Objective: To investigate the personal wellbeing index (PWI) among elderly aged 55 and above from the elderly day care centers in Macao, Hong Kong and Guangzhou, and associated factors. Methods: We used convenient sampling to select participants from 16 elderly day care centers in Macao, Hong Kong and Guangzhou. Inclusion criteria were: females aged 55 or above, males 60 or above, the participants who were conscious and clearly understood the questionnaire. Informed consent form was signed by the participants. A total of 324 elderly participated in the study: 90 from Macao, 100 from Hong Kong, and 134 from Guangzhou. Close-end questionnaire was used to collect demographic information and PWI inventory (Cantonese version) was used to assess the PWI scores. Comparison in the PWI scores difference was conducted. Multiple regression method was used to analyze factors associated with PWI. Results: The PWI was 7.3±1.9 (Macao: 7.7±1.9, Hong Kong: 7.2±1.7, Guangzhou: 7.0±1.9) (F=3.32, P=0.037). The multiple regression analysis showed that comparing to those who did exercised 3 times or less, or single/devoiced/separated, or had no education, the elderly who did exercised 4 times or more per week or married/widowed, or received education in primary school or above had higher PWI scores. The beta values (95%CI) were 0.82 (95% CI: 0.31-1.34), 1.03 (95% CI: 0.12-1.94), 0.51 (95% CI: 0.04-0.99) respectively. Conclusion The elderly participants aged 55 or above who went to elderly day care centers in three cities had higher PWI score generally. Marital status, participate in sufficient physical activity and advanced education level were significant related to PWI.

Background Preterm birth-related complications are the leading cause of death in newborns and children under the age of 5 years. Maternal heat exposure has been associated with both sleep status during pregnancy and the increased risk of preterm birth. However, whether sleep status could mediate the association between heat exposure and preterm birth remains unclear. Objective To evaluate the association between maternal heat exposure in early pregnancy and preterm birth, and to further explore potential mediation effect of sleep status on the association between heat exposure and preterm birth. Methods A birth cohort was established in Guangzhou Panyu Maternal Child Health Hospital (Guangzhou Panyu District He Xian Memorial Hospital) from 2017 until now. Pregnant women (with gestational age between 8 and 13 weeks) were included in this study when they presented to the hospital for their first prenatal care visit and signed an informed consent. Then they were followed up until delivery. A total of 3 268 pregnant women were included for the final analysis. Questionnaires were distributed to collect the demographic characteristics, lifestyles, and sleep status of pregnant women. Daily meteorological data during the study period were collected from meteorological monitoring stations in Guangzhou and the average ambient mean temperature of four weeks before the survey was calculated and assigned for each pregnancy. The 75th, 80th, 85th, 90th, and 95th percentiles (P₇₅, P₈₀, P₈₅, P₉₀, and P₉₅) of the average ambient temperature of all pregnant women were used as the thresholds to define heat exposure. Logistic regression was used to evaluate the effects of heat exposure in different definitions on preterm birth and sleep status (sleep duration, night sleep timing, and wake up timing). The mediation effects of sleep status on the relationship between heat exposure and preterm birth were also analyzed. Results Among all the included participants, 165 newborns were preterm births with an incidence rate of 5.0%. Heat exposures with thresholds of P₉₀ and P₉₅ increased the risk of preterm birth, with ORs (95%CIs) of 1.66 (1.04-2.57) and 1.90 (1.03-3.33), respectively (P<0.05). Heat exposures with thresholds of P₇₅, P₈₀, P₈₅, P₉₀, and P₉₅ decreased the sleep duration (<9 h vs. ≥9 h, control group: ≥9 h), and the ORs (95%CIs) were 1.51 (1.25-1.83), 1.44 (1.17-1.77), 1.35 (1.08-1.70), 1.43 (1.09-1.87), and 1.45 (1.00-2.13), respectively. Heat exposures with P₇₅ and P₈₀ thresholds resulted in earlier wake up timing (<8: 00 vs. ≥8: 00, control group: <8: 00), with ORs (95%CIs) of 0.77 (0.63-0.93) and 0.76(0.61-0.93), respectively. No significant association was observed between heat exposure and night sleep timing. The mediation analyses showed that under heat exposure with P₉₀ threshold, a statistically significant mediation effect was observed for sleep duration, and the proportion mediated was 6.07% (95%CI: 0.17%-25.00%) (P<0.05). No significant mediation effect was observed for night sleep timing and wake up timing. Conclusion An elevated risk of preterm birth after heat exposure in early pregnancy may be partly mediated through reducing sleep duration.