The goal of this at-home, remote study is to understand the relationship between blood sugars and sleep in adults living with Cystic Fibrosis Related Diabetes (CFRD).

The study is a 10-day home-based, observational study of 30 adults with CFRD aimed at concurrently phenotyping glucose, sleep, and circadian rhythms. The remote study is designed to reduce participant burden while allowing for safe and robust objective data and specimen collection and to inform future clinical trial design. The objective of the proposed pilot and feasibility clinical study is to assess the feasibility of remotely phenotyping glycemia, sleep, and circadian rhythms of adults living with CFRD and to generate preliminary data to power a future clinical trial.

Inclusion Criteria:

Adult men or non-pregnant women volunteers (age 18-79) Able and willing to give consent and comply with procedures Known diagnosis of CF Related Diabetes (CFRD) and clinically stable with no significant changes in therapies within the prior 3 months

Concomitant Medications:

A. No initiation of an investigational drug within prior 28 days B. No initiation of new chronic therapy (e.g., ibuprofen, azithromycin, inhaled tobramycin, Cayston®) within prior 28 days C. No acute use of antibiotics (oral, inhaled or IV) or acute use of systemic corticosteroids for respiratory tract symptoms within prior 14 days D. No starting/stopping modulator therapy in the prior 3 months

Exclusion Criteria:

Blind, deaf, or unable to speak English Pregnant, nursing, or plan on pregnancy Current use of melatonin and unwilling to stop during the study With skin condition that precludes wearing sensors Within the last 4 weeks, acute CF exacerbation requiring IV antibiotics or hospitalization Major changes in diet or physical activity level in the last 4 weeks Untreated sleep and circadian disorders

Cystic fibrosis-related diabetes patients living in the US and identified from various sources: Rally website, the MGH Adult CF Program, the CF Foundation EnVision program, and the Oley Foundation.

We do not plan to share Individual Participant Data (IPD) with other researchers as the information collected, which includes detailed glucose profiles, sleep patterns, and circadian rhythm data from individuals with CFRD, is classified as protected health information.