A team of researchers analyzed a nationwide sample to identify predictors and trends in the incidence of transtibial and transfemoral amputations. They concluded that the incidence of major amputation has steadily increased since 2010, accompanied by a substantial shift in the patients’ comorbidity and demographic profile.
The researchers used the National Inpatient Sample from the Department of Health & Human Services’ Agency for Healthcare Research and Quality to identify inpatient admissions with a diagnosis of atherosclerosis and/or related amputation and multilevel logistic regression to identify amputation predictors over time.
Between January 1993 and December 2021 the research team identified 197,018 patients who underwent transtibial amputations and 151,018 who underwent transfemoral amputations.
Transtibial incidence decreased from 12/100,000 people in 1993 to 8/100,000 in 2010 (a 2.2 percent reduction per year). This trend reversed after 2010, ending in 13/100,000 in 2021 (a 9 percent increase per year).
The incidence of transfemoral amputation decreased from 11/100,000 people in 1993 to 6/100,000 in 2012 (a 2.1 percent reduction per year). This trend reversed in 2012, ending in 8/100,000 in 2021 (a 4 percent increase per year;).
The mean age for transtibial amputations decreased from 68 years in 1993 to 61.6 years in 2021. For transfemoral amputations, the mean age decreased from 75 years to 66.7 years.
The researchers also compared admissions for major amputations to 2,421,352 admissions for atherosclerosis that did not result in amputation. After 2010, transtibial amputation patients were more likely to be younger, white, obese, and hypertensive.
After 2012, transfemoral amputation patients were younger and less likely to be female. They showed shifts in effect size but not in the direction of important risk factors such as white race, hypertension, and obesity. Population attributable fractions confirmed a progressive shift in the effect of risk factors on the changing incidence of both types of amputation. The effect of other risk factors such as diabetes and dialysis remained unchanged over time.
The researchers suggested that treatment paradigms to address the serious public health issue need to be reconsidered to reflect increasing effects of metabolic syndrome.
The paper, “Turning tides: Evolving comorbidity profiles, demographic shift, and the unexpected rise of major lower extremity amputations,” was published in the Annals of Surgery.
