Serum asymmetric dimethylarginine, apelin, and tumor necrosis factor-α levels in non-obese women with polycystic ovary syndrome

► Serum ADMA and TNF-α levels were increased in non-obese women with PCOS. ► Serum apelin levels were decreased in non-obese women with PCOS. ► Non-obese women with PCOS have unfavorable serum markers for CVD. ► The risk markers for CVD are correlated with hyperandrogenism in non-obese PCOS.