Ethnic Risk of Foot Ulceration

While diabetic foot ulceration affects a significant number of patients every year, certain ethnic groups are more susceptible than others, by virtue of their genetic predisposition. In this chapter, we shall attempt to establish the relevance of this risk factor and highlight how foot ulceration is more likely to occur among specific ethnic groups. An epidemiological study was conducted in the UK on 15,692 patients afflicted with Type 1 and Type 2 diabetes. The subjects were screened for neuropathy, foot ulceration, deformities, and peripheral arterial disease (PAD). A total of 85 percent of the respondents were European, 11.9 percent were South Asian, and 2.4 percent were of African-Caribbean ethnicity.

Results of the Study

The results indicated that Europeans had the highest risk of developing diabetic foot ulceration, while subjects of African-Caribbean ethnicity had a lower risk. South Asian subjects had the least risk of developing ulceration. The reduced foot ulcer risk was attributed to the lower incidence of several contributing factors, including PAD, insulin usage and neuropathy. The same was true of African-Caribbean subjects. Their lowered risk was attributed to a minimal risk of neuropathy. European subjects, on the other hand, displayed a three- to four-fold risk of developing ulceration due to their high incidence of all the major contributing factors.

Methodology of the Study

The North-West Diabetes Foot Care Study was conducted on subjects residing in the greater Manchester area, in the UK. The subjects were randomly selected from primary and secondary healthcare facilities by trained medical practitioners and were studied for a period of 4 years. A complete medical history of each patient was taken into account, along with a thorough physical examination detailing instances of past and present ulceration. The standard for foot ulceration was set as a complete break in the skin. The incidence of peripheral neuropathy among the subjects was evaluated using a variety of techniques. The severity of neuropathy was assessed using a pre-determined score, which assessed the presence and severity of various symptoms such as the ability to feel a pin-prick like sensation, the vibrations from a tuning fork, variations in temperature produced by cool and warm rods, and to produce the Achilles reflex using a tendon hammer.

Subjects with scores of less than 6 were considered to have low to severe neuropathy. Cutaneous pressure of the skin was assessed using the action of a 10g monofilament on the first and fifth toes, as well as the heels and metatarsals. Foot deformities such as muscle wasting, hammer and claw toes, bony prominences, and other anomalies were evaluated using a six-point deformity score. A score of less than 3 was taken as being indicative of Charcot arthropathy. The peripheral arterial status was gauged by palpating the sides and base of the feet. If the subjects registered a pedal pulse of strength two or less than the normal four, it was considered an indication of peripheral arterial disease. Additionally, a thorough record of the subject’s medical history, that included instances of angioplasty or bypass surgery, was taken into account.

Conclusions

After studying the subjects over a period of 4 years, researchers found that the prevalence of crude ulceration was the lowest in Asians, in contrast to Europeans and those of African-Caribbean ethnicity. The same was the case with respect to active foot ulceration, which was 2.3 times less prevalent among Asians as compared to Europeans. The incidences of lower extremity amputation were also strikingly lower among Asians in contrast to European and African-Caribbean subjects. Thus, it was concluded that, due to genetic and other lifestyle factors, people of Asian and African-Caribbean ancestry were less susceptible to developing diabetic foot ulceration and subsequent amputation. Europeans and people of European ancestry, on the other hand, are considered a high-risk group.

National Diabetes Statistics Report of

America

As per the National Diabetes Statistics Report released in 2014, 29.1 million Americans are afflicted with diabetes and an estimated 86 million have pre-diabetes. These figures were further divided up under racial and ethnic groups. The statistics revealed that 7.6 percent of non-Hispanic whites, 12.8 percent of Hispanics, 9 percent of Asian-Americans, 15. 9 percent of Native Americans and 13.2 percent of African-Americans were suffering from diabetes. Also, diabetes is the seventh leading cause of death in the United States.

Diabetes accounted for 73,000 cases of lower extremity amputation in 2010, and comprised 60 percent of all surgeries of this nature. Foot ulceration was established to be the leading cause of lower extremity amputation. From these figures it was recognized that patients with diabetes had a OR percent risk of developing a foot ulcer during their lifetime. Additionally, patients were at a greater risk of ulceration if they had not achieved adequate diabetes management, smoked, suffered from neuropathy or peripheral arterial disease, and had long periods of hyperglycemia. Patients with a history of previous ulceration were identified as having a continued high risk, as the recurrence rate of ulceration was as high as 35 percent within a span of one year, and 77 percent over a period of five years.

Racial and Ethnic Risk of Ulceration in

America

The report highlighted that diabetic patients belonging to various racial and ethnic groups experienced disproportionate rates of lower extremity amputation. A 2009 report showed that African-Americans had an amputation rate that was 50 percent higher than white Americans. According to Medicare data released in 2008, Native Americans also had an incidence rate that was double that of white Americans.

Recent research has attributed these disparities to the unavailability of cheap and affordable medical care for ethnic groups that belonged to the low-income strata. It was found that patients who typically resided in predominantly low-income neighborhoods displayed much higher rates of lower extremity amputation than those who lived in more affluent neighborhoods. This goes on to show that, due to socio-economic constraints, low income ethnic groups are unable to afford quality medical treatment, making them more prone to developing ulceration.

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