Background: Physical frailty is a common characteristic of older people with the ageing process and has been viewed as a major public health issue. The longitudinal association between different social engagement and physical frailty among older people has not been explored adequately in China. Marital status forms a critical context for the link between social engagement and frailty among older people, which might constitute a moderating process. The purpose of the present study is to investigate the longitudinal association between social engagement and the changes in physical frailty among Chinese older adults, and to examine whether the association between social engagement and frailty differs by marital status. Methods: The data use in this study were from the data from the China Health and Retirement Longitudinal Study aged 60+ years from 2011 to 2015. A total of 6575 respondents who participated in at least one follow-up wave were included in the analysis. The relationship between social engagement and changes in frailty over time, and the moderating role of marital status were estimated using individual fixed-effects models. Sensitive analyses were conducted to test the robustness of the results. Results: After adjusting the confounders, participants who interact with friends (Coef: -1.309, P < 0.001), engaging in hobby groups (Coef: -1.189, P < 0.001), engaging in sports groups (Coef: -0.945, P = 0.001), and volunteering (Coef: -1.957, P = 0.001) with a frequency of almost daily had a significantly lower frailty risk than participants who never engaging in those activities. The association between frequent engaging in hobby groups and physical frailty was strongest for unmarried than married older adults (Coef: -1.325, P = 0.031). Conclusions: Frequent social engagement might help to decrease the risk of frailty in the Chinese older population. This finding has important implications for public health policy and encourages the incorporation of a broad range of social engagement into the daily lives of older individuals. Specially, encouraging unmarried older adults to engage in intellectual activities, such as playing chess or Mahjong with others, may be an effective way to reduce physical frailty.

Background: Loneliness and social isolation are global public health challenges. Sensory impairments (SIs) are highly prevalent among older adults but are often ignored as a part of normal aging. Identifying the role of SIs in loneliness and social isolation could provide insight into strategies for improving public health among older adults. Objective: This study aims to analyze the effects of SIs on loneliness and social isolation among older adults in rural and urban China. Methods: This cohort study of 3069 older adults (aged 60+) used data from 4 waves (2011, 2013, 2015, and 2018) of the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative survey of adults aged 45 years or older. SIs include hearing impairment (HI), vision impairment (VI), and dual sensory impairment (DSI). DSI is defined as the co-occurrence of VI and HI. Participants with complete data on hearing, vision, social isolation, and loneliness were included in the analysis. Generalized estimating equation models adjusted for covariates were used to examine the relationships of DSI with loneliness and social isolation among older adults. Results: Older adults in rural areas have higher prevalence of DSI, loneliness, and social isolation than their urban counterparts. In rural areas, participants with VI only (odds ratio [OR] 1.34, 95% CI 1.12-1.62; P=.002), HI only (OR 1.32, 95% CI 1.02-1.71; P=.03), and DSI (OR 1.84, 95% CI 1.56-2.18; P<.001) were more likely to experience loneliness compared with participants without SIs. DSI showed a statistically significant association with loneliness compared with VI only (OR 1.37, 95% CI 1.22-1.54; P<.001) and HI only (OR 1.39, 95% CI 1.13-1.72; P=.002). In urban areas, participants with VI only (OR 2.44, 95% CI 1.57-3.80; P<.001), HI only (OR 2.47, 95% CI 1.41-4.32; P=.002), and DSI (OR 1.88, 95% CI 1.24-2.85; P=.003) were more likely to experience loneliness compared with participants without SIs. DSI was not associated with the increased likelihood of loneliness compared with HI only or VI only. SIs were not associated with social isolation among older adults in urban and rural areas. Until 2018, 86.97% (2669/3069) reported VI, but only 27.11% (832/3069) and 9.45% (290/3069) were treated with glasses and cataract surgery, respectively; besides, 75 individuals received both glasses and cataract surgery treatment. The prevalence of HI was 74.39% (2283/3069) in 2018, but only 0.72% (22/3069) were treated with a hearing aid. Conclusions: SIs are associated with an increased risk of loneliness rather than social isolation. A compounded risk of DSI on loneliness exists in rural areas rather than in urban areas. These findings expand our knowledge about the effects of SIs on loneliness and social isolation in non-Western populations. Interventions targeting HI only and DSI might be particularly effective for mitigating loneliness of older adults in urban and rural areas, respectively. Considering the high prevalence and low treatment rate of SIs, measures should be taken to make treatment more accessible.

Background: Risky sexual behaviors remain significant public health challenges among adolescents. Nearly 90% of adolescents live in low and middle-income countries (LMICs), but few studies have used standardized methodology to monitor the prevalence and trends of sexual behaviors among adolescents in LMICs. Objective: This study aimed to assess the prevalence of sexual behaviors (ever had sexual intercourse, multiple sexual partners, and condom use) among adolescents aged 12 years to 15 years as well as the trends in prevalence between 2003 and 2017. Methods: For this population-based study, we used recent data from the Global School-based Student Health Survey conducted in 69 LMICs from 2003 to 2017 to assess the recent prevalence of sexual behaviors by using complex analysis and a random effects meta-analyses method. Using the chi-square trend test, we also assessed the trends in the prevalence of sexual behaviors in 17 countries that had conducted ≥1 round of surveys from 2003 to 2017. Results: We included 145,277 adolescents aged 12 years to 15 years (64,719/145,277, 44.5% boys) from the 69 LMICs that had conducted ≥1 survey and 80,646 adolescents aged 12 years to 15 years (34,725/80,646, 43.1% boys) from the 17 LMICs that had conducted ≥1 round of surveys. The recent global prevalence of ever had sexual intercourse was 6.9% (95% CI 6.2%-7.6%) and was higher among boys (10.0%, 95% CI 9.1%-11.1%) than girls (4.2%, 95% CI 3.7%-4.7%) and among those aged 14 years to 15 years (8.5%, 95% CI 7.7%-9.3%) than those aged 12 years to 13 years (4%, 95% CI 3.4%-4.7%). Among adolescents who had ever had sex, the recent global prevalence of having multiple sexual partners was 52% (95% CI 50.4%-53.6%) and was higher among boys (58%, 95% CI 56.1%-59.9%) than girls (41.4%, 95% CI 38.9%-43.9%) and among those aged 14 years to 15 years (53.5%, 95% CI 51.6%-55.4%) than those aged 12 years to 13 years (49.7%, 95% CI 45.9%-53.5%). Among adolescents who had ever had sex, the recent global prevalence of condom use was 58.1% (95% CI 56.2%-59.9%) and was higher among girls (59.2%, 95% CI 56.4%-61.9%) than boys (57.7%, 95% CI 55.7%-59.7%) and among those aged 14 years to 15 years (59.9%, 95% CI 58.0%-61.8%) than those aged 12 years to 13 years (51.6%, 95% CI 47.5%-55.7%). Between the earliest and latest surveys, the overall prevalence of ever had sexual intercourse (3.1% decrease) and condom use (2.0% decrease) showed downward trends. The overall prevalence of having multiple sexual partners increased by 2.6%. Conclusions: We provide evidence and important implication for policymakers to develop targeted policy support systems to prevent and reduce risky sexual behaviors among young adolescents in LMICs with a high prevalence of risky sexual behaviors.

Background: Frailty and cognitive impairment are two common geriatric symptoms linking adverse health-related outcomes. However, cognitive frailty, a new definition defined by an international consensus group, has been shown to be a better predictor of increased disability, mortality, and other adverse health outcomes among older people than just frailty or cognitive impairment. This study estimated the prospective association between social support and subsequent cognitive frailty over 1 year follow-up, and whether psychological distress mediated the association. Methods: The data was drawn from a prospective repeated-measures cohort study on a sample of participants aged 60 and over. A total of 2785 older people who participated in both of the baseline and 1-year follow-up survey were included for the analysis. Cognitive frailty was measured by the coexistence of physical frailty and cognitive impairment without dementia. Control variables included sex, age, education, marital status, economic status, smoking status, alcohol drinking status, chronic conditions, and functional disability. Path analyses with logistic function were performed to examine the direct effects of social support (predictors) on subsequent cognitive frailty (outcome) at 1-year follow-up and the mediating role of psychological distress (mediator) in this link. Results: After adjusting for covariates and prior cognitive frailty status, social support was negatively associated with psychological distress (β = − 0.098, 95% CI = − 0.137 to − 0.066, P < 0.001) and was negatively associated with the log-odds of cognitive frailty (β = − 0.040, 95% CI = − 0.064 to − 0.016, P < 0.001). The magnitude of mediation effects from social support to cognitive frailty via psychological distress was a*b = − 0.009, and the ratio of a*b/(a*b + c’) was 24.32%. Conclusions: Lower social support is associated with increased rates of subsequent cognitive frailty over 1-year follow-up, and this link is partially mediated through psychological distress, suggesting that assessing and intervening psychological distress and social support may have important implications for preventing cognitive frailty among older people.

Background: Preliminary evaluations have found that family doctor contract services (FDCSs) have significantly controlled medical expenses, better managed chronic diseases, and increased patient satisfaction and service compliance. In 2016, China proposed the establishment of a family doctor system to carry out contract services, but studies have found the uptake and utilization of these services to be limited. This study aimed to investigate rural residents’ preferences for FDCSs from the perspective of the Chinese public. Methods: A discrete choice experiment (DCE) was performed to elicit the preferences for FDCSs among rural residents in China. Attributes and levels were established based on a literature review and qualitative methods. Five attributes, i.e., cost, medicine availability, the reimbursement rate, family doctor competence, and family doctor attitude, were evaluated using a mixed logit model. Results: A total of 609 residents were included in the main DCE analysis. The respondents valued the high competence (coefficient 2.44, [SE 0.13]) and the good attitude (coefficient 1.42, [SE 0.09]) of family doctors the most. Cost was negatively valued (coefficient − 0.01, [SE 0.01]), as expected. Preference heterogeneity analysis was conducted after adjusting the interaction terms, and we found that rural residents with higher educational attainment prefer a good attitude more than their counterparts with lower educational attainment. The estimated willingness to pay (WTP) for “high” relative to “low” competence was 441.13 RMB/year, and the WTP for a provider with a “good” attitude relative to a “poor” attitude was 255.77 RMB/year. Conclusion: The present study suggests that strengthening and improving the quality of primary health care, including the competence and attitudes of family doctors, should be prioritized to increase the uptake of FDCSs. The contract service package, including the annual cost, the insurance reimbursement rate and individualized services, should be redesigned to be congruent with residents having different health statuses and their stated preferences.

Childhood abnormal weight status is a global public health issue. This study aims to explore the association between maternal education and weight status of school-age children using the data from the China Health Nutrition Survey (CHNS), wave 2011. Body Mass Index (BMI) is calculated based on children’s weight and height and is divided into three levels (normal, underweight, overweight/obesity). Logistic regression is used to assess the relationship of maternal education and children weight status. The prevalence of childhood underweight and overweight/obesity are 5.9% and 21.7%, respectively. Children with high maternal education are found less likely to be underweight (technical college: Odds Ratio (OR) = 0.223, 95% Confidence Interval (CI) = 0.052–0.956, above college: OR = 0.182, 95% CI = 0.041–0.812). Children with maternal education at junior high school are of 2.170 greater odds to be overweight/obese than those with maternal education at junior high school and below (OR = 2.170, 95% CI = 1.398–3.370), and children with maternal education at technical college are of 2.397 greater odds to be overweight/obese than those with lower education level (OR = 2.397, 95% CI = 1.478–3.887), and children with maternal education at above college are of 2.146 greater odds to be overweight/obese than those with lower education level (OR = 2.146, 95% CI = 1.293–3.560). A significant association between maternal education and children’s weight status is found. Targeted interventions for mothers with different education levels should be carried out to effectively manage the children’s weight status.