[Characteristics of daytime napping and its correlation with chronic diseases in Chinese adults].

Objective: To describe the prevalence of daytime nap habit in participants of the China Kadoorie Biobank (CKB) study, across 10 study regions and explore its correlation with prevalence of major chronic diseases. Methods: Participants with a self-reported pre-diagnosis of any cancer at baseline survey were excluded. Logistic regression models were used to analyze the differences in study regions and age distribution of the prevalence daytime nap habit, and its correlation with the prevalence of diabetes, hypertension, coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), and chronic liver diseases. Results: Among 510 145 participants, 39.9% had daytime nap habit in summer and 20.8% had daytime nap habit all the year round. Urban-rural differences were observed in the prevalence of summer nap habit and perennial nap habit. Daytime nap in summer was common in rural areas and Suzhou, with prevalence ranged from 32.9% to 73.3%. Haikou and Liuzhou had higher prevalence of perennial nap (60.4% and 63.3%). The proportion of people with daytime nap habit all the year round increased with age (P for trend <0.001), the proportion was highest in those aged 70- years (31.9%). Daytime nap habit in summer was positively correlated with the prevalence of diabetes, hypertension, CHD and chronic liver disease with OR of 1.10 (95%CI: 1.07-1.14), 1.03 (95%CI:1.02-1.05), 1.07 (95%CI: 1.02-1.12) and 1.07 (95%CI:1.00-1.14), respectively. Daytime nap habit all the year round was positively correlated with the prevalence of diabetes, hypertension, CHD, stroke, COPD and chronic liver disease with OR of 1.33 (95%CI: 1.29-1.37), 1.11 (95%CI: 1.09-1.13), 1.39 (95%CI: 1.33-1.45), 1.33 (95%CI: 1.26-1.41), 1.12 (95%CI: 1.08-1.16) and 1.27 (95%CI:1.18-1.37) respectively. Conclusion: There were regional and age differences in prevalence of daytime nap habit among CKB participants. Daytime nap habit, especially daytime nap habit all the year round, was positively correlated with the prevalence of major chronic diseases.

[The correlation of physical activity and sedentary leisure time with low muscle mass, strength, and quality in Chinese adults].

Objective: To explore the relationship of physical activity and sedentary leisure time with muscle mass, strength, and quality in Chinese adults. Methods: Based on the second resurvey of China Kadoorie Biobank (CKB) in 2013-2014, logistic regression models were used to analyze the correlation of physical activity and sedentary leisure time with low muscle mass, grip strength, and muscle quality. Results: A total of 24 245 participants were included in the analysis. The average daily physical activity level was (18.3±13.8) MET-h/d, and the sedentary leisure time was (4.4±1.9) hours. We took the lowest physical activity quartile as the reference and found that the participants' physical activity was negatively correlated to low muscle mass, strength, and quality. The ORs (95%CIs) of low appendicular skeletal muscle mass index (ASMI), low total skeletal muscle mass index (TSMI), low grip strength and low arm muscle quality (AMQ) were 0.68 (0.60-0.77), 0.66 (0.58-0.75), 0.82 (0.72-0.94) and 0.84 (0.74-0.95), respectively. The subtypes of physical activity, including those related to work, transportation, housework, and leisure, also showed negative correlations with low muscle mass, strength, and quality to varying degrees. Compared with participants with the shortest sedentary leisure time, those who had the longest were more likely to have low TSMI (OR=1.13, 95%CI: 0.99-1.30). Conclusions: Physical activity was negatively correlated with a lower risk of low muscle mass and strength, while longer sedentary leisure time positively correlated with low muscle mass.

[Spicy food consumption and risk of lip, oral cavity and pharynx cancers: a prospective cohort study of Chinese adults].

Objective: To explore the association of spicy food consumption and risk of lip, oral cavity, and pharynx cancers (LOCPs) in Chinese adults. Methods: Based on the baseline survey and long-term follow-up of the China Kadoorie Biobank (CKB) study, Cox proportional hazard regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) for associations between spicy food consumption and LOCPs incidence. Results: Of the 510 145 participants included at baseline, 30.1% reported daily spicy food consumption. During a mean follow-up of 10.8 (2.0) years, we documented 767 LOCPs cases. Multivariate adjusted analyses showed that the risk of LOCPs incidence decreased with the frequency of spicy food intake (trend P=0.003), with HR of 0.69 (95%CI:0.54-0.88) for daily spicy food consumers, compared with never or occasional consumers. Participants who preferred moderate pungency degrees had the lowest risk of LOCPs, with a 33%[0.67(95%CI:0.52-0.87)] reduced risk compared to those who consumed spicy food less than once per week. The later the starting age, the lower the risk (trend P=0.004). Those who started eating spicy food after 18 years old had the lowest risk of LOCPs incidence, with adjusted HR (95%CI) of 0.70(0.54-0.92). Conclusions: Spicy food intake might be associated with a decreased risk of LOCPs incidence. Such association was independent of healthy lifestyles. Advocating moderate-pungency spicy food consumption and healthy lifestyles might help prevent LOCPs.

[The correlation of sleep duration and insomnia with low muscle mass, strength and quality in Chinese adults].

Objective: To explore the relationship of sleep duration and insomnia with muscle mass, strength, and quality in Chinese adults. Methods: Based on the second resurvey of China Kadoorie Biobank (CKB) in 2013-2014, logistic regression models were used to analyze the correlation of sleep duration, insomnia, and its duration with low muscle mass, handgrip strength, and muscle quality. Results: The average sleep duration of the study population was (7.4±1.5) hours. Morbidities of short sleep duration (<6 hours), long sleep duration (≥9 hours), and insomnia were 9.3%,17.4%,and 29.9%,respectively. Compared with those who slept for 7- hours, those who slept for ≥9 hours were more likely to have low muscle mass, low handgrip strength,and low arm muscle quality (AMQ), and the OR (95%CI) of low appendicular skeletal muscle mass index (ASMI), low total skeletal muscle mass index (TSMI), low grip strength and low AMQ were 1.32 (1.18-1.48),1.26 (1.13-1.41), 1.33 (1.18-1.49) and 1.16 (1.03-1.30), respectively. Compared with participants without insomnia, insomnia patients were more likely to have low muscle mass,and the longer the duration of insomnia,the higher the risk (P for trend <0.001). Participants who reported <6 hours sleep duration and insomnia had a higher proportion of low ASMI and low TSMI,compared with those who slept for 7- hours and without insomnia, the OR (95%CI) were 1.26 (1.08-1.47) and 1.25 (1.07-1.46), respectively. Conclusions: Participants who reported ≥9 hours sleep duration were more likely to have low muscle mass,low handgrip strength,and low AMQ. Participants with insomnia had lower muscle mass, and the longer the duration of insomnia, the higher the proportion of low ASMI and low TSMI.

[Correlation between chronic diseases and low muscle mass, strength and quality in adults in China].

Objective: To explore the correlation between chronic diseases and muscle mass, strength and quality in adults in China. Methods: Based on the second resurvey of China Kadoorie Biobank (CKB) in 2013-2014, logistic regression models were used to analyze the correlation of different types, number and duration of chronic diseases with low muscle mass, handgrip strength and muscle quality. Results: The prevalence rate of diabetes, coronary heart disease (CHD), stroke and chronic obstructive pulmonary disease (COPD) were 9.6%, 5.8%, 3.2% and 26.8%, respectively, and 38.8% of the participants had at least one disease, and they were more likely to have low handgrip strength and low arm muscle quality (AMQ), and the longer the chronic diseases duration, the higher the risk. The ORs (95%CIs) for low handgrip strength and low AMQ in patients with 1 chronic disease for more than 10 years was 1.64 (1.42-1.90) and 1.83 (1.60-2.10), respectively. The ORs (95%CIs) for low handgrip strength were 1.26 (1.17-1.37), 1.42 (1.23-1.64) and 2.27 (1.55-3.32) and the ORs (95%CIs) for low AMQ were 1.28 (1.18-1.38), 1.67 (1.46-1.92) and 2.41(1.69-3.45), respectively, in patients with 1, 2, ≥3 chronic diseases, the correlation showed a linear trend (P for trend <0.001). Diabetes, CHD and stroke were positively correlated with low handgrip strength and low AMQ. Compared with participants without COPD, COPD patients were more likely to have low appendicular skeletal muscle mass index (ASMI), low total skeletal muscle mass index (TSMI) and low handgrip strength, and the risk was positively correlated with disease duration. Conclusions: Patients with chronic diseases were more likely to have lower muscle strength and muscle quality, especially the patients with multi diseases and longer disease duration. The proportion of low handgrip strength and low AMQ was higher in patients who reported multi-prevalence and longer duration of chronic diseases.

[The correlation of dietary patterns with low muscle mass, strength and quality in adults from 10 regions of China].

Objective: To evaluate the correlation of dietary patterns with low muscle mass, strength and quality in Chinese adults. Methods: Based on the second resurvey of China Kadoorie Biobank, factor analysis was conducted to derive dietary patterns from 20 food groups. Low muscle mass, strength, and quality were defined as the sex-specific lowest quintile of appendicular skeletal muscle mass index (ASMI), total skeletal muscle mass index (TSMI), handgrip strength and arm muscle quality (AMQ) according to Asian Working Group for Sarcopenia recommendations. Logistic regression models were used to evaluate the correlation of dietary patterns with low muscle mass, strength, and quality. Results: Two major dietary patterns were extracted. The balanced dietary pattern was characterized by the intake of a variety of foods, whereas the rice-meat dietary pattern was characterized by high intakes of rice, meat, poultry and fish. Individuals who had the highest quintile score of the balanced dietary pattern were less likely to have low TSMI, handgrip strength or AMQ(OR=0.83, 95%CI: 0.74-0.95 for low TSMI; OR=0.64, 95%CI: 0.56-0.74 for low handgrip strength; OR=0.82, 95%CI: 0.72-0.93 for low AMQ; for trend P<0.05). And those who scored higher on the rice-meat dietary pattern had lower risk of low muscle mass and strength (OR=0.67, 95%CI: 0.55-0.82 for low ASMI; OR=0.69, 95%CI: 0.56-0.85 for low TSMI; OR=0.74, 95%CI: 0.60-0.91 for low handgrip strength; for trend P<0.05). Conclusion: Individuals followed the balanced dietary pattern, as well as those who followed the rice-meat dietary pattern, had better levels of skeletal muscle mass, strength and quality.