[Association between depression and chronic diseases among middle-aged and older Chinese adults].

OBJECTIVE: To examine the association between depressive symptoms and chronic diseases among middle-aged and older Chinese adults within a national investigation. METHODS: Data used in current analysis were obtained from a nationally representative, cross-sectional population-based survey of China health and retirement longitudinal study, which were conducted in 2011 using four-stage probability-proportional-to-size sampling methods. A total of 10 420 participants who were aged 45 years and above from 28 provinces in mainland China were included. Information on demographic characteristics (e.g., age, gender, education level), lifestyle factors (e.g., smoking status and drinking frequency) and chronic diseases (e.g., hypertension, diabetes, and stroke) were collected by well-trained interviewers at the interviewees' homes using a standardized questionnaire. Depressive symptoms were measured using the 10-item version of the center for epidemiological studies depression scale (CESD-10, which was a widely used standard tool in Chinese population, and elevated depressive symptoms were defined by a cut-off ≥10. Multivariate Logistic regression analysis was carried out to assess the association between depressive symptoms and chronic diseases (including hypertension, diabetes, heart disease, dyslipidemia and stroke), adjusting for age, gender, education level, marital status, ethnicity, place of residence, bady mass index (BMI) and other potential confounding factors. RESULTS: Among the 10 420 participants, the mean age was (59.2±9.4) years, and 48.2% of them were men. There were 3 900 (37.4%) participants who had a depression rating score of 10 or greater, indicative of elevated depressive symptoms. The results of multivariate Logistic regression analysis demonstrated that diabetes (OR=1.230, 95%CI: 1.080-1.401), hypertension (OR=1.335, 95%CI: 1.205-1.480), heart disease (OR=1.953, 95%CI: 1.711-2.229), and stroke (OR=2.269, 95%CI: 1.704-3.020) were significantly associated with depressive symptoms (P < 0.05), after full adjustment of age, gender, education level, marital status, ethnicity, residency and other potential confounders. While no significant relationship was found between dyslipidemia and depressive symptoms (P>0.05). The prevalence of elevated depressive symptoms increased parallel with the number of chronic diseases (Ptrend < 0.001). CONCLUSION: Depressive symptoms were significantly associated with chronic diseases (including diabetes, hypertension, heart disease, and stroke), which suggests that psychological factors, such as depressive symptoms should be taken into consideration in the prevention and control of chronic diseases.

Local body cooling to improve sleep quality and thermal comfort in a hot environment.

The effects of local body cooling on thermal comfort and sleep quality in a hot environment were investigated in an experiment with 16 male subjects. Sleep quality was evaluated subjectively, using questionnaires completed in the morning, and objectively, by analysis of electroencephalogram (EEG) signals that were continuously monitored during the sleeping period. Compared with no cooling, the largest improvement in thermal comfort and sleep quality was observed when the back and head (neck) were both cooled at a room temperature of 32°C. Back cooling alone also improved thermal comfort and sleep quality, although the effects were less than when cooling both back and head (neck). Mean sleep efficiency was improved from 84.6% in the no cooling condition to 95.3% and 92.8%, respectively, in these conditions, indicating good sleep quality. Head (neck) cooling alone slightly improved thermal comfort and subjective sleep quality and increased Stage N3 sleep, but did not otherwise improve sleep quality. The results show that local cooling applied to large body sections (back and head) could effectively maintain good sleep and improve thermal comfort in a hot environment.

Field study of a thermal environment and adaptive model in Shanghai.

A long-term field investigation was carried out in naturally ventilated residential buildings in Shanghai from April 2003 to November 2004. A total of 1,768 returned questionnaires were collected in the study. This study deals with the thermal sensation of occupants in naturally ventilated buildings and the change in thermal neutral temperature with season. The range of accepted temperature in naturally ventilated buildings is between 14.7 degrees C T(op) and 29.8 degrees C T(op). The results also report the findings of the adaptive comfort model in Shanghai that determines the adaptive relationship of neutral temperature with outdoor air temperature. A long-term field study was carried out in residential buildings in Shanghai to find the relationship between thermal sensation, indoor neutral temperature and outdoor temperature. This paper presents findings of thermal comfort and discusses the more sustainable standard for the indoor climate of residential buildings in Shanghai.