Discordant utility of ideal body weight and body mass index as predictors of mortality in lung transplant recipients.
BACKGROUND
An upper limit of 130% predicted ideal body weight (PIBW) has been promulgated for assessing lung transplant (LTx) candidacy, but no data in the lung transplant population support this value. A prior study used body mass index (BMI) to suggest greater mortality risk in obese allograft recipients, but the number of studied patients was small.


METHODS
Pre-operative PIBW percentage and BMI were obtained for all first-time, adult LTx recipients at our institution (n = 283). We compared survival data at 90 days and as of July 31, 2002, using multivariable regression and Cox modeling.


RESULTS
There were 46 obese (BMI > or = 30) patients and 72 patients >130% PIBW, including 43 patients previously thought to fall within a normal PIBW range who were reclassified as overweight for this analysis. Cox modeling revealed no significant impact of PIBW (>130% or continuous) or BMI (>30 kg/m(2) or continuous) on overall survival. Predicted ideal body weight also had no influence on 90-day mortality. When we tested PIBW in the group previously deemed of acceptable weight, we likewise found no association with mortality at 90 days or overall. For BMI only, 90-day odds ratios for death were significantly greater for obese (BMI > or = 30; odds ratio, 3.16; 95% confidence interval, 1.05-9.48) patients than for normal-weight patients.


CONCLUSIONS
Indices of pre-operative obesity did not predict long-term outcome in this large cohort of LTx recipients. The data suggest that BMI stratification may identify a group of patients at risk for increased short-term mortality, whereas PIBW is not a significant outcome predictor.
Culver
Daniel A
DA
Department of Pulmonary and Critical Care Medicine, Cleveland, OH 44195, USA. culverd@ccf.org
Mazzone
Peter J
PJ
Khandwala
Farah
F
Blazey
Holli C
HC
Decamp
Malcolm M
MM
Chapman
Jeffrey T
JT
D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008171:Lung Diseases / Q000401:mortality / Q000503:physiopathology / Q000601:surgery; D016040:Lung Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications; D018579:Patient Selection; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012737:Sex Factors; D013223:Statistics as Topic; D016019:Survival Analysis; D016896:Treatment Outcome