Trends, Determinants, and Impact on Survival of Post-Lung Transplant Weight Changes: A Single-center Longitudinal Retrospective Study

Abstract

Original Clinical Science-General Background. Weight gain is commonly seen in lung transplant (LTx) recipients. Although previous studies have focused on weight changes at fixed time periods and relatively early after transplant, trends over time and long-term weight evolution have not been described in this population. The study objectives were to document weight changes up to 15 years post-LTx and assess the predictors of post-LTx weight changes and their associations with mortality. Methods. Retrospective cohort study of LTx recipients between January 1, 2000, and November 30, 2016 (n = 502). Absolute weight changes from transplant were calculated at fixed time periods (6 mo, 1, 2, 5, 10, and 15 y), and continuous trends over time were generated. Predictors of weight changes and their association with mortality were assessed using linear and Cox regression analysis. Results. LTx recipients experienced a gradual increase in weight, resulting from the combination of multiple weight trajectories. Interstitial lung disease diagnosis negatively predicted post-LTx weight changes at all time points, whereas transplant body mass index categories were significant predictors at earlier time points. Patients with a weight gain of >10% at 5 years had a better survival (hazard ratio [HR], 0.36; 95% confidence interval [CI], 0.20-0.66), whereas a 10% weight loss at earlier time points was associated with worse survival (1 y: HR, 2.04; 95% CI, 1.22-3.41 and 2 y: HR, 2.37; 95% CI, 1.22-4.58). Conclusions. Post-LTx weight changes display various trajectories, are predicted to some extent by individual and LTx-related factors, and have a negative or positive impact on survival depending on the time post-LTx. These results may lead to a better individualization of weight management after transplant.

New-onset Obesity After Lung Transplantation: Incidence, Risk Factors, and Clinical Outcomes

“…Previously, we found that overweight LTx recipients lost weight in the early posttransplant period but regained weight between 1 and 2 y. 1 Although the magnitude of weight gain was below that of underweight and similar to normal-weight patients, it is probably enough to shift overweight patients into the obese category. The finding that COPD patients are at a higher risk of new-onset obesity raises questions regarding metabolic changes after transplantation.…”

“…New-onset obesity has been studied in other solidorgan transplants [14][15][16] but not extensively in the context of LTx. Previous studies showed that the prevalence of obesity increased from approximately 5% at transplant to 7% to 16% in the first 3 y after LTx 1,17,18 ; however, studies have not always clearly stated whether obesity was present before transplantation. We found that 13% of candidates had a BMI in the obese category, with 57% maintaining this status after transplantation.…”

“…1 In 41% of these cases, weight gain led to an upward shift in body mass index (BMI), placing approximately one third of individuals in the obese BMI range. 1 Consistent obesity throughout the pre-and post-LTx periods was found to be associated with poor survival and worse clinical outcomes, including longer mechanical ventilation duration and intensive care unit stay and higher rates of surgical complications, primary graft dysfunction, and new-onset diabetes after transplantation. [2][3][4][5][6][7] Yet, the impact of obesity developing post-LTx (new-onset) on morbidity and mortality remains ill defined.…”

Can we HALT obesity following lung transplant? A Dietitian‐ and Physiotherapy‐directed pilot intervention

“…The prevention of weight gain, overweight and obesity reduces the risk of CVD, diabetes and mortality among the general population 15,16 . Jomphe et al., 17 reported a lower median survival among LTx recipients with an unfavourable BMI evolution 2‐years post‐transplant, including those who became overweight or obese.…”