Increased donor BMI confers survival benefit in lung transplant recipients
Donor BMI appears to influence 1-year survival in lung transplant recipients, researchers reported at the virtual CHEST Annual Meeting.
“Several studies have demonstrated that recipients who are underweight or obese were associated with increased mortality after lung transplantation,” Sung H. Choi, MD, resident physician at Rutgers New Jersey Medical School, said during a poster presentation. “However, to our knowledge, there’s no study on the effect of donor BMI on its outcome.”
Researchers assessed 15,982 patients in the UNOS Standard Transplant and Analysis database who received a single or double lung transplant from 2005 to 2018. The median age was 59 years and 40% were women.
Donor BMI was categorized as underweight (< 18.49 kg/m2), normal weight (18.5-24.99 kg/m2), overweight (25-29.99 kg/m2) or obese (obesity class 1, 30-34.99 kg/m2; obesity class 2-3, > 35 kg/m2).
The average donor BMI was 25.9 kg/m2. Forty-five percent of donors were classified as normal weight.
Researchers reported an improved survival benefit at 1 year among patients who received a lung transplant from donors in obesity class 1 (HR = 0.867; 95% CI, 0.772-0.975) and obesity class 2-3 (HR = 0.804; 95% CI, 0.688-0.941) compared with those of normal weight, according to the abstract.
In adjusted analyses, the researchers reported lower odds of survival with increased donor age, male sex and presence of diabetes.
“Increased donor BMI appears to confer 1-year survival benefit for lung transplant recipients. A 15% and 20% reduction in mortality were respectively seen among recipients who received a lung transplant from class 1 and class 2-3 obese donors,” Choi said during the presentation. “While BMI is an imperfect measurement of obesity, underlying mechanisms such as chronic adaptations to hypoxic conditions in obese populations may explain an increase in survival and impact donor lung selection.”
The researchers concluded that further research is needed to validate and understand the relationship between donor BMI and survival in lung transplant recipients.