Regional variation in lower extremity revascularization and amputation for peripheral artery disease

Objective — To quantify the recent and historical extent of regional variation in revascularization and amputation for peripheral artery disease (PAD).

Methods — This was a repeated cross-sectional analysis of all Ontarians aged 40 years or greater between 2002 and 2019. The co-primary outcomes were revascularization (endovascular or open) and major (above-ankle) amputation for PAD. For each of 14 healthcare administrative regions, rates per 100,000 person-years (PY) were calculated for 6-year time periods from the fiscal years 2002 to 2019. Rates were directly standardized for regional demographics (age, sex, income) and comorbidities (congestive heart failure, diabetes, chronic obstructive pulmonary disease, chronic kidney disease). The extent of regional variation in revascularization and major amputation rates for each time period was quantified by the ratio of 90th over the 10th percentile (PRR).

Results — In 2014-19, there were large differences across regions in demographics (rural living [range 0-39.4%], lowest neighborhood income quintile [range 10.1-25.5%]) and comorbidities (diabetes [range 14.2-22.0%], chronic obstructive pulmonary disease [range 7.8-17.9%]) and chronic kidney disease [range 2.1-4.0%]. Standardized revascularization rates ranged across regions from 52.6.2 to 132.6/100,000 PY and standardized major amputation rates ranged from 10.0 to 37.7/100,000 PY. The extent of regional variation was large (PRR≥2.0) for both revascularization and major amputation. From 2002-04 to 2017-19, the extent of regional variation increased from moderate to large for revascularization (standardized PRR=1.87 to 2.04) and major amputation (standardized PRR=1.94 to 3.07).

Conclusions — Significant regional differences in revascularization and major amputation rates related to PAD remain after standardizing for regional differences in demographics and comorbidities. These differences have not improved over time.