“More to It Than Meets the BMI”

This blog post title is quoted from a clever editorial which reviews the use of BMI and the effect of obesity with outcomes after liver transplantation (Liver Transpl 2014; 20: 253-54, related article pages 281-90.)

Key points from editorial and study:

  • Study enrolled 202 consecutive adult (mean 51 years) patients (200-2010) as part of cohort study.  Data was obtained at time of transplantation and reviewed with retrospective analysis. NAFLD was transplant indication in 7%.
  • “Use of BMI as a marker of obesity is flawed.” Authors showed only 86% agreement between calculated BMI and percent body fat as measured with DXA.
  • Patients with high BMI due to greater lean muscle mass may have improved outcomes.  Sarcopenia (loss of muscle mass) likely has greater effect on outcomes.
  • The study shows that the combination of diabetes and obesity increases the risk of complications and prolongs hospital stays (5.81 days, P<0.01).
  • Metabolic risk factors had no effect on 30-day, 1-year, or 5-year patient survival.

Another article in same issue: Liver Transpl 2014; 20: 311-22. This study retrospectively examined 148 normal-weight, 148 overweight, and 74 obese patients who underwent living donor liver transplantation. Key finding: “there were no differences in graft survival [hazard ratio (HR) =0.955] or recipient survival [HR = 0.90]” between these groups.  Obese patients do require larger grafts which can delay identifying suitable donor.

Bottomline from editorial: “this study shows us that the combination of diabetes and obesity dramatically increases the risk of complications” but not survival.  “If there comes a day when the cost of a human life is less than the cost of a 6- to 7-day hospital stay, that is the day to reckon. None of us may survive.”

Related blog post:

Sarcopenia, fatigue, and nutrition in chronic liver … – gutsandgrowth