Impact of nutritional state on lung transplant outcomes

Abstract

Background: When high-risk lung transplant candidates are evaluated, nutritional state is often neglected. We evaluated the prevalence of markers reflecting pre-transplant malnutrition and their association with post-operative complications and death.

Methods: From January 2005 to July 2010, 453 patients underwent primary lung transplantation at our institution. Pre-operative nutrition-related variables, including body mass index and weight/height ratio, reflecting cachexia, and albumin, total protein, immunoglobulins, and absolute lymphocyte count were considered in identifying risk factors for time-related major post-operative complications (renal failure requiring dialysis, respiratory failure requiring tracheostomy), pulmonary or bloodstream infections, and death.

Results: Forty-eight patients had BMI <18.5 kg/m(2), 41 had a weight/height ratio ≤ 0.3, 102 had albumin <3.5 g/dl, 110 had total protein <6 g/dl, and 112 had an absolute lymphocyte count <1,000/μl, indicative of a malnourished state. At 6 months, 30% had experienced pulmonary infection, with lower total serum protein concentration an important risk (p = 0.02). One-year actuarial mortality was 15%; risk factors included lower serum albumin (p = 0.004), particularly when <3 g/dl. In contrast, variables reflecting nutritional state were not statistically significantly correlated with dialysis, respiratory failure requiring tracheostomy, or bloodstream infections.

Conclusion: Although malnutrition is uncommon in lung transplant patients, those at extremes of low serum albumin and total protein have worse survival and increased risk of post-operative infection. Strategies to improve nutrition of these high-risk candidates awaiting lung transplantation should be developed.