Nutritional rehabilitation in cystic fibrosis: controlled studies of effects on nutritional growth retardation, body protein turnover, and course of pulmonary disease

Supplemental nasogastric feeding in cystic fibrosis patients during treatment for acute exacerbation of chest disease

The use of overnight, nasogastric, nutritional supplementation during hospitalization of children with cystic fibrosis (CF) receiving antibiotic therapy for acute exacerbations of respiratory disease was evaluated in 11 children (mean age = 7.75 years). Supplementary feeding significantly increased inpatient energy intake from 116 +/- 30% to 165 +/- 30% (P less than 0.001) of recommended dietary allowance with minimal effect on oral intake. It also resulted in significantly improved weight gains but neither increased energy intakes nor weights were sustained at short-term (mean = 5.7 weeks) or long-term (mean = 21.6 weeks) follow-up. The notion that short bursts of nasogastric feeding for inpatients with CF improve growth status is not supported. However, the study did show that treatment of chest infections alone does not positively affect spontaneous oral energy intake.

Fat intake is low in cystic fibrosis despite unrestricted dietary practices

A prospective study of caloric intake and specific nutrient composition was performed in 64 cystic fibrosis patients aged 0.3 to 18 yr. Linear regressions and multiple stepwise regressions revealed no significant correlations between any individual dietary parameter and age, height, weight, percentile of weight or height, Shwachman Score, and pulmonary parameters. The caloric intake varied widely in individual patients and in different age groups. Despite unrestrictive dietary practices, the fat intake (33.7% +/- 8) was below that recommended for these linoleate deficient patients.

Bronchodilation from intravenous theophylline in patients with cystic fibrosis: results of a blinded placebo-controlled crossover clinical trial

Most patients with cystic fibrosis (CF) eventually develop chronic obstructive pulmonary disease and theoretically could benefit from theophylline therapy. The purpose of this study was to investigate the pharmacologic response to intravenous theophylline by pulmonary function tests (PFT) and the theophylline pharmacokinetics in patients with CF. A randomized, double-blind, placebo-controlled, crossover trial was conducted in 10 ambulant patients with CF (5 females, 5 males), aged 11 to 21 years. Each patient received an intravenous dose of theophylline and normal saline over 1/2 hour on consecutive days. Spirometry and whole-body plethysmography were performed at baseline, 1, 3, 5, and 7 h after the theophylline dose, and 10 blood samples were collected over 9 h on both study days. The percent change of PFT from the baseline was recorded. Analysis of variance for balanced two-period crossover design was used to evaluate the effectiveness of theophylline therapy. The serum concentration (Conc.) vs. time data were fitted using nonlinear least-squares regression analysis. The theophylline dose administered was 7.9 +/- 0.4 (mean +/- SD) mg/kg, which produced a maximal Conc. (Cmax) of 14.6 +/- 2.7 microgram/ml. The half-life (T1/2), volume of distribution (Vd), and total body clearance (TBC) were 4.9 +/- 1.9 h, 537 +/- 124 mL/kg, and 80 +/- 16 ml/h/kg, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased energy expenditure in young children with cystic fibrosis

To investigate the role of energy expenditure in the altered energy balance in cystic fibrosis (CF), total energy expenditure (TEE) was measured by the doubly-labelled water method in 9 clinically well CF infants (body weight 7.3-10.9 kg) without chronic lung disease. CF infants had 25% higher rates of energy expenditure when compared with data derived from measurements of TEE obtained by the same method in 16 healthy infants, matched for age and body weight. Mean TEE (SEM) for CF was 950 (38) kcal, vs 876 (72) kcal for controls matched for age and 758 (46) kcal for controls matched for weight. Although subclinical disease activity cannot be excluded as a determinant of the excess TEE, the possibility of an energy-requiring basic defect is suggested, because further analysis indicated that factors other than body weight, degree of underweight, presence of pancreatic insufficiency, or presence of lung disease were important. Increased TEE may contribute to undernutrition in CF, even in the absence of chronic lung disease.

The use of a synthetic prostaglandin E1 analogue (misoprostol) as an adjunct to pancreatic enzyme replacement in cystic fibrosis

Eleven cystic fibrosis children (mean age, 9.6 years) were chosen at random to participate in a study to observe the effects of concurrently stimulating gastric/duodenal bicarbonate secretion and inhibiting gastric acid secretion, using a methylated prostaglandin E1 analogue in patients with pancreatic insufficiency and taking pancreatic enzymes. Percentage fat absorption in 3-day stool collections were calculated before and after commencing therapy with misoprostol, 400 micrograms/day in divided doses. We found a significant reduction in fat output (14.7 +/- 11.7 versus 7.5 +/- 3.5 g/day, p less than 0.05) in the study group as a whole and a significant reduction in steatorrhoeic level as a percentage of fat intake in all of the patients with abnormal base-line collections (23.1% versus 9.2%, p less than 0.002). We conclude that misoprostol should be considered in cystic fibrosis patients with steatorrhoea as a means of improving nutrient absorption.

Diet for cystic fibrosis. Nutritional requirements and prescriptions

Diet plays no direct role in neutralizing the effects of the basic defect in cystic fibrosis, but it can prevent some of the acquired damage caused by complications. Adequate caloric intake provides the energy needed for exercise and cell metabolism, a strong diaphragm, normal cellular immunity, and a positive psychological outlook. Clinical management is aimed at achieving good nutrition. Patient education about nutrition and use of dietary supplements should be started immediately upon diagnosis. Careful clinical examinations and regular follow-up are necessary to detect complications that will interfere with good nutrition. Complications must be treated aggressively. Psychological and social stresses need to be recognized, and psychological referral may be necessary. The clinician's best tools to achieve these goals are the patient's dietary and gastrointestinal history, the anthropometric measurements taken at each office visit, regular patient assessment, and constant attention to detail in monitoring and charting the course of disease. Extraordinary measures, such as nighttime feedings by nasogastric or gastrostomy tube and intravenous hyperalimentation, may be necessary. For best results, these measures must be started before pulmonary complications threaten survival.

Energy expenditure of patients with cystic fibrosis

Resting energy expenditure was measured by open-circuit indirect calorimetry in 71 patients, aged 8.9 to 35.5 years, with cystic fibrosis who had no recent history of acute lung infection. Pulmonary function and nutritional status were studied simultaneously. In most patients, resting energy expenditure was above normal (range 95% to 153% of predicted values for age, sex, and weight as derived from the Harris Benedict equations), and was negatively correlated with pulmonary function (P less than 0.01) and nutritional status (P less than 0.01) when expressed as a percentage of body fat. Pulmonary status was positively correlated with nutritional status (P less than 0.01). We conclude that resting energy expenditure in patients with cystic fibrosis exceeds normal values and that the increase correlates with a deterioration in lung function and nutritional status.