Effect of vitamin D and resistance training on morphological, physiological, and cardio-inflammatory parameters in maintenance hemodialysis patients: randomized controlled trial

• Grant number: 17/13235-7
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2018
• End date: March 31, 2019
• Field of knowledge: Health Sciences - Nutrition
• Principal Investigator: Barbara Perez Vogt
• Grantee: Barbara Perez Vogt
• Host Institution: Faculdade de Ciências da Saúde (FCSA). Universidade do Oeste Paulista (UNOESTE). Presidente Prudente , SP, Brazil
• City of the host institution: Presidente Prudente
• Associated researchers: Fábio Santos de Lira

Abstract

Loss of muscle mass, muscle function and physical capacity are prevalent in patients with chronic kidney disease on hemodialysis and have an impact on the quality of life decrease and increase of mortality risk. Chronic systemic inflammation plays a role in these losses. These patients also present vitamin D deficiency, which leads to disturbances in bone mineral metabolism, and consequent reduction of Klotho expression, which is associated with the phenotype of premature aging. One of the characteristics of this phenotype is muscle mass and function decreases, which has been associated with vitamin D status in several populations. Trials with aerobic training showed serum Klotho increase. However, the effect of resistance training on Klotho has not yet been verified. Interventions aiming maintenance and/or improvement in muscle mass, physical capacity and muscular function need further investigation in patients with chronic kidney disease in dialysis therapy. Therefore, the objective of this study is to evaluate the effects of vitamin D supplementation and resistance training, isolated or associated, on morphological, physiological, cardio-inflammatory and biochemical parameters of maintenance hemodialysis patients. This is a two-arm clinical trial in hemodialysis: randomized, double-blind, placebo-controlled for vitamin D and randomized, open label and controlled for physical training. Patients older than 18 years on hemodialysis for at least three months will be included and those with positive exercise test for cardiac ischemia will be excluded. Patients will be randomized into one of the four groups, and will undergo the intervention for 16 weeks. Intradialytic resistance training will be performed three times a week lasting 40 minutes during the first two hours of the hemodialysis session. Vitamin D supplementation will be with cholecalciferol 50,000 IU/week. Body composition will be quantified by double energy X-ray absorptiometry. Bioelectrical impedance vector analysis will be done with the data provided by the multifrequency bioelectrical impedance test. Muscle function and physical capacity will be evaluated by handgrip strength and Short Physical Performance Battery. Inflammatory status will be assessed by serum cytokine concentration (leptin, adiponectin, IL-1ra, IL-6, TNF-±, and IL-10) and flow cytometry (sub-population of CD3, CD4 and CD8 T lymphocytes and subpopulation of CD14 and CD16 monocytes). Serum concentrations of phosphate, calcium, PTH and alkaline phosphatase, soluble Klotho and FGF-23 will be quantified for evaluation of bone mineral metabolism. (AU)