Background: The association between mean platelet volume (MPV) and mortality in patients with cardiovascular disease has been demonstrated. However, the association between MPV and mortality in peritoneal dialysis (PD) patients remains unclear.
Methods: Patients catheterized at the First Affiliated Hospital, Nanchang University, between November 1, 2005, and August 31, 2019, were enrolled. The primary endpoints were all-cause and cardiovascular mortality. Patients were divided into two groups according to the cutoff value, which was determined using maximally selected rank statistics. The mortality hazard ratio was evaluated using Cox regression models.
Results: Among the 1322 PD patients enrolled, the mean age was 49.3 ± 14.5 years, 57.6% were men, and 18.8% had diabetes. During a median follow-up of 50 months (IQR: 30-80), 360 patients died; among these, 167 deaths were attributed to cardiovascular diseases. Survival analysis revealed that all-cause and cardiovascular mortality rates were lower in the higher-MPV group than in the lower-MPV group (p < .001 and p < .001, respectively). After full adjustment, a higher MPV was significantly associated with a hazard ratio of 0.77 for all-cause mortality (95% CI: 0.60-0.98, p = .036) and 0.75 for cardiovascular mortality (95% CI: 0.51-0.97, p = .041). Subgroup analysis showed that a significant interaction existed between age and MPV (p < .001). Decreased MPV was associated with higher mortality risk only in patients < 60 years old.
Conclusions: Our results showed that lower MPV can be associated with a higher risk of all-cause and cardiovascular mortality in patients with PD.
Keywords: All-cause mortality; cardiovascular mortality; mean platelet volume; peritoneal dialysis; survival analysis.