Design: National population cohort, linked hospital and mortality records, 25 years
Population: 25,176 people with diabetes undergoing 28,232 below-knee amputations in England
Primary outcome: All-cause mortality
Effect: 23.5% at 1 year, 60.0% at 5 years, 82.3% at 10 years; no improvement since 2012

This was a national population study using linked Hospital Episode Statistics for England over 25 years. It followed 25,176 people with diabetes through 28,232 below-knee amputations, with all-cause mortality by Kaplan-Meier analysis as the primary outcome.

Mortality was 23.5% at one year, 60.0% at five years and 82.3% at ten, and the curve has not shifted since 2012. Older age, female sex and higher Charlson comorbidity score were each independently associated with higher mortality. Within 90 days, about one in five people was readmitted, 6.2% needed reoperation and 3.7% had a myocardial infarction. By five years, 6.4% had lost the other leg below the knee or above.

For the clinic, these are the numbers to have ready when counselling a patient and family before amputation, and a reminder that the amputation is a marker of systemic vascular disease, not the end of the problem. The contralateral foot needs the same surveillance as before, and secondary cardiovascular prevention deserves the same intensity as after a heart attack.

Quote about one-in-four one-year mortality when counselling before below-knee amputation in diabetes.
Put the remaining foot on high-risk surveillance from the day of surgery.
Review statin, antiplatelet and blood pressure treatment after amputation as for established cardiovascular disease.
Plan for readmission: about one in five returns to hospital within 90 days.
Older women with heavy comorbidity carried the highest mortality in this cohort.

Why it matters

Fifteen years of better diabetes care have not moved survival after major amputation, so the gain has to come from preventing it.

The statistics, in plain English

The 82.3% ten-year figure is a Kaplan-Meier estimate: of people who had the amputation, about eight in ten were expected to have died by ten years. A hazard ratio of 1.06 for women means a 6% higher death rate at any point than men after adjustment; the interval (1.03 to 1.10) is narrow because the cohort is large, but the effect is modest. These are associations from routine data, so they describe risk rather than explain it.