Simple Foot Risk Score Shows Striking Accuracy in Spotting Diabetic Ulcers

Every twenty seconds, somewhere in the world, a person with diabetes loses a leg. Behind that statistic sits a quieter one: the vast majority of those amputations begin as a small, seemingly innocuous foot ulcer that nobody flagged in time. Now a study of 713 patients in Saudi Arabia offers fresh evidence that a simple, decades-old risk scoring system can sort the vulnerable from the safe with almost uncanny precision — and that the answer to who is at risk lies not in a patient’s sex, but in their age and their blood sugar.

The research, published in the journal Diabetes Therapy, examined the International Working Group on the Diabetic Foot (IWGDF) risk stratification system, a framework that sorts people with diabetes into four categories — very low, low, moderate, and high risk — based on whether they have lost protective sensation in their feet, whether they have peripheral artery disease, whether their feet are deformed, and whether they have ever had an ulcer or amputation before. The system is the backbone of diabetic foot screening worldwide, yet its real-world performance in specialist clinics, particularly in the Middle East, had remained thinly documented.

The team, led by Fatimah Z. Alenazi of Qassim University, analyzed clinical records from consecutive adults attending the diabetic foot service of the Abdullah Al-Othaim Diabetes Center in Buraydah between November 2025 and June 2026. The cohort comprised 373 men and 340 women, overwhelmingly with type 2 diabetes, with a mean age of 57.6 years and an average glycated hemoglobin (HbA1c) of 7.82 percent. Because every patient under follow-up at the center is routinely scheduled for foot screening regardless of symptoms, the researchers argue the sample reflects ordinary specialist practice rather than a cherry-picked group of problem feet.

The headline result is a gradient so steep it borders on dramatic. Not a single active ulcer was found among the 335 patients classified as very low risk. Prevalence crept up to 0.8 percent in the low-risk group, 4.8 percent in the moderate-risk group, and then leapt to 38.5 percent among the 39 patients in the high-risk category — more than one in three. The trend across ordered categories was highly significant, with a Cochran–Armitage test statistic of 10.02 and a p value below 0.001, meaning the probability of such a smooth staircase arising by chance is vanishingly small.

Quantified as a single number, the system’s cross-sectional discrimination for detecting a prevalent active ulcer was a c-statistic of 0.938, a value approaching the theoretical ceiling of 1.0. At the moderate/high-risk threshold, the classification caught 90.5 percent of all active ulcers while carrying a negative predictive value of 99.7 percent — in plain terms, if a patient was told their risk was low, the odds they had a hidden ulcer at that moment were roughly one in three hundred. Tightening the criterion to the high-risk category alone pushed specificity to 96.5 percent and the positive predictive value to 38.5 percent, at the cost of sensitivity dropping to 71.4 percent, a trade-off clinicians can calibrate depending on available resources.

Overall, 2.9 percent of the cohort — 21 patients — arrived with an active diabetic foot ulcer, a figure consistent with the lower range reported in specialist clinics and below the global pooled point prevalence of roughly 6.3 percent. Men carried a numerically higher burden, at 3.8 percent versus 2.1 percent in women, echoing international cohorts in which male sex is repeatedly linked to ulceration and amputation. But the difference did not reach statistical significance, and the study’s 21 ulcer events leave limited power to rule out a real gap.

The more provocative finding emerged from the multivariable logistic regression. After adjusting for age, sex, and diabetes type, each additional year of age raised the odds of moderate/high IWGDF risk by about 4 percent, and each 1 percent rise in HbA1c raised those odds by 13.2 percent. Gender, by contrast, was statistically invisible: the adjusted odds ratio for women was 1.048, with a confidence interval spanning unity and a p value of 0.819. In a region where sex differences in care-seeking and footwear habits are often invoked to explain foot disease patterns, the data suggest the risk machinery itself does not discriminate by sex — age and glycemic control do the heavy lifting.

The biology behind the HbA1c signal is well understood. Chronic hyperglycemia drives the formation of advanced glycation end-products, fuels oxidative stress, and degrades both nerves and microvessels. The result is a foot that cannot feel a pebble in a shoe and cannot perfuse a wound once it forms — the classic pairing of neuropathy and peripheral artery disease that turns minor trauma into a non-healing ulcer. Elevated plantar pressures from obesity add a further mechanical insult, though body mass index was not systematically recorded in this registry and could not be modeled.

The study’s authors and independent commentators alike are careful about what the numbers do and do not prove. Because the design is cross-sectional, the c-statistic quantifies how well the system identifies ulcers that already exist, not how well it predicts ulcers that will appear next year — although prior external validation studies have shown the IWGDF categories do forecast future ulceration and amputation, with risk rising progressively across categories. The exploratory model for active ulceration itself, with only 21 events, yielded directionally similar associations for age and HbA1c but nothing statistically significant, and the researchers flag it as underpowered and vulnerable to overfitting.

Even with those caveats, the practical implications are immediate. Vascular assessment with ankle–brachial index or pulse-volume recording was documented in 90.2 percent of patients, demonstrating that structured screening can be nearly complete in routine care. The findings support concentrating specialist podiatry and vascular resources on the 17.3 percent of patients classified at moderate or high risk — a subgroup that accounted for a disproportionate share of prevalent disease — while reassuring the majority that their short-term ulcer risk is minimal. For national diabetes programs in Saudi Arabia and beyond, where amputation rates remain among the highest regionally, the message is that a monofilament, a Doppler probe, and a disciplined scoring habit may be the cheapest amputation-prevention technology medicine has.

Subject of Research: Clinical Performance of the IWGDF Risk Stratification System for Diabetic Foot Ulceration: A Gender-Disaggregated Study of 713 Patients

Article Title: Clinical Performance of the IWGDF Risk Stratification System for Diabetic Foot Ulceration: A Gender-Disaggregated Study of 713 Patients

Article References: Alenazi, F. Z., Alslamah, T., Alharbi, B., Alotaibi, W. I., Algeffari, M., Alsalamah, Y. S., Almohaileb, F. I., Fawaz, M. A., & Raposo, A. (2026). Clinical Performance of the IWGDF Risk Stratification System for Diabetic Foot Ulceration: A Gender-Disaggregated Study of 713 Patients. Diabetes Therapy. https://doi.org/10.1007/s13300-026-01925-w

Image Credits: AI Generated

DOI: 10.1007/s13300-026-01925-w

Keywords: diabetic foot ulcer, IWGDF risk stratification, diabetes complications, HbA1c, peripheral neuropathy, Saudi Arabia, foot screening, peripheral artery disease, Clinical, Performance, IWGDF, Risk