Annals of Thoracic Medicine
ORIGINAL ARTICLE
Year
: 2015  |  Volume : 10  |  Issue : 3  |  Page : 169--175

Overweight-mortality paradox and impact of six-minute walk distance in lung transplantation


Kongkiat Chaikriangkrai1, Hye Yeon Jhun1, Edward A Graviss2, Soma Jyothula1 
1 Department of Medicine, Houston Methodist Hospital, Houston, United State
2 Department of Pathology and Genomic Medicine, Houston Methodist Research Institute, Houston, Texas, United State

Correspondence Address:
Kongkiat Chaikriangkrai
Houston Methodist Hospital 6550 Fannin St, Smith tower, suite1001, Houston, TX 77030
United State

Overweight-mortality paradox and impact of six-minute walk distance (SMWD) in lung transplantation Background: The objective of this study was to examine combined prognostic influence of body mass index (BMI) and SMWD on mortality in lung transplant recipients. Methods: Consecutive isolated lung transplant recipients were identified. Preoperative BMI and SMWD data were collected. The cohort was followed for all-cause mortality. Results: The study included 324 lung transplant recipients with mean age of 57 ± 13 years and 58% were male (27% obstructive, 3% vascular, 6% cystic fibrosis, and 64% with restrictive lung diseases). In the total cohort; 37% had normal BMI, 10% were underweight, 33% were overweight, and 20% were obese. The median SMWD was 700 feet. The lower SMWDgroup was defined as the patients who had SMWD <237 feet as determined by receiver operating characteristic (ROC). Based on this definition, 66 patients (20%) had lower SMWD. There were 71 deaths during a median follow-up of 2.3 years. In multivariate analysis, both BMI and SMWD were independently associated with death. Being overweight was associated with reduced mortality risk (hazard ratio (HR) 0.50, P = 0.042) compared to the normal BMI group, and this was primarily driven by early mortality posttransplant. This paradoxical overweight-mortality relationship remained significant in the lower SMWD group (HR 0.075, P = 0.018), but not in the higher SMWD group (P = 0.552). Conclusion: In lung transplant recipients under lung allocation score (LAS) era, pretransplant BMI and SMWD were independent predictors for mortality after the transplant. The lowest mortality risk was noted in a group of transplant recipients identified as overweight; whereas, being underweight or obese was associated with increased mortality.


How to cite this article:
Chaikriangkrai K, Jhun HY, Graviss EA, Jyothula S. Overweight-mortality paradox and impact of six-minute walk distance in lung transplantation.Ann Thorac Med 2015;10:169-175


How to cite this URL:
Chaikriangkrai K, Jhun HY, Graviss EA, Jyothula S. Overweight-mortality paradox and impact of six-minute walk distance in lung transplantation. Ann Thorac Med [serial online] 2015 [cited 2020 Sep 22 ];10:169-175
Available from: http://www.thoracicmedicine.org/article.asp?issn=1817-1737;year=2015;volume=10;issue=3;spage=169;epage=175;aulast=Chaikriangkrai;type=0