Relation between fatty acid composition and clinical status or genotype in cystic fibrosis patients

To evaluate the relation of clinical parameters and genotype with the serum phospholipid fatty acid (FA) composition in cystic fibrosis (CF) patients.

A blood sample was taken from CF patients with stable pulmonary disease for the determination of phospholipid FA composition and vitamin E concentration who had been followed for at least 6 months at our Cystic Fibrosis Centre. Genotype, age, pancreatic function, nutritional status, caloric intake, pulmonary function and presence of Pseudomonas colonization, liver disease or diabetes mellitus were recorded. Patients were divided into two groups according to their genotype (group A: mutation class I, II, or III, group B: mutation class IV, V).

CF patients (group A and B together) have significantly lower docosahexaenoic acid (DHA) (p < 0.007) and linoleic acid (LA) (p < 0.0001) and higher dihomogammalinolenic acid (DHGLA) (p < 0.0001), oleic acid (OA) (p < 0.0001) and Mead acid (MA) (p < 0.0001), resulting in an increased ratio of arachidonic acid (AA)/DHA (p < 0.004), MA/AA (p < 0.0001) and OA/LA (p < 0.0001). Compared to group B, group A had a lower LA (p < 0.002) and a higher DHGLA (p < 0.002), 22:4omega-6 (p < 0.03), 22:5omega-6 (p < 0.03) and 20:3omega-9 (p < 0.04). There was however no significant difference between the groups for age, pulmonary function, nutritional status and vitamin E concentration. There was no relation of serum FA composition with nutritional status, caloric intake, pancreatic function, gender, pulmonary function, Pseudomonas colonization or diabetes mellitus. In CF with liver disease the DHA was lower than in the patients of the same genotype.

FA disturbances are more pronounced in the severe CF genotypes and the presence of CF-related liver disease. Future studies on supplementation should take these parameters into account.