10,000 patients per year from 2007-2009 with the percentage of the population enslaved in 1860.
Both maps align with the CDC’s “diabetes belt,” a swath of the country incorporating 644 predominately rural counties in 15 states across Appalachia and the south characterized by higher risk of diabetes and limited access to healthcare.
Zoom out and, nationally, one finds a discouraging correlation between amputation rates and the Health Resources & Services Administration’s Health Provider Shortage Areas (HPSAs).
Like so many aspects of diabetes, the problem is multifaceted. Even if an individual has access to transportation and the time and motivation to seek diabetes screening, those living in HPSAs may not have access to primary care providers who can diagnose and help manage the disease. It is even less likely that a diabetic living in an HPSA will have access to a cardiologist who can diagnose and treat diabetes-related peripheral artery disease before it progresses.
The unequal distribution of specialists in the United States is neither arbitrary nor organic. As Applied Policy has previously noted, the structure of the nation’s graduate medical education program drove the initial concentration of medical specialists in the Northeast. Additionally, the Health Services Corps of the U.S. Department of Health & Human Services’ Health Resources & Services Administration is structured to encourage primary care provider participation in HPSAs but does not extend to specialty care.
Even when a patient does have access to specialty care, insurance reimbursement policies may not cover preventative screenings for peripheral artery disease. Restrictions on who can refer patients for care can postpone enrollment in critical self-management programs. This is also true for Medicare and Medicaid, even though 14% of Medicaid beneficiaries have diabetes. Additionally, coverage for continuous glucose monitors (CGMs) varies widely across Medicaid programs, meaning that a diabetic who qualifies for a CGM in one state might be ineligible in the next.
Fixing the problem
According to Lisa Murdock, chief advocacy officer for the American Diabetes Association, 85% of diabetic amputations are preventable. Yet, misconceptions on the part of providers and patients alike may limit critical referrals for screenings and the use of proven interventions, including diabetes self-management programs.
As Kate Thomas, chief advocacy and external affairs officer for the Association of Diabetes Care & Education Specialists observed, reducing diabetes-related amputations and disparities in the same will require the same “Attack from all fronts” approach needed for the disease itself.
This multi-prong approach will entail education, policy changes, legislation, and a sense of urgency.
There are several pieces of diabetes-specific legislation currently pending in Congress. The Amputation Reduction and Compassion (ARC) Act introduced by Rep. Donald Payne (D-NJ), a member of the bipartisan Congressional Peripheral Artery Disease Caucus, would establish coverage of peripheral artery disease screening tests for at-risk Medicare and Medicaid beneficiaries with no cost-sharing requirements.
The American Diabetes Association, which has found that diabetes patients who have an annual wellness exam are 36% less likely to experience an amputation, has called upon policy makers to do more to incentivize participation in annual wellness exams.