A study shows that stable, moderate sleep patterns are linked to better health in older adults, while inconsistent or short sleep patterns pose risks to physical, cognitive and social well-being.
Study: The association between sleep duration trajectories and successful aging: a population-based cohort study. Image credits: Shutterstock AI
A recent study published in the BMC Public Health magazine examined how different sleep duration patterns are associated with “successful aging” among older adults in China. The study highlighted that both sleep duration and sleep consistency are important factors in healthy aging outcomes. Their findings indicate that longer and shorter sleep patterns are associated with a lower likelihood of successful aging, highlighting the critical nature of monitoring sleep changes in older and middle-aged adults.
Background
The population of people over 60 worldwide is expected to rise from 12% in 2015 to 22% in 2050. China in particular has a rapidly increasing aging population, which is expected to reach 397 million and account for 28% of the population by 2040. Life expectancy (on average 77.6 years) is much greater than healthy life expectancy, which is only 68.4 years.
Successful aging is defined as living longer while maintaining cognitive and physical health, social engagement and mental well-being while remaining free from serious diseases. Less than 16% of older adults in China achieve this, compared to significantly higher figures in South Korea and Japan. Promoting successful aging in the Chinese population requires identifying modifiable risk factors.
Both excessive and insufficient sleep have been linked to adverse outcomes such as depression, cognitive decline and mortality. However, previous research has shown mixed results regarding the link between successful aging and sleep duration. One study in China found links between short sleep and a lower chance of successful aging, and another study in the United States suggested that long sleep could reduce the chances of aging. healthy aging.
Previous studies have not considered long-term changes in sleep duration over time, instead focusing on sleep duration measured at a single point. Persistent short sleep is associated with higher risks of mortality, dementia, heart disease and type 2 diabetes, but the relationship between sleep patterns over time and successful aging has not been studied.
About the study
In this study, researchers examined how different sleep duration patterns were associated with successful aging among older and middle-aged Chinese adults and how monitoring these patterns could inform public health strategies.
The study used data collected through longitudinal surveys conducted between 2011 and 2020, which were intended to be representative of adults over the age of 45 across China. The final analysis included 3,306 participants who were disease-free at baseline and over 60 in 2020.
Participants’ total sleep duration was calculated by combining nighttime sleep and daytime naps using self-reported sleep habits data. Sleep patterns reported in 2011, 2013 and 2015 were analyzed to determine the trajectory of sleep habits.
Researchers defined successful aging based on five criteria, including the absence of chronic diseases such as heart disease, cancer and diabetes; independent physical functioning for daily activities; cognitive functioning; minimal depression symptoms; and social well-being through participation in social activities such as community events or games.
The analysis used a latent class mixed model to classify participants’ sleep duration trajectories into different patterns and used logistic regression models to estimate the probabilities of successful aging for different sleep trajectory groups. The analysis was adjusted for factors such as body mass index (BMI) and lifestyle factors including physical activity, drinking and smoking, income, education, place of residence, marital status, gender and age.
Findings
The average age of the 3,306 participants was 60 years, and almost half were women. In nine years, 81% had no serious chronic diseases, but only 13.8% met the criteria for successful aging.
Researchers identified five sleep patterns: short stable, increasing, decreasing, long stable and normal stable. The group with normal stable sleep patterns showed the highest successful aging rates, at 18.1%. Normal stable and long stable sleep patterns were more beneficial for successful aging, while short stable, increasing and decreasing sleep patterns were associated with a lower likelihood of successful aging. Notably, the decreasing sleep trajectory was not statistically significant, likely due to sample size.
It was also found that sleeping less than seven hours reduces the likelihood of successful aging, and participants with high variability in sleep duration also had lower odds of successful aging. These findings were consistent across groups, including weight classes, smoking and alcohol consumption, gender and age.
Conclusions
Researchers have shown that a consistent, normal, and stable sleep pattern is the most beneficial trajectory for successful aging. Chronic short sleep can increase stress hormones (such as cortisol) and increase inflammation, which can increase the risk of age-related diseases. Long-term sleep problems may be related to mental and cognitive decline, sarcopenia (muscle loss), and metabolic disorders. Gradual increases in sleep duration can indicate health problems such as sleep apnea or depression, which also affect successful aging.
Importantly, these findings support the concept that sleep consistency is as critical as duration for positive aging outcomes. They suggest that persistent sleep deprivation or gradually increasing sleep duration are barriers to successful aging, highlighting the importance of dynamic sleep monitoring as a preventive measure.