Role of Body Fat Distribution in Metabolic and Pulmonary Decline in Cystic Fibrosis (ORBIT-CF)

Inclusion Criteria

CF inclusion criteria

• confirmed CF diagnosis based on sweat testing by pilocarpine iontophoresis and/or CFTR genotyping with two disease causing mutations
• be aged ≥ 16 yrs
• clinically stable, defined as no changes in medical regimen (including medications) for at least 21 days prior to study visit
• participation in the CFF Patient Registry

Longitudinal study inclusion

CF participants who have normal glucose tolerance results after their initial study oral glucose tolerance test (OGTT).

Healthy controls inclusion criteria

• male or female ages 16 years and older
• clinically stable. Healthy controls will be recruited who are similar in age, gender, and BMI as the participants with CF.

Exclusion Criteria

CF exclusion criteria

• diagnosis of CF-related diabetes (CFRD)
• nocturnal tube feeds
• life expectancy \<6 months
• history of or on waiting list for lung transplant
• un-removable metal that is incompatible with MRI
• inability or unwillingness to perform major study activities (OGTT, DEXA, MRI) due to claustrophobia, fear of blood draw, or other reasons
• current pregnancy or lactation
• study visit falls between window of 1 week to 8 weeks of initiation of CFTR modulator
• use of chronic oral corticosteroids,
• in the opinion of the CF Care Team or study physician, participant should not participate in the study, or
• inability to provide informed consent or assent.

Healthy controls exclusion criteria

• malignant neoplasm (other than localized basal cell cancer of the skin) during the previous 5 years
• respiratory (including asthma), endocrine (including diabetes), autoimmune, or other chronic disease
• HIV or other chronic infection
• current use of any medications to treat an acute or chronic disease or illness (anti-depressants, anti-anxiety medications are acceptable),
• acute illness within the past 3 weeks
• intravenous or oral antibiotics or use of systemic corticosteroids within the past 3 weeks
• inability or unwillingness to perform major study activities due to claustrophobia, fear of blood draw, or other reasons
• current pregnancy or lactation, or
• inability to provide informed consent or assent.