Energy supplements rich in linoleic acid improve body weight and essential fatty acid status of cystic fibrosis patients.

BACKGROUND

Patients with cystic fibrosis who have steatorrhea frequently are underweight and have essential fatty acid (EFA) depletion, which is associated with a poor clinical course. It has been stated that poor EFA status is difficult to correct in patients with cystic fibrosis, and an impaired EFA metabolism with reduced synthesis of long-chain polyunsaturated fatty acids has been proposed. In this study, the effects of an oral energy supplement rich in linoleic acid were investigated in patients with cystic fibrosis who had a body weight below 95% of normal for height.

METHODS

Thirty-six patients (16 girls) more than 4 years of age were randomized either to a control group (n = 20, age 13.3 +/- 3.8 years, mean +/- SD) receiving intensive dietary counseling only, or an intervention group (n = 16, age, 10.4 +/- 4.3 years) treated for 3 months with dietary counseling plus 628 +/- 254 mL (= kcal) per day of an energy supplement rich in fat (31% of energy) and linoleic acid (16% of energy).

RESULTS

In contrast to the control group, the patients with supplemented diets achieved significant increases of energy intake (2189 +/- 731 kcal/day vs. 2733 +/- 762 kcal/day), weight for height (82.8% +/- 8.6% vs. 84.8% +/- 9.6% of normal), and body fat (5.1 +/- 1.7 kg vs. 5.8 +/- 2.2 kg) as well as the initially low values of plasma phospholipid linoleic acid (11.8% +/- 1.1% vs. 17.6% +/- 1.6% of total phospholipid fatty acids) and its main metabolite arachidonic acid (4.4% +/- 0.4% vs. 5.9% +/- 0.3%).

CONCLUSIONS

Patients with cystic fibrosis with low body weight and poor EFA status benefit from EFA-rich energy supplements and can synthesize arachidonic acid from the precursor linoleic acid.