Stunting is an independent predictor of mortality in patients with cystic fibrosis

BACKGROUND & AIMS: Some studies have shown a direct relationship between nutritional status and survival in Cystic Fibrosis (CF) patients. Body wasting, defined as a percentage of the ideal body weight for age, has been shown to be an independent predictor of mortality in CF. With respect to height only two studies were performed and these studies suggested that stunting is an important determinant of survival but both did not adjust statistical analysis for confounding variables. We aimed at determining the association between stunting and risk of mortality in CF patients. METHODS: 393 CF patients older than 6 years of age, 95 deceased, as cases, and 298 live, as controls, were enrolled in a nested case-control study. Stunting was defined by a height percentile < 5th. We performed a multivariate statistical analysis including height percentile and the following possible confounding variables: age, gender, Body Mass Index (BMI), Forced Expiratory Volume in 1 s (FEV1), genotype, pancreatic status, CF-related diabetes, colonization with Pseudomonas aeruginosa and/or Burkholderia cepacia. RESULTS: In the adjusted analyses stunting (OR 2.22 [IC 95%1.10-4.46]), wasting (OR 5.27 [IC 95% 2.66-10.41]), and FEV1 < 40% of predicted (OR 10.60 [IC 95% 5.43-20.67]) resulted the covariates that significantly predict the risk of mortality. CONCLUSIONS: Our study shows, for the first time, that stunting is a significant and independent risk factor for mortality in CF patients, and warrants an intervention of nutritional rehabilitation. Considering that nutritional interventions in stunted patients should be prolonged, are invasive and expensive, and might affect self-esteem and body image, their efficacy should be fully assessed by Randomised Controlled Trials