Impact of nutritional state on lung transplant outcomes

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.

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.

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.

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.