Association between statin therapy and amputation-free survival in patients with critical limb ischemia in the CRITISCH registry
Secondary prevention in patients with critical limb ischemia (CLI) is crucial for the reduction of cardiovascular morbidity and mortality. Nonetheless, current recommendations are extrapolated from other high-risk populations because of the lack of CLI-dedicated trials. The aim of this explorative study was to evaluate the association of statin therapy with the outcomes of CLI patients.Methods
The First-Line Treatments in Patients With Critical Limb Ischemia (CRITISCH) registry is a prospective multicenter registry analyzing the effectiveness of all available treatment strategies in 1200 CLI patients. For the purposes of this analysis, patients were divided into two groups based on statin administration. Treatment crossovers and nonadherent patients were excluded from analysis. The primary composite end point of this study was the amputation-free survival (AFS). Major adverse cardiovascular and cerebral events (MACCEs), time to death, and time to major amputation were also analyzed.Results
Statin therapy was applied in 445 individuals (37%), 371 (31%) patients received no statins, and 384 subjects were excluded from analysis (treatment crossovers). Patients receiving statins were more likely to be younger (P < .001) and to have a history of coronary heart disease (P < .001) or previous intervention at index limb (P < .001). Patients receiving statin therapy had a lower hazard regarding AFS (hazard ratio [HR], 0.45; 95% confidence interval [CI], 0.34-0.63; P < .001) and death (HR, 0.40; 95% CI, 0.24-0.66; P < .001) as well as lower odds of MACCE (odds ratio, 0.41; 95% CI, 0.23-0.69; P = .001). However, statin therapy was not associated with reduced amputation rates (HR, 1.02; 95% CI, 0.67-1.56; P = .922). Statin effect on AFS was consistent among diabetics (HR, 0.47; 95% CI, 0.31-0.70; P < .001), patients with chronic kidney disease (HR, 0.53; 95% CI, 0.32-0.87; P = .012), and patients older than 75 years (HR, 0.40; 95% CI, 0.26-0.60; P < .001). Statin administration was also associated with an improved AFS in patients with antiplatelet medication (HR, 0.64; 95% CI, 0.41-0.99; P = .049) and without antiplatelet medication (HR, 0.26; 95% CI, 0.12-0.57; P = .001) and after both endovascular therapy (HR, 0.51; 95% CI, 0.34-0.76; P = .001) and bypass revascularization (HR, 0.38; 95% CI, 0.21-0.68; P = .001).Conclusions
Statin therapy in CLI patients is associated with an increased AFS and lower rates of mortality and MACCEs without improving, however, the salvage rates of the affected limb.