Higher levels of matrix metalloproteinase-7 (log10MMP-7: 3.00±0.55 vs 2.78±0.55 pg/mL, p=0.046) and renin (log10renin: 3.27±0.59 vs 2.82±0.69 pg/mL, p<0.001), and greater proportion of patients with high levels of growth differentiation factor-15 (59% vs 37%, p=0.019) and tumour necrosis factor-receptor 2 (56% vs 34%, p=0.019) were seen in patients with diabetes compared with those without (figure 2, online supplemental tables 3 and 4). Here, REN is linked to diabetes mellitus.