Effect of Lubiprostone on Nutritional Status and Pulmonary Function in Adults With Cystic Fibrosis
Effect of Lubiprostone on Nutritional Status and Pulmonary Function in Adults With Cystic Fibrosis
Cystic fibrosis (CF) results in thickened secretions in multiple organ systems including the
 lungs and gastrointestinal (GI) tract. Patients commonly suffer from nutritional deficiency,
 and achieving and maintaining adequate nutrition is an important goal of therapy because it
 is positively correlated with lung function. Lubiprostone activates chloride channels in the
 GI tract. Because its mechanism of action closely parallels the disease pathology,
 lubiprostone has the potential to provide GI benefits beyond the relief of constipation. This
 project is an observational study to examine the effects of lubiprostone on nutritional
 status and lung function in adults with CF. Our hypothesis is that lubiprostone will have
 beneficial effects on nutritional status.
Background: Cystic fibrosis (CF) affects an estimated 30,000 people in the United States. It
 is caused by a mutation in the gene encoding a protein called cystic fibrosis transmembrane
 regulator (CFTR). This protein functions as a chloride channel in epithelial cells of
 multiple organ systems. The mutation results in a dysfunctional or absent CFTR channel and a
 decrease in chloride secretion, which results in thickened secretions in multiple organ
 systems including the lungs and gastrointestinal (GI) tract. This patient population commonly
 suffers from nutritional deficiency, and achieving and maintaining normal nutritional status
 is an important goal of therapy as body mass index (BMI) is positively correlated with forced
 expiratory volume in 1 second (FEV1), a measure of pulmonary function. Lubiprostone activates
 type 2 chloride channels (ClC-2) on the apical membrane of GI epithelial cells. Because its
 mechanism of action closely parallels the disease pathology, lubiprostone has the potential
 to provide GI benefits beyond the relief of constipation. Objectives: The proposed pilot
 project is a prospective observational study to examine the effects of lubiprostone in adults
 with CF. The specific aims are to determine the effects of lubiprostone on: 1) nutritional
 markers and 2) pulmonary function in adults with CF. Methods: Adults with CF who are
 currently taking lubiprostone chronically will be sought for enrollment. Study subjects will
 be followed for approximately 3-months with serial assessment of indicators of nutrition and
 pulmonary function. Nutritional markers to be measured include body weight, albumin,
 prealbumin, and vitamins A, D, and E. Pulmonary function will be assessed by pulmonary
 function tests, a survey to monitor for symptoms of pulmonary exacerbation, and monitoring of
 the frequency of hospitalizations and IV antibiotic use. Expected Results: We expect to see a
 beneficial effect on nutritional markers, body weight, and BMI. We hope this translates into
 a concomitant improvement in pulmonary function.
Inclusion Criteria:

 -  Planning or currently on chronic lubiprostone therapy (chronic is defined as at least
 one 24 microgram capsule by mouth every other day

 -  Body mass index (BMI) of less than 22 for females and less than 23 for males at the
 initiation of chronic lubiprostone therapy

 -  Initiation of chronic lubiprostone therapy within 1 month of enrollment

 -  Age over 18

 -  Currently taking a multivitamin

 Exclusion Criteria:

 -  History of noncompliance with medications and other CF therapies

 -  History of hospital admissions for CF exacerbations of ≥2 in the last 6 months

 -  FEV1 les than 40% of expected (severe dysfunction) at most recent assessment in the
 ambulatory setting

 -  Currently registered on a lung transplant waiting list

 -  Any other condition, in the opinion of the investigators, that interferes with the
 ability of the study subject to comply with study requirements, confers significant
 risk, or limits the ability of the subject to complete the study