Objective sleep, a novel risk factor for alterations in kidney function: the CARDIA study.

Area of Science:

• Nephrology
• Sleep Medicine
• Epidemiology

Background:

• Objective sleep measurement is crucial for understanding its impact on chronic disease.
• The relationship between sleep parameters and kidney function decline, specifically estimated glomerular filtration rate (eGFR), requires further investigation.
• Previous studies have not fully elucidated the long-term associations between objectively measured sleep and eGFR changes.

Purpose of the Study:

• To investigate the association between objectively measured sleep parameters (duration, fragmentation, quality) and 10-year changes in eGFR.
• To determine if sleep characteristics predict longitudinal changes in kidney function.
• To explore these relationships in a community-based cohort free from cardiovascular and chronic kidney disease at baseline.

Main Methods:

• Utilized data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, including an ancillary sleep study.
• Employed wrist actigraphy for objective sleep duration and fragmentation assessment and the Pittsburgh Sleep Quality Index (PSQI) for subjective sleep quality.
• Employed generalized estimating equation regression and linear models to analyze the association between sleep parameters and eGFR changes over 10 years, controlling for relevant risk factors.

Main Results:

• No significant association was found between sleep parameters and the 5-year change in cystatin-C-estimated eGFR (eGFRCys).
• A significant association was observed between decreased sleep duration and increased eGFR (estimated from serum creatinine, eGFRCr): each 1-hour decrease in sleep was linked to a 1.5 mL/min/1.73 m² increase in eGFRCr over 10 years.
• Poorer sleep quality (higher PSQI score) was also significantly associated with higher eGFRCr: each one-point increase in PSQI score correlated with a 0.5 mL/min/1.73 m² increase in eGFRCr over 10 years.

Conclusions:

• Shorter sleep duration and poorer sleep quality are associated with higher kidney filtration rates over a 10-year period in a community-based sample.
• These findings suggest a potential link between impaired sleep and altered kidney function dynamics.
• Further research is warranted to understand the mechanisms underlying this association and its clinical implications for kidney health.