The Obesity Paradox and Mortality Associated With Surrogates of Body Size and Muscle Mass in Patients Receiving Hemodialysis

• Published in: Mayo Clinic proceedings Vol. 85; no. 11; pp. 991 - 1001
• Main Authors: Kalantar-Zadeh, Kamyar, MD, MPH, PhD, Streja, Elani, MPH, Kovesdy, Csaba P., MD, Oreopoulos, Antigone, PhD, Noori, Nazanin, MD, PhD, Jing, Jennie, MS, Nissenson, Allen R., MD, Krishnan, Mahesh, MD, Kopple, Joel D., MD, Mehrotra, Rajnish, MD, Anker, Stefan D., MD, PhD
• Format: Journal Article
• Language: English
• Published: Rochester, MN Elsevier Inc 01.11.2010; Mayo Foundation; Elsevier, Inc; Elsevier Limited; Mayo Foundation for Medical Education and Research
• Subjects: Biological and medical sciences; Body Mass Index; Cohort Studies; Complications and side effects; Creatine - blood; Epidemiology; Female; General aspects; Health aspects; Hemodialysis patients; Humans; Internal Medicine; Kidney Failure, Chronic - blood; Kidney Failure, Chronic - mortality; Kidney Failure, Chronic - therapy; Male; Medical sciences; Metabolic diseases; Middle Aged; Muscle, Skeletal - anatomy & histology; Muscle, Skeletal - chemistry; Muscle, Skeletal - physiology; Obesity; Obesity - blood; Obesity - mortality; Original; Proportional Hazards Models; Public health. Hygiene; Public health. Hygiene-occupational medicine; Renal Dialysis; Survival Analysis; Time Factors; Weight Gain; United States; lean body mass; chronic kidney disease; PEW; urea kinetic modeling; dialysis dose; body mass index; dual-energy X-ray absorptiometry; Kt/V; DEXA; LBM; UKM; hemodialysis; HD; CKD; protein-energy wasting; BMI; Human; Obesity; Hemodialysis; Mortality; Nutrition disorder; Patient; Corporal biometry; Epidemiology; Mass; Medicine; Extrarenal dialysis; Association; Body size; Muscle; Nutritional status
• ISSN: 0025-6196; 1942-5546
• DOI: 10.4065/mcp.2010.0336

OBJECTIVE To determine whether dry weight gain accompanied by an increase in muscle mass is associated with a survival benefit in patients receiving maintenance hemodialysis (HD). PATIENTS AND METHODS In a nationally representative 5-year cohort of 121,762 patients receiving HD 3 times weekly from July 1, 2001, through June 30, 2006, we examined whether body mass index (BMI) (calculated using 3-month averaged post-HD dry weight) and 3-month averaged serum creatinine levels (a likely surrogate of muscle mass) and their changes over time were predictive of mortality risk. RESULTS In the cohort, higher BMI (up to 45) and higher serum creatinine concentration were incrementally and independently associated with greater survival, even after extensive multivariate adjustment for available surrogates of nutritional status and inflammation. Dry weight loss or gain over time exhibited a graded association with higher rates of mortality or survival, respectively, as did changes in serum creatinine level over time. Among the 50,831 patients who survived the first 6 months and who had available data for changes in weight and creatinine level, those who lost weight but had an increased serum creatinine level had a greater survival rate than those who gained weight but had a decreased creatinine level. These associations appeared consistent across different demographic groups of patients receiving HD. CONCLUSION In patients receiving long-term HD, larger body size with more muscle mass appears associated with a higher survival rate. A discordant muscle gain with weight loss over time may confer more survival benefit than weight gain while losing muscle. Controlled trials of muscle-gaining interventions in patients receiving HD are warranted.