AIMS: The aim of this study was to evaluate the temporal pattern of amputations in patients with type 2 diabetes mellitus (T2DM), the risk of amputations by new and older anti-diabetic drugs (ADDs), and the interplay of peripheral artery disease (PAD) with therapy and amputation risk.
METHODS AND RESULTS: Using Centricity Electronic Medical Records from USA, 3 293 983 patients with T2DM were identified: 169 739 received sodium-glucose cotransporter type-2 inhibitors (SGLT-2i; no exposure to incretins); 149 826 received glucagon-like peptide 1 receptor agonists [GLP-1RA, no SGLT-2i or dipeptidyl peptidase-4 inhibitor (DPP-4i) exposure]; 448 225 received DPP-4i (no exposure to GLP-1RA or SGLT-2i); and 1 954 353 received other ADDs. The proportion of incident amputations per 10 000 adults ranged between 4.7 and 6.8 during 2000-08 and significantly increased to 12.3 in 2017. Over 17 211 719 person-years follow-up post T2DM diagnosis, the rates per 1000 person-years of any and lower limb amputations (LLAs) were similar between SGLT-2i and incretins [95% confidence interval (CI) range: 1.06-1.67], and significantly higher in other groups (95% CI range: 1.96-2.29). In propensity score-adjusted pairwise analyses, the risk of LLA was not higher in SGLT-2i vs. GLP1-RA [hazard ratio (HR) (95% CI): 0.88 (0.73, 1.05)], and lower in SGLT-2i vs. DPP-4i/other ADD [HR (95% CI): 0.65 (0.56, 0.75)/0.43 (0.37, 0.49)]. The rate of LLA was similar in patients treated with canagliflozin, empagliflozin, or dapagliflozin. Patients with PAD had more than four-fold higher LLA risk (range of 95% CI of HR: 3.6-6.0).
CONCLUSION: The risk of amputation in patients treated with SGLT-2i and incretins was not higher compared with other ADDs. Pre-existing PAD was the greatest driver of amputation risk.
