[Association between daytime napping and depressive symptoms in older women: The chain mediating role of frailty and C-reactive protein].
With the intensification of global population aging, the incidence of depressive symptoms among older women has increased year by year, affecting their quality of life and physical and mental health. Therefore, investigating the impact of daytime napping behavior on depressive symptoms in older women, particularly the regulatory effects of napping on frailty status and inflammatory response, is of important clinical and public health significance. This study aims to explore the relationship between daytime napping behavior and depressive symptoms in older women, with a focus on the chain mediating roles of frailty status and C-reactive protein (CRP) between napping and depressive symptoms.
This study used 5 waves of data from the China Health and Retirement Longitudinal Study (CHARLS), including 3755 female participants aged ≥45 years. First, descriptive statistics and difference analyses were used to summarize baseline characteristics of the participants. Second, Cox proportional hazards regression models were used to analyze the effects of napping habits and nap duration on depressive symptoms. To explore the biological mechanisms linking napping and depressive symptoms, path analysis was further conducted to examine the chain mediating roles of frailty status and CRP in the effect of napping on depressive symptoms. To control for potential confounding factors, all analyses were adjusted for multiple covariates, including age, education level, marital status, smoking, drinking, social participation, and physical exercise. Finally, subgroup analyses were conducted to further verify the moderating effects of different lifestyles on the impact of napping.
Napping behavior was significantly associated with a lower risk of depressive symptoms, particularly among women with nap durations of 5 to 30 minutes, who had the lowest risk of depressive symptoms. Specifically, individuals with nap durations of 5 to 30 minutes had a lower risk of depressive symptoms (HR=0.750, 95% CI 0.637 to 0.883, P<0.001), whereas those with naps longer than 60 minutes did not show a significant reduction in depressive symptom risk (HR=0.934, 95% CI 0.811 to 1.076, P=0.347). Further path analysis showed that there is a total indirect effect between napping and depressive symptoms (β=-0.0219, P<0.05), and there is an overall effect between the two (β=-0.081, P<0.05), indicating that napping could indirectly alleviate depressive symptoms by slowing frailty progression and reducing CRP levels. Subgroup analysis showed that the protective effect of napping on depressive symptoms was more pronounced among women who did not smoke or drink, exercised regularly, and participated in social activities, suggesting that the psychological protective effect of napping depends on an individual's overall health behavior pattern.
Daytime napping exerts a chain mediating effect on depressive symptoms in older women through frailty status and CRP levels. Moderate napping, especially short naps of 5 to 30 minutes, can effectively reduce the risk of depressive symptoms, and this effect may be achieved by improving physical function and alleviating frailty and inflammatory responses.
This study used 5 waves of data from the China Health and Retirement Longitudinal Study (CHARLS), including 3755 female participants aged ≥45 years. First, descriptive statistics and difference analyses were used to summarize baseline characteristics of the participants. Second, Cox proportional hazards regression models were used to analyze the effects of napping habits and nap duration on depressive symptoms. To explore the biological mechanisms linking napping and depressive symptoms, path analysis was further conducted to examine the chain mediating roles of frailty status and CRP in the effect of napping on depressive symptoms. To control for potential confounding factors, all analyses were adjusted for multiple covariates, including age, education level, marital status, smoking, drinking, social participation, and physical exercise. Finally, subgroup analyses were conducted to further verify the moderating effects of different lifestyles on the impact of napping.
Napping behavior was significantly associated with a lower risk of depressive symptoms, particularly among women with nap durations of 5 to 30 minutes, who had the lowest risk of depressive symptoms. Specifically, individuals with nap durations of 5 to 30 minutes had a lower risk of depressive symptoms (HR=0.750, 95% CI 0.637 to 0.883, P<0.001), whereas those with naps longer than 60 minutes did not show a significant reduction in depressive symptom risk (HR=0.934, 95% CI 0.811 to 1.076, P=0.347). Further path analysis showed that there is a total indirect effect between napping and depressive symptoms (β=-0.0219, P<0.05), and there is an overall effect between the two (β=-0.081, P<0.05), indicating that napping could indirectly alleviate depressive symptoms by slowing frailty progression and reducing CRP levels. Subgroup analysis showed that the protective effect of napping on depressive symptoms was more pronounced among women who did not smoke or drink, exercised regularly, and participated in social activities, suggesting that the psychological protective effect of napping depends on an individual's overall health behavior pattern.
Daytime napping exerts a chain mediating effect on depressive symptoms in older women through frailty status and CRP levels. Moderate napping, especially short naps of 5 to 30 minutes, can effectively reduce the risk of depressive symptoms, and this effect may be achieved by improving physical function and alleviating frailty and inflammatory responses.