MP612SELF-REPORTED PHYSICAL ACTIVITY, QUALITY OF LIFE, AND PSYCHOLOGICAL STATUS IN RELATION TO PLASMA 25-HYDROXYVITAMIN D CONCENTRATION IN PREVALENT HEMODIALYSIS PATIENTS

Abstract

Introduction and Aims: Vitamin D is announced among factors that may influence physical performance and mental health. The objective of this study was to evaluate self-reported physical activity, quality of life, psychiatric functioning, and affects with respect to plasma vitamin D concentrations in prevalent hemodialysis (HD) patients. Methods: The study was carried out in autumn in 112 HD patients not receiving vitamin D supplements. The group (age 68.0, 29.0 - 91.5 years, renal replacement therapy vintage 4.82, 1.96 - 21.0 years, 65 patients on high-flux HD) included 53 women, 34 patients with type 2 diabetic nephropathy, and 33 subjects with coronary artery disease. Plasma concentration of 25-hydroxyvitamin D [25(OH)D] was measured by a chemiluminescent microparticle immunoassay. Physical activity was measured with the long version of the International Physical Activity Questionnaire (IPAQ-L). The Ferrans & Powers' Quality of Life Index - Dialysis Version III (QLI-D), General Health Questionnaire (GHQ-28), and The Positive and Negative Affect Schedule (PANAS) were employed to measure quality of life and associated mental health. Linear regression was used to determine associations among 25(OH)D concentration, psychological characteristics, and patient data. Multivariate analyses were used to exclude confounding variables among 29 parameters including demographic, genetic, clinical, and laboratory data. Results: Plasma 25(OH)D was suboptimal in all HD patients (14.6 ± 4.1 ng/mL). Adjusted determinants of 25(OH)D concentration included the GG genotype of GC rs7041 (β ± SE: 1.77 ± 0.70, P = 0.014), female sex (β ± SE: -2.19 ± 0.75, P = 0.004), and treatment with high flux HD (β ± SE: 2.59 ± 0.69, P = 0.0003). By IPAQ, none of the HD patients was working or performing vigorous-intensity activities. Transport-related activity was revealed in 44 (39.3%) patients, leisure-time activity was reported by 35 (31.3%), and housework and gardening activity was shown in 25 (22.3%) patients. In respect to forms of physical activity, walking was reported by 45 (40.2%) subjects, and moderate-intensity activities were performed by 39 (34.8%) subjects. As many as 45 (40.2%) patients did not report any physical activity in terms of asked questions. In adjusted analyses, circulating 25(OH)D was revealed as a significant positive determinant of “total domestic and gardening physical activity” domain (β ± SE: 53.2 ± 23.8, P = 0.028). In terms of intensity, a significant impact of vitamin D was shown on total moderate-intensity activities (β ± SE: 54.9 ± 27.4, P = 0.048). Quality of life, psychiatric functioning, and affects were not significantly associated with circulating 25 (OH)D concentrations. All these latter domains were negatively influenced by type 2 diabetic nephropathy as a cause of end-stage renal disease. Conclusions: Vitamin D [25(OH)D] is a meaningful positive contributor to physical activity in HD patients. Quality of life and mental health do not seem to be differentially influenced by suboptimal levels of circulating 25(OH)D.