BMI as an Indicator of Serum Albumin and its Role as a Prognostic Factor for Taiwanese Patients with ESRD on Hemodialysis Anny Xiao, OMS II Yin-Cheng Chen, MD Athena Lin, MD Touro University College of Osteopathic Medicine Global Health Internship Program: Taiwan International Healthcare Training Center, Taipei, Taiwan
Background: Kidney Disease in Taiwan 2012 USRDS Annual Data Report
Background: Kidney Disease in Taiwan ESRD Prevalence: 2584 per million in 2010 Risk factors for CKD: Smoking, obesity, regular herbal medicine use, chronic lead exposure, hepatitis C, family history of ESRD Dialysis: 89.6% HD & 10.4% PD patients in 2010
Background: Kidney Disease in Taiwan Chinese herbal medicine use is independently associated with CKD in adults not using analgesics Consumption of Chinese herbs containing aristolochic acid shown to cause ESRD in Taiwan Aristolochic acid banned by Taiwan DOH in 2003 Herbal medicine perceived as less harmful than Western medicine
Background: BMI, Albumin, and ESRD BMI is predictive of mortality risk in ESRD patients Obesity paradox in hemodialysis patients: High BMI associated with lower all-cause mortality rates Indicator of nutritional status Hypoalbuminemia (< 3.5 g/dl) is an independent risk factor for morbidity and mortality Marker of inflammation and cardiac disease Possible explanations: Malnutrition and inflammation Protein-energy wasting
Background: BMI in Taiwanese population World Health Organization report: Asians have a higher percentage of body fat than Caucasians of the same age, sex, and BMI Chang et al. 2003 study conclusions: Taiwanese subjects had a relatively lower BMI but a higher BF% than Caucasians Proposed adjusted overweight and obesity criteria in the Taiwanese population: Overweight: BMI 23 kg/m 2 Obesity: BMI 25 kg/m 2
Study Goals Determine the relationship between BMI and serum albumin in a cohort of Taiwanese patients by cross-sectional analysis Further elucidate the role of BMI as a prognostic factor based on its relationship to albumin Suggest an optimal BMI range for ESRD patients on hemodialysis in Taiwan
Hypothesis A body mass index > 25 kg/m 2 correlates with a higher serum albumin than a body mass index < 25 kg/m 2 in Taiwanese ESRD patients on hemodialysis
Study Population Taiwanese ESRD patients receiving hemodialysis 3 times per week at the TIHTC Taipei Hospital Hemodialysis Center. N = 131 Average age: 63.0 ± 13.1 55% male, 45% female Average length of dialysis treatment: 4.67 years
Methods Data collected: Age Height and post-hd dry weight BMI was obtained by body weight (kg) divided by squared body height (m 2 ) Serum albumin Used as a marker for mortality risk Number of other systemic diseases Date of maintenance hemodialysis initiation
Methods Comparison of serum albumin in: Patients with BMI < 25 kg/m 2 (N = 81) versus patients with BMI > 25 kg/m 2 (N = 50) Matched for average age, number of comorbidities, years of hemodialysis treatment, and sex Subgroups according to current international BMI classification Underweight BMI < 18.5 kg/m 2 (N = 81) Normal BMI 18.5 24.9 kg/m 2 (N = 73) Overweight BMI 25 29.9 kg/m 2 (N = 44) Obese BMI > 30 kg/m 2 (N = 6)
Results Serum albumin in patients with BMI < 25 kg/m 2 Average: 3.37 ± 0.35 g/dl Median: 3.4 g/dl Serum albumin in patients with BMI > 25 kg/m 2 Average: 3.50 ± 0.32 g/dl Median: 3.5 g/dl Serum albumin is higher in patients with BMI > 25 kg/m 2 (P = 0.019)
Number of patients Results 50 47 45 40 35 30 34 32 25 20 18 serum albumin <3.5 g/dl serum albumin >3.5 g/dl 15 10 5 0 BMI <25 kg/m2 BMI >25 kg/m2
Average serum albumin (g/dl) Results Average serum albumin of BMI subgroups: 3.28 ± 0.44 g/dl for Underweight BMI < 18.5 kg/m 2 3.38 ± 0.34 g/dl for Normal BMI 18.5 24.9 kg/m 2 3.53 ± 0.32 g/dl for Overweight BMI 25 29.9 kg/m 2 3.30 ± 0.26 g/dl for Obese BMI > 30 kg/m 2 3.55 3.5 Overweight 3.45 3.4 3.35 Normal 18.2 21.9 27.0 31.8 Obese Underweight 3.3 3.25 16 18 20 22 24 26 28 30 32 Average BMI (kg/m 2 )
BMI (kg/m2 ) Results 3.53 ± 0.32 g/dl for overweight BMI 25-29.9 kg/m 2 Positive correlation of BMI and serum albumin R(42) = 0.4, p <0.05 30 29 28 27 26 25 24 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 4 4.2 Serum Albumin (g/dl)
Conclusions BMI in the overweight range (25.0 29.9 kg/m 2 ) was positively correlated with serum albumin levels Patients in the overweight BMI group had the highest average serum albumin levels BMI may be a useful prognostic factor in Taiwanese ESRD patients Taiwanese ESRD patients on hemodialysis may benefit from achieving a goal BMI of 25.0 29.9 kg/m 2
Implications Body weight management and optimizing dietary nutrient intake may help reduce high mortality rates in the Taiwanese hemodialysis population Expansion of Taiwan s nationwide CKD Preventive Project to include dietary counseling for ESRD patients on dialysis may improve prognosis Hemodialysis patients with BMI <25 kg/m 2 can be encouraged to eat more to replenish protein, energy and nutrients 多吃!
Acknowledgements Touro University California, College of Osteopathic Medicine Global Health Program Research Department Taiwan International Healthcare Training Center, Taipei Hospital, Taipei, Taiwan (ROC) Director Yin-Cheng Chen, MD, Taipei Hospital, Department of Nephrology Athena Lin, PhD, Touro University California, College of Osteopathic Medicine, Department of Basic Sciences
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