Effects of nutritional status and dietetic interventions on survival in Cystic Fibrosis patients before and after lung transplantation

Abstract

Background: This study retrospectively investigated nutritional status, dietetic intervention and intake in Cystic Fibrosis (CF) patients before and after lung transplantation (LTX).

Methods: Body Mass Index (BMI), Fat Free Mass Index (FFMI) and nutritional intake were retrieved from 75 out-patients aged 15-53 years. Patients were seen every 3-4 months during the waiting list time (range 0-81 months) and up to 116 months after LTX. Survival was measured in months.

Results: The median BMI at baseline was 19.2 kg/m(2) (range: 15.3 to 28.4 kg/m(2)) with 29 patients (39%) below ≤18.5 kg/m(2). FFMI (measured in 65 patients) had a median of 15.2 kg/m(2) (range: 11.1 to 22.4 kg/m(2)) with 39 patients (60%) ≤16.7 kg/m(2) (men) or ≤14.6 kg/m(2) (women). Median energy intake was 2800 kcal, 239 kcal higher than the estimated energy requirement. However, 8 patients consumed ≥500 kcal less than recommended. Protein intake was 104 (range 60-187) g or 1.9 g/kg per day. Despite dietetic intervention with oral nutritional supplements (ONS) (36 patients), tube feeding (12 patients), or both (13 patients), BMI and FFMI hardly improved pre-LTX. LTX was performed in 51 patients (68%); 10 patients died during follow-up, median survival time was 41 months. A BMI ≤18.5 kg/m(2) was more prevalent in patients who died before LTX (6/9) or who died after LTX (4/10) than in patients who were still alive on the waiting list (5/15) or who survived LTX (14/41). Results for FFMI were comparable. From 6-12 months post-LTX, BMI and FFMI markedly improved, especially in underweight patients.

Conclusion: A BMI ≤18.5 kg/m(2) and an FFMI ≤16.7 kg/m(2) (men) or ≤14.6 kg/m(2) (women) appears to impair survival in LTX candidates with CF. Patients maintained a low body weight before LTX. After LTX weight gain is achieved.

Keywords: Body Mass Index; Cystic Fibrosis; Fat Free Mass; Lung transplantation; Nutritional intervention; Nutritional status.