Secular Trends in Sleep Conditions in Chinese Elderly Individuals: A National Population-Based Study.

Purpose: As one of the most rapidly aging countries in the world, the elderly population is expected to reach over 400 million in China by 2032. Many studies have suggested a positive association between sleep duration and adverse health events among elderly individuals. This study aimed to investigate the sleep conditions of Chinese elderly individuals between 2005 and 2018. Patients and methods: Data for 53,013 elderly individuals were taken from five cycles of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) during 2005-2018. Sex- and age-specific means and 95% confidence intervals (95% CIs) were used to estimate sleep duration trends. Changes in sleep patterns were explored during this period. The prevalence of short and long sleep durations was assessed and age-standardized by the 2010 census. Finally, self-reported sleep quality was used to determine sleep conditions from another perspective among elderly individuals. Results: The mean sleep duration decreased from 7.87 (95% CI: 7.83-7.91) to 7.29 (95% CI: 7.25-7.33) hours between 2005 and 2018. Changes in sleep duration patterns were found during the study period. The proportion of the elderly population who slept ≤6 hours increased and that of those who slept ≥9 hours decreased noticeably over the past 13 years. The age-standardized prevalence of short sleep duration increased from 32.7% (95% CI: 32.7-32.9%) to 38.4% (95% CI: 38.3-38.5%). A significant decrease was observed in the prevalence of long sleep duration. Conclusion: Sleep conditions are gradually shifting toward a shorter sleep duration and poorer sleep quality among Chinese elderly individuals.

The Impact of Hypertension Definition Based on Two-visit Strategy on Estimate of Hypertension Burden: Results From the China Health and Nutrition Survey 1989-2011.

BACKGROUND: The diagnosis of hypertension should be based on the mean of two or more properly measured BP readings on each of two visits for clinical practice, but a one-visit strategy was applied in most epidemiological surveys. The impact of hypertension definition based on two visits on estimates of hypertension burden is unknown. This study aims to assess the impact of hypertension diagnosis based on a two-visit strategy for estimating hypertension burden in China. METHODS: The one-visit and two-visit strategies were applied to investigate the incidence of hypertension in a cohort study based on the China Health and Nutrition Survey (CHNS) 1989-2011. Additionally the prevalence of hypertension was investigated in a cross-sectional study based on the CHNS 2006-2009/2011 and the hypertension burden in China was estimated with data from the 2012-2015 China hypertension survey. RESULTS: Overall, the age-adjusted incidence of hypertension based on the two-visit strategy (1.82%; 95% confidence interval [CI], 1.74-1.90%) was 62.1% lower than estimation based on the one-visit strategy (4.80%; 95% CI, 4.68-4.93%). Similar results were found in the prevalence of hypertension (one-visit: 18.13% [95% CI, 17.34-18.92%]; two-visit: 9.47% [95% CI, 8.87-10.07%]). When the two-visit strategy was applied to the 2012-2015 China hypertension survey, the hypertension burden was predicted to be overestimated by 25.5-47.8% (based on JNC 7) and 23.5-48.2% (based on the 2017 ACC/AHA). CONCLUSION: The hypertension burden would decrease from 244.5 million persons to 127.5-182.3 million persons in China if the two-visit strategy was applied.

Trends in age of smoking initiation among the Chinese population born between 1950 and 1997.

OBJECTIVES: Smoking prevalence has significantly increased among Chinese adolescences in the past decades. The aim of our study is to investigate the trends and changing patterns in age of smoking initiation among the Chinese population. STUDY DESIGN: Pooled data from the 2006-2015 China Health and Nutrition Survey was used for analysis. A total of 10,032 adults aged ≥18 years who were born between 1950 and 1997 were separated into five birth cohorts (1950-1959, 1960-1969, 1970-1979, 1980-1989 and 1990-1997). METHODS: Age-specific (10-24 years) smoking initiation rates were calculated by gender, educational level and urbanisation. The multiple logistic models were used for estimates of changes in smoking initiation age. RESULTS: The mean age of smoking initiation decreased substantially from 22.0 years (95% confidence interval [CI]: 21.2-22.7) to 17.5 years (95% CI: 16.2-19.1) over five generations. A large decrease was seen in the initiation age group of 15-24 years in the 1980s cohort (15-19 years: odds ratio [OR] = 0.57; 95% CI: 0.19-0.97; 20-24 years: OR = 0.45; 95% CI: 0.18-0.82); a significant decrease was also found in the 1990s cohort (15-19 years: OR = 0.47; 95% CI: 0.11-0.94; 20-24 years old: OR = 0.34; 95% CI: 0.14-0.85). The peak age of smoking initiation changed from 20 years old to 18 years old over the five generations. CONCLUSIONS: The age of smoking initiation has decreased rapidly in the Chinese population in the past decades. Chinese adolescents are becoming the main target group for the tobacco marketing industry, and national legislations are urgently required.

Associations of fat and carbohydrate intake with becoming overweight and obese: an 11-year longitudinal cohort study.

The effects of macronutrient intake on obesity are controversial. This research aims to investigate the associations between macronutrient intake and new-onset overweight/obesity. The relationship between the consumption of carbohydrate and total fat and obesity was assessed by the multivariable Cox model in this 11-year cohort, which included 6612 adults (3291 men and 3321 women) who were free of overweight and obesity at baseline. The dietary intake was recorded using a 24-h recall method for three consecutive days. Moreover, substitution models were developed to distinguish the effects of macronutrient composition alteration from energy intake modification. During 7·5 person years (interquartile range 4·3, 10·8) of follow-up, 1807 participants became overweight or obese. After adjusting for risk factors, the hazard ratio (HR) of overweight/obesity in extreme quintiles of fat was 1·48 (quintile 5 v. quintile 1, 95 % CI 1·16, 1·89; Ptrend = 0·02) in women. Additionally, replacing 5 % of energy from carbohydrate with equivalent energy from fat was associated with an estimated 4·3 % (HR 1·043, 95 % CI 1·007, 1·081) increase in overweight/obesity in women. Moreover, dietary carbohydrate was inversely associated with overweight/obesity (quintile 5 v. quintile 1, HR 0·70, 95 % CI 0·55, 0·89; Ptrend = 0·02) in women. Total fat was related to a higher risk of overweight/obesity, whereas high carbohydrate intake was related to a lower risk of overweight/obesity in women, which was not observed in men.

Plain Water Intake and Association With the Risk of Overweight in the Chinese Adult Population: China Health and Nutrition Survey 2006-2011.

BACKGROUND: The prevalence of overweight is increasing dramatically worldwide. The aim of our study was to investigate the association of plain water intake (PWI) with the risk of new-onset overweight risk among Chinese adults. METHODS: A total of 3,200 adults aged 18-65 who were free of overweight at baseline were enrolled from China Health and Nutrition Survey (CHNS) cohort study in 2006-2011. The risk of new-onset overweight with different amounts of PWI per day was analyzed in this 5-year cohort. A multiple logistic regression model was used to assess the association of PWI and the risk of new-onset overweight and adjust for potential confounders. Moreover, dose-response models were developed to estimate the linear relationship. RESULTS: During 5 years of follow-up, 1,018 incident cases were identified. Our analysis indicated an inverse association of more than 4 cups of PWI per day and the risk of new-onset overweight among normal weight individuals. Compared with participants who drank 2 to 3 cups PWI, the adjusted odds ratios (OR) of overweight were 0.741 (95% confidence interval [CI], 0.599-0.916) in participants who drank 4 to 5 cups PWI, and 0.547 (95% CI, 0.435-0.687) in participants who drank more than 6 cups PWI. The dose-response analysis showed that every cup of PWI was associated with a 6.5% and 8.4% decrease in the risk of new-onset overweight among men and women, respectively. The interactions of PWI and covariates on the risk of overweight were not found. CONCLUSION: Drinking more than 4 cups (≈1 liter) per day of plain water is associated with decrease in the risk of new-onset overweight among normal-weight individuals.