title: "Obesity paradox" in transcatheter aortic valve implantation.
abstract: BACKGROUND
  To determine whether body mass index (BMI) is associated with mortality in transcatheter aortic valve implantation (TAVI), we performed a mete-analysis of currently available studies.
  
  
  METHODS
  MEDLINE and EMBASE were searched through September 2015 using PubMed and OVID, to identify all studies investigating an association of BMI with early (in-hospital or 30-day) and mid-term (mean or median follow-up of approximately >6-month) mortality in patients undergoing TAVI.
  
  
  RESULTS
  Our search identified 11 eligible studies including 10,196 patients undergoing TAVI. A pooled analysis of 7 studies (enrolling 4046 patients) reporting a hazard ratio (HR) of BMI as continuous data for mid-term mortality demonstrated that greater BMI was associated with significantly less mid-term mortality (HR per 1-unit increase in BMI, 0.97; 95% confidence interval [CI], 0.94 to 1.00 [0.9982]: P = 0.04). Comparisons of overweight versus normal weight and obesity versus normal weight for mid-term mortality were not statistically significant. A pooled analysis of 3 studies (enrolling 3901 patients) reporting an odds ratio (OR) of BMI as continuous data for 30-day mortality demonstrated that greater BMI was associated with significantly less mortality (OR per 1-unit increase in BMI, 0.95; 95% CI, 0.92 to 0.98: P = 0.001). Comparisons of overweight versus normal weight (P = 0.02) and obesity versus normal weight (P = 0.04) for 30-day mortality were statistically significant.
  
  
  CONCLUSIONS
  BMI as continuous data may be associated with better early and mid-term post-TAVI survival. Whereas, overweight or obesity as categorized BMI may be associated with early, not mid-term, post-TAVI survival.
authors.affiliation: Department of Cardiovascular Surgery, Shizuoka Medical Center, Shizuoka, Japan - kfgth973@ybb.ne.jp.
authors.forename: Hisato
authors.initials: H
authors.lastname: Takagi
authors.affiliation: Department of Cardiovascular Surgery, Shizuoka Medical Center, Shizuoka, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Umemoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve; D015992:Body Mass Index; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods* / Q000401:mortality; D016009:Chi-Square Distribution; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000628:therapy*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods* / Q000401:mortality; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D009765:Obesity / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D016017:Odds Ratio; D065840:Protective Factors; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome