Suboptimal Sleep Patterns Raise Death Risk

New findings link changing or irregular sleep durations over time to increased risk of early mortality, especially in underserved communities.

Topline

A large U.S. cohort study found that adults with unstable or consistently suboptimal sleep durations had up to a 29% higher risk of all-cause mortality, with notable impacts seen across socioeconomic and racial groups.

Study Details

The study, led by Dr. Kelsie M. Full of Vanderbilt University Medical Center, analyzed the long-term sleep patterns of 46,928 low-income U.S. adults over five years. It aimed to assess how changes in sleep duration—whether short, healthy, or long—related to all-cause and cardiovascular mortality. Participants were primarily Black adults from 12 southeastern states, recruited through community health centers as part of the Southern Community Cohort Study (SCCS).

Methodology

Participants (mean age: 53 years; 65.4% women; 63.3% Black) self-reported their nightly sleep duration at two time points—enrollment and a follow-up 5 years later. Sleep was classified into three categories:

• Short: <7 hours

• Healthy: 7–9 hours

• Long: >9 hours

Nine sleep “trajectories” were defined based on how individuals’ sleep changed over time. These trajectories were then linked to mortality data obtained through the National Death Index up to December 2022.

Key Findings

• Over 65% of participants had suboptimal sleep trajectories.

• The highest mortality risk was found in those who transitioned from short to long sleep (HR 1.29), or who maintained long sleep durations (HR 1.27).

• Shifts from long to short sleep also carried elevated risk (HR 1.19).

• Cardiovascular death risk was similarly elevated in individuals with unstable sleep patterns.

• These associations were stronger in White participants and those with household incomes above $15,000, despite a higher prevalence of poor sleep in low-income Black participants.

Implications for Practice

For Individuals:
Maintaining a consistent and healthy sleep duration (7–9 hours) over time may reduce the risk of early death. Fluctuating sleep habits, especially drifting into very short or long sleep durations, could signal broader health concerns or lead to cardiovascular strain.

For Healthcare Providers:
Sleep duration should be assessed as a dynamic, modifiable health behavior during routine visits, particularly in underserved populations.
Providers are encouraged to integrate long-term sleep behavior screening into care plans, educate patients on sleep hygiene, and consider socioeconomic stressors affecting rest.

As noted in the accompanying editorial by Dr. Dayna A. Johnson of Emory University, sleep represents a “biological state and a modifiable behavior,” making it a crucial target for reducing health disparities and improving long-term outcomes.