Lower Limb Amputation is a devastating complication of diabetes and poor circulation (a.k.a peripheral artery disease) that can have a lasting impact on a person’s mobility, mental health and life expectancy. Amputation can be prevented through foot screening (regular examination and foot care) and timely limb preservation treatments when a foot complication arises.  Our research team has shown that the frequency of toe/foot/leg amputation has risen by 15% over the last decade; with 5 amputations every day in Ontario. There is striking regional variation in amputation rates and health services that influence amputation risk; with regional variation increasing over time. Rising diabetes prevalence has contributed to greater burden of disease. Fortunately, the COVID-19 pandemic saw a drop in limb loss. This work has helped justify and inform Ontario Health’s recently launched Lower Limb Preservation Strategy.

In 2019, the evolving clinical burden of limb loss secondary to diabetes and peripheral artery disease (PAD) was poorly quantified in Ontario, as were prevention efforts. Anecdotable evidence did suggest that the care necessary to prevent amputation from diabetes and PAD was inconsistent and disjointed. With the onset of the COVID-19 pandemic, there was also concern that deferred diabetic foot screening and delays in timely care of acute foot complications would contribute to an increase in limb loss related to diabetes.

APPROACH: Using administrative health data for the province of Ontario, we sought (i) to examine secular trends in the rates of toes/foot/leg amputations related to diabetes, peripheral artery disease or both, (ii) to characterize regional variation in leg amputation rates and explore the correlation between regional health care services received and rates of lower extremity amputation rates; (iii) to quantify the influence of rising diabetes prevalence on rates of leg amputation related to peripheral artery disease; (iv) to evaluate the association of the COVID-19 pandemic with diabetes-related care measures, foot complications, and leg amputation.

RESULTS: Toe/foot/leg amputations related to diabetes and/or peripheral artery disease increased from 2005-2016. There was wide regional variation in leg amputation rates across 14 historic LHINs: 2.53 to 11.77 per 100 000 person-quarters. At a regional level, lower extremity revascularization rates showed the strongest negative correlation with amputation rates. From 2002-2019, the extent of regional variation increased from moderate to large for leg amputation (standardized PRR, 1.94 to 3.07). A decrease in leg amputations related to PAD over time was attenuated by rising diabetes prevalence rates. After the onset of the COVID-19 pandemic, rates of leg amputation related to diabetes in 2020-2021 decreased compared with 2019-2020 levels.

CONCLUSION: These results have served to justify and inform Ontario Health’s Lower Limb Preservation Strategy (Lower Limb Preservation Strategy – CorHealth Ontario), currently being lauched at 11 demonstration sites (Ontario Haelth Teams) across the province.

• Advancing our understanding of the burden of limb loss related to diabetes and peripheral artery disease (PAD) in Ontario.
  10. Secular trends in amputation related to diabetes and PAD in Ontario – CMAJ 2019:191(35): E655–  DOI: https://doi.org/10.1503/cmaj.190134
  11. Four-fold difference in age- and sex-adjusted diabetes- and PAD-related amputation rates across administrative regions in Ontario (Can J Public Health 2019;110(2):253-255 DOI: https://doi.org/10.17269/s41997-018-0166-y)

• Temporal trends in hospitalization for lower extremity peripheral artery disease in Ontario (Can J Cardiology 2021;S0828-282X(21)00368-8 https://doi.org/10.1016/j.cjca.2021.07.004)

15056. Influence of diabetes on temporal trends in lower extremity revascularization and amputation for PAD in Ontario (Diabetic Medicine 2023;40(6):e15056. https://doi.org/10.1111/dme.15056)
15057. Regional variation in lower extremity revascularization and amputation related to PAD in Ontario (J Vasc Surg 2023;77(4):1127-1136 https://doi.org/10.1016/j.jvs.2022.12.032)
15058. Decrease in rate of leg amputations related to diabetes in the first 11 months of the COVID-19 pandemic in Ontario- (JAMA Network Open. 2022;5(1):e2142354 https://doi.org/10.1001/jamanetworkopen.2021.42354)

• Advancing our understanding of the delivery and impact of preventative care.
  10. Regional amputation rates are inversely correlated with regional lower extremity revascularization rates and access to chiropody in Ontario. (CMAJ Open 2020; 8(4):659-66 https://doi.org/10.9778/cmajo.20200048).

• Advancing the foundations of health services research using administrative health data with respect to amputation prevention.
  10. Validated administrative data procedure coding for lower extremity revascularization in Ontario (Clin Invest Med. 2021;44(2):E36-43 https://doi.org/10.25011/cim.v44i2.36354).
  11. Demonstrated the importance of considering diabetic-specific ICD-10 diagnoses codes when using administrative health data to study the epidemiology of PAD in Canada (Can J Cardiology 2021;S0828-282X(21)00368-8 https://doi.org/10.1016/j.cjca.2021.07.004).

Validated ICD-10 diagnostic codes for the identification of hospitalization related to diabetic foot ulceration (Clin Invest Med. 2021;44(4):E11-16 https://doi.org/ https://doi.org/10.25011/cim.v44i4.37592).