Study Links Objectively Measured Nap Patterns to Mortality Risk in Older Adults

A new study analyzing long-term data from over 1,300 older adults has found associations between certain daytime napping habits and higher mortality rates. The research, published in JAMA Network Open, was conducted by teams from Mass General Brigham and Rush University Medical Center.

"It is important to note that this is correlation not causation. Excessive napping is likely indicating underlying disease, chronic conditions, sleep disturbances, or circadian dysregulation." — Chenlu Gao, Lead Author

Methodology: Tracking Rest with Wearables

The data was drawn from the Rush Memory and Aging Project, a long-running cohort study begun in 1997 focusing on cognition in older adults.

• Starting in 2005, participants wore wrist activity monitors for 10-day periods to collect objective rest-activity data.
• Researchers extracted detailed sleep patterns from this data, tracking nap length, frequency, time of day, and day-to-day variability.
• Participants were then followed for up to 19 years to track mortality outcomes.

Key Findings: Nap Duration, Frequency, and Timing

The analysis revealed several specific associations between nap patterns and mortality risk during the follow-up period.

Longer, more frequent, and morning naps were associated with higher mortality rates.

• Duration: Each additional hour of daytime napping per day was associated with an approximately 13% higher mortality risk.
• Frequency: Each extra nap per day was associated with an approximately 7% higher mortality risk.
• Timing: Morning nappers had a 30% higher mortality risk compared to those who napped in the afternoon.
• Regularity: Notably, irregular napping patterns were not associated with increased mortality risk.

Context and Significance

Daytime napping is common in older adulthood, with between 20% and 60% of older adults taking naps. While previous research has linked excessive napping to various health issues, many of those studies relied on potentially less accurate self-reported data.

Lead author Chenlu Gao stated this study is among the first to show an association between objectively measured nap patterns and mortality. The use of wearable activity monitors provides a more precise dataset for analysis.

"Now that we know there is a strong correlation between napping patterns and mortality rates, we can make the case to implement wearable daytime nap assessments to predict health conditions and prevent further decline." — Chenlu Gao

The researchers emphasize that their findings point to a correlation, not a direct cause. Napping patterns may serve as an important, easily measurable indicator of overall health and underlying conditions in the aging population.