Abstract: Objective  To investigate vitamin levels of elderly patients with continuous ambulatory peritoneal dialysis and clinical significance of vitamin status, and to provide proper reference for nutritional intervention.  Methods  Totally, 242 patients undergoing continuous ambulatory peritoneal dialysis at Peritoneal Dialysis Center of Changhai Hospital from March 2019 to March 2021 were selected as subjects, with their age and sex recorded. The patients were divided into the elderly group and the non-elderly group. Vitamin levels and some other laboratory test results of these two groups were examined and compared. The correlation coefficient between vitamin levels and biochemical indicators of the elderly was also calculated.  Results  The serum creatinine levels (t=-6.989，P＜0.001), urea nitrogen levels (t=-2.044，P=0.042) and parathyroid hormone levels (t=-2.048，P=0.042) in the elderly group were lower than those in the non-elderly group. The levels of vitamin A (t=-2.629，P=0.009), vitamin B1(t=-2.115，P=0.035) and vitamin B9 (t=-2.250，P=0.025) in the elderly group were lower than those in the non-elderly group. Vitamin A (r=-0.223，P=0.036)and vitamin B6 levels (r=-0.270，P=0.011) were negatively correlated with age. Vitamin C (r=0.421，P＜0.001)and vitamin E (r=0.265，P=0.013)levels were positively correlated with hemoglobin levels. Vitamin B9 levels were positively correlated with triglyceride levels (r=0.218，P=0.042). And vitamin B2 levels were positively correlated with ferritin levels (r=0.217，P=0.043). The deficiency rates of vitamin A (χ2=5.826，P=0.016), vitamin B2 (χ2=20.823，P＜0.001) and vitamin B12 (χ2=8.150，P=0.004) in the elderly group were significantly higher than those in the non-elderly group.  Conclusion Vitamin deficiency is common in elderly patients with peritoneal dialysis and vitamin levels are associated with some clinical tests and examination indicators. It is necessary to monitor the vitamin levels of elderly patients and supplement them in time.

Key words: The elderly, Peritoneal dialysis, Vitamin