Background: Arterial stiffness is a major risk factor for cardiovascular and all-cause mortality in patients with end-stage renal disease. It has been reported that female and elderly diabetes mellitus (DM) patients treated with peritoneal dialysis (PD) had a higher risk of death. However, the underlying mechanism remains unknown. The present study tried to investigate whether older female DM patients have increased arterial stiffness. Methods: One hundred and eighty-one continuous ambulatory PD patients in a single center were enrolled. On enrollment, demographic data were collected. Carotid-femoral pulse wave velocities (PWV) were checked at the same time. Results: As expected, age had a significant impact on PWV both in DM and non-DM patients. There was no significant difference in PWV between male and female patients under the age of 50. No significant difference in PWV was found between male and female non-DM patients over the age of 50. However, the comparison of PWV reached statistical significance between male and female DM patients over the age of 50 (12.44 +/- 1.83 m/s vs. 13.56 +/- 1.86 m/s, p < 0.05). Conclusions: Our study showed that female DM patients over the age of 50 had the highest PWV as compared to other patient groups. Increased arterial stiffness might have contributed to the worst outcome of this population on PD treatment. Copyright (c) 2008 S. Karger AG, Basel