PTH and peripheral vascular disease: In the present investigation, we found that patients treated with convective or mixed techniques, online HDF in particular, showed significantly lower ALP serum levels than patients on conventional hemodialysis, after adjusting for confounding factors such as age, sex, Kt/V, Geriatric Nutritional Risk Index, vascular access, dialysis vintage, peripheral vascular disease, smoking, calcium, phosphorus, PTH serum levels.