Excess weight in patients with cystic fibrosis: is it always beneficial?

Introduction: The primary objective of this study was to find out the prevalence of overweight and obese status, as well as their association to pulmonary function, total cholesterol and vitamin D in patients with cystic fibrosis (CF). Materials and methods: This is a multicenter descriptive and cross-sectional study. Twelve Spanish hospitals participated. 451 patients with CF were included. Adults were classified according to body mass index (BMI) and children were classified according to BMI percentiles (WHO tables). Pearson's correlation, Anova, Student's t-test and multiple linear regression were conducted. Results: Mean age was 12.3 (range 4-57) years old, 51% were male and 18% had pancreatic sufficiency. Participants were classified in five nutritional status categories: 12% were malnourished; 57%, at nutritional risk; 24%, normally nourished; 6%, overweight; and 1%, obese. Pulmonary function in overweight or obese patients (91 +/- 19%) was better than in malnourished patients (77 +/- 24%) (p = 0.017). However, no difference was observed between those at nutritional risk (86 +/- 19%) or normally nourished (90 +/- 22%) groups. Overweight and obese patients had higher levels of total cholesterol (p = 0.0049), a greater proportion of hypercholesterolemia (p = 0.001), as well as lower levels of 25 OH vitamin D (p = 0.058). Conclusions: Prevalence of overweight and obese was 6 and 1%. Excess weight status does not offer any benefit in pulmonary function in comparison to normally nourished patients.