With better medical care, patients with cystic fibrosis (CF), a life-threatening disease, are enjoying longer lives. As the CF life expectancy increases, conditions such as CF-related diabetes (CFRD) become more prevalent. Nutrition plays a major role in maintaining optimal health in cystic fibrosis (CF). This project is designed to investigate nutrition-related factors, such as diet and body composition, on outcomes in patients with CF. The data generated from this study will be used to inform future nutrition intervention studies in adults with CF and CFRD.

Research methods include blood draws for plasma markers of oxidative stress and metabolomics (the measurement of thousands of small chemicals in the blood), magnetic resonance imaging (MRI, to assess energy capacity and thigh fat), dual energy X-ray absorptiometry (DEXA, to assess total and regional body fat and muscle), and indirect calorimetry (to assess resting energy expenditure and whole body fat oxidation). Clinically-relevant data, such as lung function, CF genotype, and diabetes status will be obtained from the electronic medical record and the CF Registry.

Cystic Fibrosis

Inclusion Criteria:

• have confirmed CF diagnosis with at least one Class I to III CFTR mutations
• age ≥ 18 yrs
• on a clinically-stable medical regimen for 3 wks
• no intravenous or oral antibiotics for at least 3 wks prior to study visit

Exclusion Criteria:

• current pregnancy
• unwilling or unable to discontinue enteral tube feeds for one night before the study visit, if applicable
• most recent FEV1% <40%
• drug (recreational or prescription) or alcohol abuse
• pacemaker or any electronic implantable device
• unable to give informed consent

Healthy volunteers

Inclusion criteria:

• 18-50 yrs of age
• ambulatory status
• absence of hospitalization in the previous year except for accidents

Exclusion criteria:

• current pregnancy
• current active malignant neoplasm or history of malignancy (other than localized basal cell cancer of the skin) during the previous 5 years
• current respiratory disease including asthma, chronic obstructive pulmonary disorder, or emphysema
• current chronic autoimmune or pro-inflammatory disease
• history of tuberculosis, HIV, or other chronic infection
• previous diagnosis of type 1 or type 2 diabetes with active treatment with insulin or other glucose lowering medication
• advanced (≥ stage 3) renal disease
• body mass index (BMI) ≥ 30 kg/m2
• acute illness (such as a viral infection) within the past 2 weeks
• current use of any prescription medications that would indicate presence of an acute or chronic medical condition that may influence study results
• drug (recreational or prescription) or alcohol abuse
• weight instability (± 10% body weight within the last 6 months) or current participation in weight loss or weight gain program
• inability to provide informed consent.

Adults with cystic fibrosis and healthy volunteers from the Atlanta community