Varying association of nutrient intakes with quality of life in patients receiving different modes of dialysis

Abstract

Background: Nutrients are crucial for dialysis patients, especially elderly patients. Nutrition-related complications in dialysis patients are often closely related to cardiovascular aging. However, we know little about the effect of different nutrients on the commonly used outcome predictor, health-related quality of life (HRQOL). Therefore, this study investigated the associations between different nutrients and HRQOL among dialysis patients.

Methods: A cross-sectional study was conducted on 123 dialysis adults at multiple dialysis centers. The Short Form-36 Health Survey (SF-36) assesses HRQOL. Modified quantitative subjective global assessment (MQSGA) evaluates nutritional status. A 3-day dietary record evaluated nutrient intakes.

Results: Among the 123 participants, 79 received hemodialysis (HD), and 44 were on peritoneal dialysis (PD). Patients with PD had a higher SF-36 score than HD (525 ± 136 vs. 375 ± 179, P < 0.001). A negative association between nutrition status and HRQOL was observed in HD (regression coefficient β = -17.4, P < 0.001) but not in PD (β = -12.3, P = 0.07). For HD patients, the nutrition status was negatively correlated with intakes of carbohydrates, fiber, selenium, copper, and Manganese (β = -0.02, P = 0.032; β = -0.3, P = 0.031; β = -0.1, P = 0.006; β = -2.3, P = 0.025; β = -1.3, P = 0.003, respectively). Their HRQOL was positively associated with calories, fat, niacin, and vitamin E (β = 2.19, P = 0.035; β = 2.4, P = 0.043; β = 8.5, P = 0.044; β = 6.9, P = 0.017, respectively). Conversely, for patients with PD, only vitamin B2 was found to be adversely correlated with their nutritional status (β = -5.2, P = 0.037), and increased intakes of vitamin A, vitamin C and fiber (β = 0.1, P = 0.031; β = 0.8, P = 0.028; β = 15.8, P = 0.045, respectively) were associated with a better HRQOL.

Conclusions: The nutritional intake of PD patients and HD patients affects their quality of life differently. Macronutrients significantly impact HRQOL in HD patients, while vitamins have a more substantial impact on PD patients.

Keywords: hemodialysis; malnutrition; nutrient; peritoneal dialysis; quality of life.

Figure 1

Scatter plots of SF-36 scores for patients receiving hemodialysis and peritoneal dialysis. HD, hemodialysis; PD, peritoneal dialysis.

Figure 2

Bar chart of the SF-36 subscale score in hemodialysis and peritoneal dialysis subgroup. The PF, SF, RE and MH subscale scores were significantly higher in peritoneal dialysis than in the hemodialysis subgroup. PF, physical functioning; RP, role-physical functioning; BP, bodily pain; GH, general health; VT, vitality; SF, social functioning; RE, role-emotional functioning; MH, mental health; HD, hemodialysis; PD, peritoneal dialysis. *** indicates a p value <0.001, ** indicates a p value < 0.05.

Figure 3

Moderator model for general health subscale in patients receiving peritoneal dialysis. Vitamin A, vitamin C, and calcium were all related to the general health subscale (β = 0.02, 95% CI: 0.00–0.04, p = 0.028; β = 0.1, 95% CI: 0.0–0.2, p = 0.015; β = 0.1, 95% CI: 0.0–0.1, p = 0.006, respectively). In addition, the interaction effects between vitamin A and calcium (c1), vitamin A and vitamin C (c2), vitamin C and calcium (c3) were also significant. c1, c2 and c3 represented the corresponding regression coefficients.