Biological Aging Process May Be Impacted by These Sleep Traits

Inadequate and excessive durations of sleep are associated with an increased risk for accelerated biological aging, according to study findings published in the journal Sleep. 

It is well-documented that sleeping is important for the overall functioning of the body and that disturbances in sleep can impact the body’s physiology. Researchers conducted a study to assess the association between sleep traits and the risk for biological accelerated aging. 

The researchers used PhenoAge, which is a measure of biological age that can indicate if you are physiologically younger or older than your chronological age. Differences in chronological and physiologic age was defined as an acceleration (PhenoAgeAccel).

The study participants were given a questionnaire regarding the following sleep traits: sleep duration, chronotype, insomnia, and snoring. Participants reported the number of hours they typically spent sleeping and napping in a 24-hour period. Sleeping durations were reported as short (<6 hours), intermediate (6-8 hours), and long (≥9 hours).

Chronotype was assessed by asking the participants if they were a morning or evening person. Insomnia was determined by asking about difficulties initiating or maintaining sleep. Participants also reported if they were aware of snoring based on reports from individuals close to them.

A total of 336,559 participants from the UK Biobank cohort were included in this study. Some exclusion criteria were individuals who were non-White, used sleep medications, or had unavailable chronological age data. 

Of these participants, 157,227 (mean age, 58; 45.2% women) were considered biologically older individuals, with a PhenoAgeAccel score of greater than 0.

Compared to the control group, individuals in the biologically older cohort had significantly higher body mass index (BMI; mean, 28.59) and a higher prevalence of respiratory comorbidities (14.6%).

Biologically older individuals reported lower International Physical Activity Questionnaire (IPAQ) scores compared to the control population, which indicates less physical activity. 

A nonlinear, U-shaped relationship between sleep duration and PhenoAgeAccel risk was reported (P <.001), which shows that participants who sleep for an intermediate amount of time (6-8 hours) had the lowest risk.

A shorter sleep duration was associated with an estimated 7% higher PhenoAgeAccel risk (odds ratio [OR], 1.07; 95% CI, 1.03-1.11; P <.001), and long sleep duration was associated with an 18% increased risk (OR, 1.18; 95% CI, 1.15-1.22; P <.001). 

Compared to the morning chronotype, people with an evening chronotype had a positive correlation with PhenoAgeAccel risk (OR, 1.14; 95% CI, 1.10-1.18; P <.001). The morning chronotype had a protective effect on PhenoAgeAccel risk (OR, 0.87; 95% CI, 0.79-0.95).

There were no significant associations reported for participants with insomnia or snoring with PhenoAgeAccel risk.

“This study is distinguished by its large sample size, and relatively adequate sleep phenotypic and biochemical data for biological age calculation,” the researchers noted.

They concluded, “The study suggests that improving sleep can slow biological aging, highlighting the importance of optimizing sleep as an intervention to mitigate aging’s adverse effects.”

Study limitations included self-reporting sleep-related variables, an exclusive study population of White individuals, and selection bias as participants of the UK Biobank tend to be healthier and have higher levels of education.