title: Hypophosphatemia: nutritional status, body composition, and mortality in hemodialysis patients.
abstract: OBJECTIVE
  The aim of the present study was to investigate the relationship between serum phosphate levels, clinical parameters, body composition, and mortality.
  
  
  METHODS
  Multicenter longitudinal observational study of a cohort of 3552 patients in hemodialysis (HD) from 34 Nephrocare dialysis units in Portugal with 24 months of follow-up. Patients were divided into three groups depending on their serum phosphorus (<3.5; 3.5-5.5; >5.5 mg/dL). Statistical tests were performed with SPSS, version 20.0. A p < 0.05 was considered significant.
  
  
  RESULTS
  On the one hand, hypophosphatemia was significantly associated with better dialysis adequacy, higher age and overhydration. On the other hand, it was associated with lower albumin, protein intake, creatinine, hemoglobin, calcium, potassium, magnesium, body mass index (BMI), body cell mass index, fat tissue index and lean tissue index. These patients had lower survival rates compared with those with normo- and hyperphosphatemia. Hypophosphatemia was a predictor of death when adjusted for age, diabetes, HD vintage, gender, and Kt/V. Comparing the mortality predictors in hypo- and hyperphosphatemia, we found that low albumin, BMI, and high overhydration increased the mortality risk in the hypophosphatemic group, whereas in hyperphosphatemic patients data were not statistically significant.
  
  
  CONCLUSIONS
  Currently, a high prevalence of hypophosphatemia exists in Portuguese HD patients. This condition is associated with worst nutritional and body composition parameters. In the context of additional indices of malnutrition (low albumin, low BMI or severe overhydration), hypophosphatemic patients presented higher mortality risk.
authors.affiliation: Nephrocare, Lisbon, Portugal. cgaragarza@hotmail.com.
authors.forename: Cristina
authors.initials: C
authors.lastname: Garagarza
authors.affiliation: Nephrocare, Lisbon, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Valente
authors.affiliation: Nephrocare, Lisbon, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Caetano
authors.affiliation: Nephrocare, Lisbon, Portugal.
authors.forename: Telma
authors.initials: T
authors.lastname: Oliveira
authors.affiliation: Nephrocare, Lisbon, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Ponce
authors.affiliation: Nephrocare, Faro, Portugal.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Silva
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D005260:Female; D006801:Humans; D054559:Hyperphosphatemia / Q000097:blood / Q000209:etiology / Q000401:mortality*; D017674:Hypophosphatemia / Q000097:blood / Q000209:etiology / Q000401:mortality*; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D010758:Phosphorus / Q000097:blood*; D011174:Portugal / Q000453:epidemiology; D011379:Prognosis; D016016:Proportional Hazards Models; D006435:Renal Dialysis / Q000009:adverse effects*; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000401:mortality* / Q000628:therapy*; D018570:Risk Assessment; D015996:Survival Rate
chemical_list: D010758:Phosphorus
keywords: Body composition; Hemodialysis; Hypophosphatemia; Mortality; Nutrition; Phosphorus