title: Metabolic syndrome and kidney disease: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Observational studies have reported an association between metabolic syndrome (MetS) and microalbuminuria or proteinuria and chronic kidney disease (CKD) with varying risk estimates. We aimed to systematically review the association between MetS, its components, and development of microalbuminuria or proteinuria and CKD. DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS AND POPULATION: We searched MEDLINE (1966 to October 2010), SCOPUS, and the Web of Science for prospective cohort confidence interval (CI) studies that reported the development of microalbuminuria or proteinuria and/or CKD in participants with MetS. Risk estimates for eGFR <60 ml/min per 1.73 m(2) were extracted from individual studies and pooled using a random effects model. The results for proteinuria outcomes were not pooled because of the small number of studies.
  
  
  RESULTS
  Eleven studies (n = 30,146) were included. MetS was significantly associated with the development of eGFR <60 ml/min per 1.73 m(2) (odds ratio, 1.55; 95% CI, 1.34, 1.80). The strength of this association seemed to increase as the number of components of MetS increased (trend P value = 0.02). In patients with MetS, the odds ratios (95% CI) for development of eGFR <60 ml/min per 1.73 m(2) for individual components of MetS were: elevated blood pressure 1.61 (1.29, 2.01), elevated triglycerides 1.27 (1.11, 1.46), low HDL cholesterol 1.23 (1.12, 1.36), abdominal obesity 1.19 (1.05, 1.34), and impaired fasting glucose 1.14 (1.03, 1.26). Three studies reported an increased risk for development of microalbuminuria or overt proteinuria with MetS.
  
  
  CONCLUSIONS
  MetS and its components are associated with the development of eGFR <60 ml/min per 1.73 m(2) and microalbuminuria or overt proteinuria.
authors.affiliation: Department of Nephrology and Hypertension, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
authors.forename: George
authors.initials: G
authors.lastname: Thomas
authors.forename: Ashwini R
authors.initials: AR
authors.lastname: Sehgal
authors.forename: Sangeeta R
authors.initials: SR
authors.lastname: Kashyap
authors.forename: Titte R
authors.initials: TR
authors.lastname: Srinivas
authors.forename: John P
authors.initials: JP
authors.lastname: Kirwan
authors.forename: Sankar D
authors.initials: SD
authors.lastname: Navaneethan
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000453:epidemiology; D016009:Chi-Square Distribution; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D011507:Proteinuria / Q000453:epidemiology; D018570:Risk Assessment; D012307:Risk Factors