Prevalence and clinical impact of magnesium disorders in end-stage renal disease: a protocol for a systematic review.

BACKGROUND: Magnesium plays a key role in maintaining internal homeostasis through actions in the musculoskeletal, nervous, endocrine and cellular messenger systems. Renal excretion is the major route of magnesium elimination from the body. A positive magnesium balance would be expected in renal failure. However, a compensatory decrease in tubular reabsorption is expected to operate to maintain adequate urinary magnesium excretion even when glomerular filtration rate is very low. Patients with end-stage renal disease and those on dialysis have impaired regulatory mechanisms, predisposing them to disturbances in magnesium levels. The effects of high or low magnesium can have deleterious health outcomes, which impact on the co-morbidities and outcomes of chronic renal disease. This systematic review aims to determine the prevalence and clinical outcomes of magnesium disorders in end-stage renal disease.

METHODS/DESIGN: We will undertake a comprehensive search of various databases, MEDLINE, PubMED, EMBASE, Cochrane Library, Cochrane Collaboration, CIHNAL (Ebsco), Web of Science and Google Scholar, for observational studies and clinical trials on magnesium disorders in end-stage renal disease using key terms to identify papers for inclusion. Paper selection and data extraction (where appropriate) will be performed in duplicate on socio-demographic characteristics of participants, diagnosis of end-stage renal disease, magnesium levels, prevalence and clinical outcomes. An assessment of quality will be performed using a modified Newcastle-Ottawa Scale (NOS), including identification of any bias, which may influence findings. Data will be pooled together according to whether the studies were on pre-dialysis, hemodialysis or peritoneal dialysis participants. References from individual papers will also be screened as appropriate. Paper organisation and data extraction and analysis will take place using Microsoft Excel® and Stata version 13®.

DISCUSSION: This systematic review will represent a significant effort at pooling together information on prevalence and outcomes of magnesium disturbances amongst end-stage renal disease patients, which may guide further research and management of the disorders.

SYSTEMATIC REVIEW REGISTRATION: CRD42014014354.