The purposes of this study were to investigate the effects of gender and marital status on depression among middle-aged and older people in China, and to explore the mediating effect of subjective well-being and the moderating effect of degree of digitization in the relationship between subjective well-being and depression. A total of 15,586 Chinese middle-aged and older people (≥ 45 years old) were included in the study using data from the 2018 China Health and Retirement Longitudinal Survey (CHARLS). T-test, ANOVA, hierarchical regression and Bootstrap methods were adopted to test the mediating role of subjective well-being and the moderating role of degree of digitization. The results showed that middle-aged and older women were more likely to suffer from depression than men, and married middle-aged and older people were less likely to be depressed than those who were separated or divorced, widowed and never married. Subjective well-being partially mediated the relationship between gender and depression, and masked the relationship between marital status and depression, and all five dimensions it contains also played a mediating role. Degree of digitization moderated the effect of subjective well-being on depression. Simple slope tests indicated that the effect of subjective well-being on depression increased as degree of digitization increased. In conclusion, to address the mental health problems of middle-aged and older people brought about by the ageing and digital society, we should start by improving their subjective well-being and promoting their integration into the digital society.

Background: Cognitive function and health-related quality of life (HRQoL) are important issues in diabetes care. According to the China Association for Aging, it is estimated that by 2030, the number of elderly people with dementia in China will reach 22 million. The World Health Organization reports that by 2044, the number of people with diabetes in China is expected to reach 175 million. Methods: Cohort analyses were conducted based on 854 diabetic patients aged ≥45 years from the third (2015) and fourth (2018) survey of the China Health and Retirement Longitudinal Study (CHARLS). Correlation analysis, repeated-measures variance analysis, and cross-lagged panel models were used to measure the difference in digital usage behavior in the established relationship. Results: The results show that the cognitive function of middle-aged and older diabetic patients is positively correlated with HRQoL. HRQoL at T1 could significantly predict cognitive function at T2 (PCS: B = 0.12, p < 0.01; MCS: B = 0.14, p < 0.01). This relationship is more associated with individual performance than digital usage behavior. Conclusions: Unidirectional associations may exist between cognitive function and HRQoL among middle-aged and older Chinese diabetes patients. In the future, doctors and nurses can recognize the lowering of self-perceived HRQoL of middle-aged and older diabetic patients, and thus draw more attention to their cognitive function, in turn strengthening the evaluation, detection, and intervention of their cognitive function.

Background More activity participation is an important means of handling depression and promoting positive aging, but the impact of changes in activity participation on the developmental trajectory of depression has not been fully studied. Objective The purpose of this study is to study the relationship between current activity participation and depression in middle-aged and older people (≥45 years old) and the relationship between activity participation and the developmental trajectory of depression in later life in China. Methods This study used data from the China Health and Retirement Longitudinal Study (CHARLS) across 7 years and included a total of 4818 middle-aged and older people (≥45 years old). Controlling for relevant control variables, the latent growth curve model and the cross-lag model were used to assess the effect of changes in activity participation on the depression trajectory in later life and the main lag relationship between activity participation and depression. Activity participation as well as depression were measured using the self-reported activity and health status based on the CHARLS questionnaire. Results Among the 4818 respondents, the mean values of physical activity participation, social leisure activity participation, and depression ranged from 76.98 (SD 15.16) to 83.95 (SD 5.72), from 7.43 (SD 8.67) to 9.25 (SD 10.16), and from 7.61 (SD 5.72) to 8.82 (SD 6.51), respectively. Our findings revealed that activity participation could be related to depression. Physical activity participation predicted initial depression (β=–0.631, P<.001) and its trajectory (β=0.461, P<.001). However, social leisure activity participation predicted initial depression (β=–0.223, P<.001) but did not predict its trajectory (β=0.067, P=.159). Finally, cross-lag regression analysis further demonstrated the predictive effect of activity participation on depression. Conclusions This study demonstrates the prediction of activity participation for future depression in the Chinese middle-aged and older populations. The data showed that activity participation is significantly associated with changes in depression and future depression among middle-aged and older people in China. The Chinese government should encourage middle-aged and older people to participate in various activities, which can effectively prevent the aggravation of depression and also have a positive significance for positive aging.

Household air pollution (HAP) is suggested to increases people's risk of disability, but mediating mechanisms between HAP and disability remains under-investigated. The aim of this study was to investigate the underlying mechanisms between household air pollution and disability in middle-aged and older adults (i.e., older than 45 years) using a nationally representative prospective cohort. In total, 3754 middle-aged and older adults were selected from the China Health and Retirement Longitudinal Study. Correlation analysis and logistic regression analysis were employed to estimate the association between HAP, pain, depression and disability. Finally, three significant mediation pathways through which HAP directly impacts disability were found: (1) pain (B = 0.09, 95% CI 0.01, 0.02), accounting for 15.25% of the total effect; (2) depression (B = 0.07, 95% CI 0.004, 0.02), accounting for 11.86% of the total effect; (3) pain and depression (B = 0.04, 95% CI 0.003, 0.01), accounting for 6.78% of the total effect. The total mediating effect was 33.89%. This study clarified that HAP can indirectly affect disability through the respective and serial mediating roles of pain and depression. These findings potentially have important implications for national strategies concerning the widespread use of clean fuels by citizens.

Objectives This systematic review aims to evaluate the effects of exercise combined with diet (ECWD), exercise alone, diet alone, and no intervention on body composition and serum biochemical markers in adolescents with obesity to provide reference for solving the metabolic disorders of adolescents caused by obesity. Methods Studies published before January 5, 2021 were retrieved from PubMed, Web of Science, Ovid, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang data, VIP database, and SinoMed. Randomized controlled trials with an age between 10 and 20 years, body mass index (BMI) ≥28 kg/m2 or ≥95th percentiles, no history of endocrine and metabolic diseases, heart disease, hematologic disease, and so on before the trial were included. Results Fifteen of the 50,155 studies met the criteria. Meta-analysis showed that ECWD was more effective in reducing BMI (kg/m2) (−2.45 kg/m2, 95% CI: −3.06; −1.85) and fat thickness of back (−13.77 mm, 95% CI: −15.92; −11.62), abdomen (−11.56 mm, 95% CI: −14.04; −9.09), and upper arm (−14.81 mm, 95% CI: −16.74; −12.89) than other interventions; in reducing body fat (−7.03 kg, 95% CI: −9.77; −4.29) and thigh circumference (−4.05 cm, 95% CI: −5.58; −2.52), ECWD and diet alone were more effective than exercise alone; ECWD and exercise alone were more effective in reducing waist circumference (−6.05 cm, 95% CI: −8.37; −3.72), waist-to-hip ratio (WHR; −0.06, 95% CI: −0.11; −0.01), upper arm circumference (−2.57 cm, 95% CI: −3.70; −1.45), triglycerides (TG; −0.30 mmol/L, 95% CI: −0.45; −0.14), total cholesterol (TC; −0.30 mmol/L, 95% CI: −0.59; −0.01), and low density lipoprotein (LDL; −0.22 mmol/L, 95% CI: −0.40; −0.04) than diet alone. ECWD also had effects on tumor necrosis factor-α (TNF-α), interleukin-6, leptin, and so on. Conclusions ECWD is more effective than exercise alone, diet alone, or no intervention in solving the problems of body shape and metabolic disorder of adolescents with obesity.