APOA1 and peripheral arterial disease: Acylcarnitine ratio C4/C18:2 (β = 3.12 [0.09, 6.06], p = 0.04), ceramide ratio C24:1/C24:0 (β = 6.98 [4.03, 23.08], p = 0.02), history of peripheral artery disease (β = 2.98 [0.03, 8.48], p = 0.04), age (β = 3.00 [0.27, 5.06], p = 0.04), and ApoA1 (β= − 0.69 [− 1.41, − 0.12]; p = 0.03) were also independent predictors of CAD complexity in patients with CCS.