History of lower-limb complications and risk of cancer death in people with type 2 diabetes

BACKGROUND: Individuals with diabetes and lower-limb complications are at high risk for cardiovascular and all-cause mortality, but uncertainties remain in terms of cancer-related death in this population. We investigated this relationship in a large cohort of people with type 2 diabetes. METHODS: We used data from the Action in Diabetes and Vascular Disease: PreterAx and DiamicroN Modified-Release Controlled Evaluation (ADVANCE) study. The primary outcome was adjudicated cancer death; secondary outcomes were overall and site-specific incident cancers, determined according to the International Classification of Diseases Code (ICD-10). We compared outcomes in individuals with (versus without) a baseline history of lower-limb complications (peripheral artery disease (PAD) or sensory peripheral neuropathy) using Cox regression models. RESULTS: Among 11,140 participants (women 42%, mean age 66 years), lower-limb complications were reported at baseline in 4293 (38%) individuals: 2439 (22%) with PAD and 2973 (27%) with peripheral neuropathy. Cancer death occurred in 316 (2.8%) participants during a median of 5.0 (25th–75th percentile, 4.7–5.1) years of follow-up corresponding to 53,550 person-years and an incidence rate of 5.9 (95% CI 5.3–6.6) per 1000 person-years. The risk of cancer death was higher in individuals with (versus without) lower-limb complication [hazard ratio 1.53 (95% CI, 1.21–1.94), p = 0.0004], PAD [1.32 (1.02–1.70), p = 0.03] or neuropathy (1.41 (1.11–1.79), p = 0.004], adjusting for potential confounders and study allocations. PAD, but not neuropathy, was associated with excess risk of incident cancers. CONCLUSIONS: PAD and peripheral neuropathy were independently associated with increased 5-year risk of cancer death in individuals with type 2 diabetes. PAD was also associated with increased risk of incident cancers. Our findings provide new evidence on the non-cardiovascular prognostic burden of lower-limb complications in people with type 2 diabetes.